This study investigated whether rhesus macaques' friendships at age one predicted later plasma concentrations of oxytocin and vasopressin at two time points. The researchers measured friendship types like proximity, play, and reciprocal friendships in 54 juvenile rhesus macaques. They then drew blood samples and measured oxytocin and vasopressin levels. Their results showed that females' reciprocal and play friendships at age one predicted later oxytocin levels. Friendship also predicted vasopressin levels in males. Early involvement in friendships can influence the neuroendocrine systems related to social bonding later in development.
This study examined factors that predict the longitudinal stability of friendships in juvenile rhesus monkeys from age 1 to age 2. The researchers investigated whether individual characteristics (sex, dominance rank, family size, temperament assessed at 3-4 months) and relationship characteristics (kinship, reciprocity, complexity, similarity in sex, rank and temperament) predicted which friendships persisted over time. They found that males maintained more friendships than females from age 1 to 2. Relationships were more likely to be stable if individuals were similar in temperament, were kin, or the same sex. Reciprocated friendships were also more likely to persist than unidirectional relationships. The findings suggest factors influencing friendship maintenance in rhes
This study examined the mediating role of delinquent peer association and the moderating role of parenting practices on the relationship between callous-unemotional (CU) traits and self-reported offending in a sample of 1,216 male juvenile offenders. The findings suggested that the effect of CU traits on offending was partially mediated by delinquent peer association. Additionally, it was found that when both parental warmth and supervision were high, the indirect effect of CU traits on offending through delinquent peers was no longer significant. The results highlight the importance of parenting, particularly both warmth and monitoring, in reducing the influence of delinquent peers on offending for youth with high CU traits.
The document discusses the impact of stigma on family members of individuals with mental illness or drug dependence. It finds that:
1) Family members report experiencing blame, shame, and feeling socially contaminated due to their relation's condition. However, no national survey had assessed how the general public actually views these family members.
2) The study finds that family stigma related to drug dependence is viewed more harshly than other health conditions, with family members being blamed for both the onset and worsening of the relative's disorder and likely to face social shunning.
3) In contrast, family stigma related to mental illnesses like schizophrenia is not highly endorsed by the public according to the survey results.
This study compared behavioral and socio-emotional functioning in children with selective mutism (SM), mixed anxiety disorders (MA), and typically developing controls based on parent, teacher, and child reports. Children with SM were rated lower than controls on social skills but did not differ significantly from those with MA. However, children with SM were rated higher than both other groups on social anxiety. The findings suggest conceptualizing SM as an anxiety disorder characterized primarily by deficits in social functioning and social anxiety, supporting a more specific classification in diagnostic manuals. The results also indicate social skills training could benefit children with anxiety disorders or SM.
Kathleen Jones wrote a literature review on the effects of parental alcoholism on children. The review examined research showing that children with antisocial or depressed alcoholic parents are at greater risk for externalizing symptoms. Parental alcoholism was also linked to increased risk of psychopathology in children, including conduct disorder and depression. However, one study found that only a minority of children of alcoholics develop alcohol problems themselves. Factors like family support and positive influences can help mitigate risks to children in alcoholic families. The review identified areas for further research on identifying the most impactful risk factors and how supportive influences may help children raised in negative environments.
The document summarizes research on the implications of child abuse. It describes 10 studies that find child abuse victims often experience mental health issues like PTSD, depression, anxiety and substance abuse. They also face social and behavioral problems including aggression, low self-esteem and feelings of helplessness. The conclusion states that child abuse dramatically affects victims' development and mental well-being for life.
Dissecting the Stigma- A Relational Analysis of the Triad Between Mother-in-L...Jessica Fletcher
This document summarizes a scholarly research paper on the relationship between mothers-in-law and daughters-in-law. It begins by outlining the existing stigma around negative mother-in-law relationships portrayed in popular culture. It then reviews previous limited scholarly research on the topic, which primarily viewed the relationship negatively from the daughter-in-law's perspective. The document discusses how more recent research examines disclosure and its impact on marital satisfaction. It concludes by introducing the theoretical frameworks of the Triangular Theory of Communication and Uncertainty Reduction Theory that are used in the full research paper to analyze interviews and better understand the complex mother-in-law/daughter-in-law dynamic.
This study examined factors that predict the longitudinal stability of friendships in juvenile rhesus monkeys from age 1 to age 2. The researchers investigated whether individual characteristics (sex, dominance rank, family size, temperament assessed at 3-4 months) and relationship characteristics (kinship, reciprocity, complexity, similarity in sex, rank and temperament) predicted which friendships persisted over time. They found that males maintained more friendships than females from age 1 to 2. Relationships were more likely to be stable if individuals were similar in temperament, were kin, or the same sex. Reciprocated friendships were also more likely to persist than unidirectional relationships. The findings suggest factors influencing friendship maintenance in rhes
This study examined the mediating role of delinquent peer association and the moderating role of parenting practices on the relationship between callous-unemotional (CU) traits and self-reported offending in a sample of 1,216 male juvenile offenders. The findings suggested that the effect of CU traits on offending was partially mediated by delinquent peer association. Additionally, it was found that when both parental warmth and supervision were high, the indirect effect of CU traits on offending through delinquent peers was no longer significant. The results highlight the importance of parenting, particularly both warmth and monitoring, in reducing the influence of delinquent peers on offending for youth with high CU traits.
The document discusses the impact of stigma on family members of individuals with mental illness or drug dependence. It finds that:
1) Family members report experiencing blame, shame, and feeling socially contaminated due to their relation's condition. However, no national survey had assessed how the general public actually views these family members.
2) The study finds that family stigma related to drug dependence is viewed more harshly than other health conditions, with family members being blamed for both the onset and worsening of the relative's disorder and likely to face social shunning.
3) In contrast, family stigma related to mental illnesses like schizophrenia is not highly endorsed by the public according to the survey results.
This study compared behavioral and socio-emotional functioning in children with selective mutism (SM), mixed anxiety disorders (MA), and typically developing controls based on parent, teacher, and child reports. Children with SM were rated lower than controls on social skills but did not differ significantly from those with MA. However, children with SM were rated higher than both other groups on social anxiety. The findings suggest conceptualizing SM as an anxiety disorder characterized primarily by deficits in social functioning and social anxiety, supporting a more specific classification in diagnostic manuals. The results also indicate social skills training could benefit children with anxiety disorders or SM.
Kathleen Jones wrote a literature review on the effects of parental alcoholism on children. The review examined research showing that children with antisocial or depressed alcoholic parents are at greater risk for externalizing symptoms. Parental alcoholism was also linked to increased risk of psychopathology in children, including conduct disorder and depression. However, one study found that only a minority of children of alcoholics develop alcohol problems themselves. Factors like family support and positive influences can help mitigate risks to children in alcoholic families. The review identified areas for further research on identifying the most impactful risk factors and how supportive influences may help children raised in negative environments.
The document summarizes research on the implications of child abuse. It describes 10 studies that find child abuse victims often experience mental health issues like PTSD, depression, anxiety and substance abuse. They also face social and behavioral problems including aggression, low self-esteem and feelings of helplessness. The conclusion states that child abuse dramatically affects victims' development and mental well-being for life.
Dissecting the Stigma- A Relational Analysis of the Triad Between Mother-in-L...Jessica Fletcher
This document summarizes a scholarly research paper on the relationship between mothers-in-law and daughters-in-law. It begins by outlining the existing stigma around negative mother-in-law relationships portrayed in popular culture. It then reviews previous limited scholarly research on the topic, which primarily viewed the relationship negatively from the daughter-in-law's perspective. The document discusses how more recent research examines disclosure and its impact on marital satisfaction. It concludes by introducing the theoretical frameworks of the Triangular Theory of Communication and Uncertainty Reduction Theory that are used in the full research paper to analyze interviews and better understand the complex mother-in-law/daughter-in-law dynamic.
This document summarizes research on the relationship between college-aged youngest siblings and their older siblings. It reviewed literature showing that birth order impacts how siblings interact and the roles they take on. Research found that youngest siblings often feel closer to their mothers than other siblings and value support from their older siblings. The purpose of the study was to understand how these relationships change as siblings age by interviewing college students about their relationships with older siblings.
This document summarizes a research article that examines the prevalence and outcomes of sibling violence. Some key findings:
1) The study uses survey data from over 8,000 secondary school students to estimate rates of sibling abuse and examine its relationship to substance use, delinquency, and aggression.
2) Results suggest sibling violence occurs more frequently than other forms of child abuse. Sibling violence is significantly associated with substance use, delinquency, and aggression even after controlling for other family violence.
3) The study tests feminist theory and social learning theory to help explain why sibling violence occurs. Younger siblings and females are hypothesized to be more likely victims due to power imbalances, and children may learn abusive behaviors
International Journal of Humanities and Social Science Invention (IJHSSI)inventionjournals
International Journal of Humanities and Social Science Invention (IJHSSI) is an international journal intended for professionals and researchers in all fields of Humanities and Social Science. IJHSSI publishes research articles and reviews within the whole field Humanities and Social Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
The study examined how peer networks of female college freshmen related to their romantic involvement. It found that freshmen who were not dating had significantly more female friends and friends living on campus than those who were in a relationship. This suggests that non-dating freshmen felt more comfortable with close social support networks of other females and those nearby. However, the study found few other significant differences and its hypothesis that dating freshmen would have larger, more gender diverse networks was not supported. Limitations included condensed data that ignored cultural and age differences.
The document discusses several studies that examined the relationship between corporal punishment and aggressive behavior in children. The Hicks-Pass study found that children who were spanked had an increase in aggressive behavior towards others and themselves. The Straus and Mouradian study indicated that the more a child was subjected to corporal punishment, the more they developed antisocial behaviors. Another study found that children from homes where neither parent used physical punishment were the least aggressive. While many factors are involved, the studies generally found links between corporal punishment and increased aggression in children.
Violence prevention programs an exploratory study of the chojas18
This document summarizes a study that examined characteristics of youth who participated in a court diversion program for family violence offenses to determine what characteristics prevented completion. The study found that delinquency characteristics like prior violent arrests and school truancy significantly impacted completion rates. Specifically, youth with these risk factors were less likely to successfully complete the program. The findings suggest a more tailored intervention approach is needed for high-risk, multi-problem youth to address recidivism.
The relationship between types ofchildhood victimisation andojas18
This study examined the relationship between different types of childhood victimization (such as physical abuse, neglect, witnessing violence) and criminal behavior in young adulthood. The researchers analyzed data on over 2,000 young Swedish adults who reported experiencing at least one form of childhood victimization. They found that experiences of physical assault, neglect, and witnessing violence as a child were significantly associated with criminal behavior in young adulthood, even after accounting for gender, substance use, and psychopathy. However, experiences of property crimes, verbal abuse, or sexual abuse were not significantly linked to later criminal behavior. This suggests that childhood experiences involving direct violence or witnessing violence carry the greatest risk for criminal behavior in adulthood.
1. The study examined the relationship between social stressors (low parental warmth, peer victimization) experienced in early adolescence and later neural response to rewards and depressive symptoms.
2. Low parental warmth was associated with increased neural response to potential rewards in the medial prefrontal cortex, striatum, and amygdala. Peer victimization was associated with decreased response in the medial prefrontal cortex.
3. Concurrent depressive symptoms at age 16 were associated with increased reward anticipation response in medial prefrontal cortex and striatal regions. Response in these regions mediated the association between early social stressors and later depressive symptoms.
This study examined trajectories of callous-unemotional (CU) traits in a sample of 1,170 male adolescent offenders to predict later violence and substance use. It identified three trajectories of CU traits (low, moderate, high) and found that membership in the high CU trajectory, particularly combined with elevated early conduct problems, predicted higher levels of violence and substance use over time. It also found that the effects of high CU trajectory combined with elevated conduct problems were stronger for those with higher executive control. This highlights how identifying subgroups based on CU trajectories can improve understanding of developmental pathways leading to severe antisocial behavior.
Children exposed to domestic violence can experience psychological effects like anxiety disorders, PTSD, loss of interest in school, substance abuse, and delinquency. They may also have difficulty forming healthy relationships and exhibit self-blame. Witnessing domestic violence can cause increased sensitivity to anger as well as sadness, fear, and stress responses. Exposure to violence and trauma can neurologically impact brain development and potentially lead to the development of abusive personalities. Some states are now considering child exposure to domestic violence a separate criminal charge. Further research is needed using broader definitions of violence and examining health and medical consequences.
Parental Low Self-Control, Family Environments, and Juvenile DelinquencyGeorge Connolly
This study examines the relationship between parental low self-control, family environments, and officially recorded juvenile delinquency. The study hypothesizes that parental low self-control will be associated with poorer family environments (more conflict, less cohesion) and less effective parenting, and will also be associated with greater juvenile delinquency. It further hypothesizes that the effect of parental low self-control on delinquency will be mediated by family environment factors. The study uses survey data from parents of 101 juveniles involved in the juvenile justice system, along with official records of the juveniles' delinquency charges, to test these hypotheses.
Domestic violence psychologically affects victims and families in several ways. It can cause health issues for victims like depression, substance abuse, and chronic illness. Witnessing domestic violence can negatively impact children's development and behavior, lowering IQs and increasing aggression and emotional problems. Exposure to domestic violence has also been linked to intergenerational cycles of abuse, with children of abuse being more likely to become future victims or abusers themselves. Treatment for abusers and support for victims is important to help break these harmful cycles.
This study compared autism and internalizing symptoms in girls and boys with autism spectrum disorders (ASD) between ages 8-18, as well as typically developing girls and boys. It found that girls with ASD showed similar levels of autism symptoms as boys with ASD, and higher levels of internalizing symptoms like depression compared to boys with ASD and typically developing girls during adolescence. The study suggests that girls with ASD resemble boys with ASD in terms of autism traits, but may be at increased risk for conditions like depression as teenagers due to both their ASD and female sex.
Association Between Relationship Quality and Childhood Trauma in Emerging Ad...John Mattscheck, M.A.
This study examined the relationship between childhood trauma and relationship quality in emerging adults. Researchers surveyed 1,904 college students about their trauma history and relationship beliefs, skills, and quality. Results showed that experiencing more childhood trauma was associated with lower quality relationships with parents and grandparents, but not with siblings or friends. There was no significant relationship found between trauma and students' relationship beliefs or interpersonal skills. The researchers hypothesized that resilience and support from non-family relationships may help explain why trauma did not negatively impact all areas of relationships.
In this paper, I researched how aspects of personality can influence behavior; the specific example here is infidelity. I synthesized the data of multiple experiences to create a personality profile of a person who is more likely to cheat on a romantic partner than the "average" person.
This study examined the relationship between autism symptoms, victimization by peers, and aggression in youth with Autism Spectrum Disorder (ASD). One hundred and twenty youth with ASD and their caregivers completed questionnaires assessing these variables. Results showed that greater autism symptoms predicted higher rates of victimization by peers and proactive aggression. Victimization by peers also predicted higher proactive aggression. Mediation analyses found that victimization by peers partially mediated the relationship between autism symptoms and proactive aggression. However, autism symptoms and victimization did not predict reactive aggression. This suggests that social factors like peer victimization may influence proactive but not reactive aggression in youth with ASD.
The document summarizes the Mississippi Library Commission's role in advising and assisting libraries across the state since 1926. It also describes how bookmobiles bring library services to rural areas and how card catalogs have been replaced with electronic search systems. The practicum involved creating a finding aid with metadata to describe scanned pictures of Mississippi libraries, which will be uploaded to a digital archive for public access.
Hikvision Digital Technology Co., Ltd. is one of the world's leading suppliers of video surveillance products and solutions. It was established in 2001 in China and has grown to employ over 6,000 people, including 2,000 R&D engineers. Hikvision offers a wide range of video surveillance equipment such as hybrid DVRs, NVRs, IP cameras, and has a global operation with offices in several regions. It has been recognized as the number one DVR supplier and is now publicly listed on the Shenzhen Stock Exchange with a market capitalization of $5.6 billion.
This presentation contains some of the things that I learned during my practicum at the Mississippi Library Commission. I learned a lot about the history of public libraries in Mississippi, and about the Mississippi Library Commission.
Este documento describe un estudio que evaluó la expresión y frecuencia del gen de fusión formado entre Rad51C y ATXN-7 en tumores colorrectales. Los métodos incluyeron análisis de tejidos tumorales, PCR, clonación y tinción de inmunofluorescencia. Los resultados mostraron que la fusión génica estaba ausente en la vía de reparación del DNA FA y se expresaba en líneas celulares de cáncer colorrectal. El tratamiento con 5-azacitidina aumentó la expresión de la fusión. Las células
Jason Ramlogan has over 20 years of experience in maintenance roles. He is currently the Maintenance Supervisor at YARA Trinidad ASA, where he has worked for the past 7 years. In this role, he oversees the preventative maintenance program and planning and execution of emergency and planned jobs. He previously worked at several other companies in Trinidad in senior mechanical technician and maintenance roles. Ramlogan has a Mechanical Engineering Technician Diploma and has undertaken extensive training in areas like vibration diagnostics, gas seals, and safety.
This document summarizes research on the relationship between college-aged youngest siblings and their older siblings. It reviewed literature showing that birth order impacts how siblings interact and the roles they take on. Research found that youngest siblings often feel closer to their mothers than other siblings and value support from their older siblings. The purpose of the study was to understand how these relationships change as siblings age by interviewing college students about their relationships with older siblings.
This document summarizes a research article that examines the prevalence and outcomes of sibling violence. Some key findings:
1) The study uses survey data from over 8,000 secondary school students to estimate rates of sibling abuse and examine its relationship to substance use, delinquency, and aggression.
2) Results suggest sibling violence occurs more frequently than other forms of child abuse. Sibling violence is significantly associated with substance use, delinquency, and aggression even after controlling for other family violence.
3) The study tests feminist theory and social learning theory to help explain why sibling violence occurs. Younger siblings and females are hypothesized to be more likely victims due to power imbalances, and children may learn abusive behaviors
International Journal of Humanities and Social Science Invention (IJHSSI)inventionjournals
International Journal of Humanities and Social Science Invention (IJHSSI) is an international journal intended for professionals and researchers in all fields of Humanities and Social Science. IJHSSI publishes research articles and reviews within the whole field Humanities and Social Science, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online
The study examined how peer networks of female college freshmen related to their romantic involvement. It found that freshmen who were not dating had significantly more female friends and friends living on campus than those who were in a relationship. This suggests that non-dating freshmen felt more comfortable with close social support networks of other females and those nearby. However, the study found few other significant differences and its hypothesis that dating freshmen would have larger, more gender diverse networks was not supported. Limitations included condensed data that ignored cultural and age differences.
The document discusses several studies that examined the relationship between corporal punishment and aggressive behavior in children. The Hicks-Pass study found that children who were spanked had an increase in aggressive behavior towards others and themselves. The Straus and Mouradian study indicated that the more a child was subjected to corporal punishment, the more they developed antisocial behaviors. Another study found that children from homes where neither parent used physical punishment were the least aggressive. While many factors are involved, the studies generally found links between corporal punishment and increased aggression in children.
Violence prevention programs an exploratory study of the chojas18
This document summarizes a study that examined characteristics of youth who participated in a court diversion program for family violence offenses to determine what characteristics prevented completion. The study found that delinquency characteristics like prior violent arrests and school truancy significantly impacted completion rates. Specifically, youth with these risk factors were less likely to successfully complete the program. The findings suggest a more tailored intervention approach is needed for high-risk, multi-problem youth to address recidivism.
The relationship between types ofchildhood victimisation andojas18
This study examined the relationship between different types of childhood victimization (such as physical abuse, neglect, witnessing violence) and criminal behavior in young adulthood. The researchers analyzed data on over 2,000 young Swedish adults who reported experiencing at least one form of childhood victimization. They found that experiences of physical assault, neglect, and witnessing violence as a child were significantly associated with criminal behavior in young adulthood, even after accounting for gender, substance use, and psychopathy. However, experiences of property crimes, verbal abuse, or sexual abuse were not significantly linked to later criminal behavior. This suggests that childhood experiences involving direct violence or witnessing violence carry the greatest risk for criminal behavior in adulthood.
1. The study examined the relationship between social stressors (low parental warmth, peer victimization) experienced in early adolescence and later neural response to rewards and depressive symptoms.
2. Low parental warmth was associated with increased neural response to potential rewards in the medial prefrontal cortex, striatum, and amygdala. Peer victimization was associated with decreased response in the medial prefrontal cortex.
3. Concurrent depressive symptoms at age 16 were associated with increased reward anticipation response in medial prefrontal cortex and striatal regions. Response in these regions mediated the association between early social stressors and later depressive symptoms.
This study examined trajectories of callous-unemotional (CU) traits in a sample of 1,170 male adolescent offenders to predict later violence and substance use. It identified three trajectories of CU traits (low, moderate, high) and found that membership in the high CU trajectory, particularly combined with elevated early conduct problems, predicted higher levels of violence and substance use over time. It also found that the effects of high CU trajectory combined with elevated conduct problems were stronger for those with higher executive control. This highlights how identifying subgroups based on CU trajectories can improve understanding of developmental pathways leading to severe antisocial behavior.
Children exposed to domestic violence can experience psychological effects like anxiety disorders, PTSD, loss of interest in school, substance abuse, and delinquency. They may also have difficulty forming healthy relationships and exhibit self-blame. Witnessing domestic violence can cause increased sensitivity to anger as well as sadness, fear, and stress responses. Exposure to violence and trauma can neurologically impact brain development and potentially lead to the development of abusive personalities. Some states are now considering child exposure to domestic violence a separate criminal charge. Further research is needed using broader definitions of violence and examining health and medical consequences.
Parental Low Self-Control, Family Environments, and Juvenile DelinquencyGeorge Connolly
This study examines the relationship between parental low self-control, family environments, and officially recorded juvenile delinquency. The study hypothesizes that parental low self-control will be associated with poorer family environments (more conflict, less cohesion) and less effective parenting, and will also be associated with greater juvenile delinquency. It further hypothesizes that the effect of parental low self-control on delinquency will be mediated by family environment factors. The study uses survey data from parents of 101 juveniles involved in the juvenile justice system, along with official records of the juveniles' delinquency charges, to test these hypotheses.
Domestic violence psychologically affects victims and families in several ways. It can cause health issues for victims like depression, substance abuse, and chronic illness. Witnessing domestic violence can negatively impact children's development and behavior, lowering IQs and increasing aggression and emotional problems. Exposure to domestic violence has also been linked to intergenerational cycles of abuse, with children of abuse being more likely to become future victims or abusers themselves. Treatment for abusers and support for victims is important to help break these harmful cycles.
This study compared autism and internalizing symptoms in girls and boys with autism spectrum disorders (ASD) between ages 8-18, as well as typically developing girls and boys. It found that girls with ASD showed similar levels of autism symptoms as boys with ASD, and higher levels of internalizing symptoms like depression compared to boys with ASD and typically developing girls during adolescence. The study suggests that girls with ASD resemble boys with ASD in terms of autism traits, but may be at increased risk for conditions like depression as teenagers due to both their ASD and female sex.
Association Between Relationship Quality and Childhood Trauma in Emerging Ad...John Mattscheck, M.A.
This study examined the relationship between childhood trauma and relationship quality in emerging adults. Researchers surveyed 1,904 college students about their trauma history and relationship beliefs, skills, and quality. Results showed that experiencing more childhood trauma was associated with lower quality relationships with parents and grandparents, but not with siblings or friends. There was no significant relationship found between trauma and students' relationship beliefs or interpersonal skills. The researchers hypothesized that resilience and support from non-family relationships may help explain why trauma did not negatively impact all areas of relationships.
In this paper, I researched how aspects of personality can influence behavior; the specific example here is infidelity. I synthesized the data of multiple experiences to create a personality profile of a person who is more likely to cheat on a romantic partner than the "average" person.
This study examined the relationship between autism symptoms, victimization by peers, and aggression in youth with Autism Spectrum Disorder (ASD). One hundred and twenty youth with ASD and their caregivers completed questionnaires assessing these variables. Results showed that greater autism symptoms predicted higher rates of victimization by peers and proactive aggression. Victimization by peers also predicted higher proactive aggression. Mediation analyses found that victimization by peers partially mediated the relationship between autism symptoms and proactive aggression. However, autism symptoms and victimization did not predict reactive aggression. This suggests that social factors like peer victimization may influence proactive but not reactive aggression in youth with ASD.
The document summarizes the Mississippi Library Commission's role in advising and assisting libraries across the state since 1926. It also describes how bookmobiles bring library services to rural areas and how card catalogs have been replaced with electronic search systems. The practicum involved creating a finding aid with metadata to describe scanned pictures of Mississippi libraries, which will be uploaded to a digital archive for public access.
Hikvision Digital Technology Co., Ltd. is one of the world's leading suppliers of video surveillance products and solutions. It was established in 2001 in China and has grown to employ over 6,000 people, including 2,000 R&D engineers. Hikvision offers a wide range of video surveillance equipment such as hybrid DVRs, NVRs, IP cameras, and has a global operation with offices in several regions. It has been recognized as the number one DVR supplier and is now publicly listed on the Shenzhen Stock Exchange with a market capitalization of $5.6 billion.
This presentation contains some of the things that I learned during my practicum at the Mississippi Library Commission. I learned a lot about the history of public libraries in Mississippi, and about the Mississippi Library Commission.
Este documento describe un estudio que evaluó la expresión y frecuencia del gen de fusión formado entre Rad51C y ATXN-7 en tumores colorrectales. Los métodos incluyeron análisis de tejidos tumorales, PCR, clonación y tinción de inmunofluorescencia. Los resultados mostraron que la fusión génica estaba ausente en la vía de reparación del DNA FA y se expresaba en líneas celulares de cáncer colorrectal. El tratamiento con 5-azacitidina aumentó la expresión de la fusión. Las células
Jason Ramlogan has over 20 years of experience in maintenance roles. He is currently the Maintenance Supervisor at YARA Trinidad ASA, where he has worked for the past 7 years. In this role, he oversees the preventative maintenance program and planning and execution of emergency and planned jobs. He previously worked at several other companies in Trinidad in senior mechanical technician and maintenance roles. Ramlogan has a Mechanical Engineering Technician Diploma and has undertaken extensive training in areas like vibration diagnostics, gas seals, and safety.
Este documento presenta un plan de estudios para estudiantes de licenciatura en educación física. El objetivo es que los estudiantes aprendan las características y estructura de una sesión de educación física a través de la observación de sesiones, planeación e implementación de sus propias sesiones durante su práctica docente. El plan incluye recursos, diseño, implementación y evaluación para guiar a los estudiantes en el desarrollo y aplicación de tres sesiones completas de educación física con diferentes grupos de al
This study examined whether individual differences in infant temperament, as assessed in a biobehavioral assessment between 3-4 months of age, predicted the formation of affiliative relationships in 57 rhesus macaque yearlings. The researchers observed the yearlings over a 10-week period to record affiliative behaviors like proximity, play, contact and grooming. They found that yearlings who had scored high on "equability" as infants, indicating calmness and low activity, had fewer peer relationships. Yearlings also preferentially affiliated with peers who had similar scores on equability and adaptability from the infant assessment. Even after controlling for factors like kinship, rank and sex, infant temperament remained a significant predictor of variation
This document discusses Vantech's smart home monitoring solutions, including:
- Four-in-one digital recorders that support AHD, TVI, IP, and analog cameras.
- Connectivity to cameras, cloud, and mobile devices for remote monitoring.
- Wireless alarm devices like smart plugs, motion sensors, door sensors, and sirens.
- Easy setup and user-friendly interfaces for monitoring on computers and mobile apps.
DNA structure, genes and its chemical compositionValentina Duque
The document discusses the importance of understanding DNA structure and genes. It notes that DNA contains the genetic material of organisms and understanding a person's DNA can help identify genetic mutations that may cause diseases. This allows for focused treatment and prevention strategies. The document also discusses two recent studies: one discovered a new gene variant present in 3% of ALS cases, and the other found genetic variants linked to academic achievement that can help identify children at risk for learning difficulties. Understanding DNA structure is thus essential for medicine and treatment.
RUNNING HEADER COURSE PROJECT – INTRODUCTION AND REFERENCES1.docxagnesdcarey33086
RUNNING HEADER: COURSE PROJECT – INTRODUCTION AND REFERENCES 1
COURSE PROJECT – INTRODUCTION AND REFERENCES 2
Paper Week 06
Course Project – Introduction and References
Tania Hoffman
Rasmussen College
Author Note
This paper is being submitted November 16, 2014 for Cari Beecham-Bautista, M.A. G142/SYG1000 Section 14 Introduction to Sociology.
Course Project – Introduction and References
We all want the best for our children and the children around us. The children in today’s society are the adults in tomorrow’s society. I have three children at home myself with a very supportive husband and family and friends around me. All three children have different attitudes and different behavioral issues that need addressing on a daily basis. You see the children out on the street, see the news and crimes happening all around us and don’t you wonder what is going on and why? Asking yourself, where are the parents!? I know I am guilty of just that.
Sociologists have become increasingly concerned with the ways in which families shaped children’s development and overall well-being. Sociologist’s examine the timing and duration of mothers’ poverty, single motherhood, welfare, employment, and kin coresidence through early and middle childhood. Child behavior problems are shaped by poverty and kin coresidence in early and middle childhood, and by parents use of physical punishment. Data was used on mothers and children from the NLSY, which showed strong demands of data, and provided strong tests of relationships.
A child’s behavior problems are a very important aspect of children development because it could be implicated in later adult outcomes. For example child temper tantrums could lead to later problems in life such as downward occupational mobility, erratic work lives, and divorce and separation (Caspi, Elder, and Bem 1987). Child development research find continuity between early behavior problems and later antisocial behavior (Olweus 1979; Loeber 1982), while criminological research finds continuity between behavior problems and later delinquency and crime (Farrington 1986; White et al. 1990). Such offenders in turn are more likely to suffer adult problems like joblessness, poverty, violence, and imprisonment (Nagin, Farrington, and Moffitt 1995; Farrington 1989; Hagan 1991).
Through the research in child psychology it has been determined that coercive or authoritarian control based upon force, threat, or physical punishment of children is ineffective in controlling and shaping children. What has been proved effective is inductive or authoritative control based upon reasoning, explaining, and understanding (Baumrind 1978; Boronfenbrenner 1979; Rollins and Thomas 1979).
Child development and parent child interactions have a large deal to do with social structure. For example this includes everything from parents working outside of the home which could impede parent-child interactions and increase problems. Then there i.
- The document discusses studies on attachment parenting in non-human subjects like monkeys and geese and what they reveal about the importance of early parental relationships.
- Experiments by Harlow on monkeys found that they preferred and gained more emotional comfort from a cloth surrogate mother rather than a wire one that just provided food, showing the importance of emotional relationships over just basic care.
- Studies on geese found they would imprint on and form strong early bonds with their mothers or even researchers, increasing chances of survival, relating to the importance of early bonding for humans.
- Overall, the non-human studies demonstrate that positive, nurturing early parental relationships are vital for healthy emotional and social development across species, while lack of care or
This literature review examines psychosocial factors that can influence a child's recovery from traumatic brain injury (TBI). Several studies identified elements like family functioning, parenting styles, socioeconomic status, and the parent-child relationship as being able to either enhance or hinder recovery. Common themes indicated that greater parental involvement, warmth, and healthier family dynamics can help in recovery, while lower SES, more negative family behaviors, and dysfunctional parenting are linked to poorer outcomes. Future research should explore how early intervention may help address harmful elements and maximize a child's recovery potential, including studying the role of sibling relationships.
Does Parental Sexual Orientation Matter A Longitudinal FollowDustiBuckner14
Does Parental Sexual Orientation Matter? A Longitudinal Follow-Up of
Adoptive Families With School-Age Children
Rachel H. Farr
University of Kentucky
Controversy continues to surround parenting by lesbian and gay (LG) adults and outcomes for their
children. As sexual minority parents increasingly adopt children, longitudinal research about child
development, parenting, and family relationships is crucial for informing such debates. In the psycho-
logical literature, family systems theory contends that children’s healthy development depends upon
healthy family functioning more so than family structure. From the framework of family stress theory,
it was expected that longitudinal outcomes for school-age children adopted in infancy could be distinct
among those with same-sex versus other-sex parents (N � 96 families). Similar findings were hypoth-
esized in terms of parent adjustment, couple relationships, and family functioning in comparing same-sex
and other-sex parent families. Results indicated that adjustment among children, parents, and couples, as
well as family functioning, were not different on the basis of parental sexual orientation (lesbian, gay, or
heterosexual) when children were school-age. Rather, children’s behavior problems and family func-
tioning during middle childhood were predicted by earlier child adjustment issues and parenting stress.
These findings are consistent with and extend previous literature about families headed by LG parents,
particularly those that have adopted children. The results have implications for advancing supportive
policies, practices, and laws related to adoption and parenting by sexual minority adults.
Keywords: middle childhood, parenting stress, couples, adoptive families, sexual orientation
Americans remain divided about their views on lesbian and gay
(LG) adults raising children, according to the Pew Research Center
(e.g., Daugherty & Copen, 2016). Controversy often centers on
whether children need a mother and a father for optimal develop-
ment, yet theoretical perspectives tend to emphasize the impor-
tance of high-quality parenting and family relationships, rather
than family structure (Lamb, 2012). Outcomes for children with
LG parents have been featured in legal and policy debates about
same-sex marriage and the adoption of children. How children fare
with same-sex parents was a pivotal consideration in the June 2015
Supreme Court decision about marriage equality (Obergefell v.
Hodges; e.g., American Psychological Association, 2015). Despite
debate, millions of sexual minority (i.e., nonheterosexual) adults
desire to be parents and many are already parents, including
adoptive parents (Riskind & Patterson, 2010). During recent years,
the number of adoptive LG parents has doubled (Gates, 2011).
According to 2010 Census data, same-sex couples are four times
more likely than other-sex couples to adopt children (Gates, 2013).
From data representing couples and single parents (2000 Census, ...
Bullying in childhood can have long lasting negative effects. Victims are more likely to experience mental health issues like depression, anxiety, and low self-esteem that may persist into adulthood. Longitudinal studies show childhood victims are at higher risk as adults for disorders like depression, anxiety, antisocial personality disorder, and suicide attempts. Victims also tend to have poorer social relationships, economic difficulties, and lower quality of life in mid-life compared to non-victims. The effects of bullying can last decades and negatively impact both psychological and physical health.
Article Summary Table – Template 2
Full Reference
Research Question(s)
Sample
Method
Data
Findings
Evaluation
Smetana, J. G., & Gettman, D. C. (2006). Autonomy and relatedness with parents and romantic development in African American adolescents. Developmental Psychology, 42(6), 1347-1351. doi:10.1037/0012-1649.42.6.1347
1. Less autonomy and more relatedness in early adolescence would lead to later starting of romantic relationships and better quality romantic relationships, including more supportive and less negative romantic relationships during late adolescence.
2. Early adolescents with high levels of relatedness to parents and low to moderate levels of autonomy in family decision making would report later starting of romantic careers and more positive romantic relationships five years later than would other youth.
The study sample involved seventy-six middle-class adolescents (half female, half male) of the African American race of the final wave of the study. These adolescents were in various phases of their lives with some in their junior or senior year of high school, some in the process of enrolling in college, some already enrolled in college, some employed, and some in the military. It is important to note that nearly one hundred percent of these adolescents described themselves as being single. With the middle-class parents who were included, majority of them had some college instruction, over half grossed over seventy thousand dollars a year, and about half were in steady marriages for longer than the time the study was conducted.
This research was a qualitative method because it gave a thorough understanding of the research topic; it used the population’s point of view; and it focused on the opinions and behaviors of the population.
There were three waves. For the first wave, an interview was given. Wave three involved questionnaires five years after the first wave. No information was specified about wave two.
Data collected focused on autonomy and relatedness on different levels. Measures that were used during research included interviews and questionnaires/surveys. The type of data that was collected within the interview was the evaluation of autonomy and relatedness. There were numerous questionnaires/surveys given to the subjects.
Those that were used included a scale for family decision making for the autonomy aspect of research, the Trust and Communication subscales of the Parent-Peer Attachment Inventory, the Romantic History Survey, and the Network of Relationships Inventory.
The scale that was used for family decision making assessed just that. The Trust and Communication subscales of the Parent-Peer Attachment Inventory measured closeness and connection to parents. The Romantic History Survey determined romantic involvement. The Network of Relationships Inventory calculated positive social support and undesirable interactions.
The authors Smetana and Gettman (2006) clarified their results in a cl.
Mehta & Strough_2010_ Gender Segregation and Gender-typing in AdolescenceClare Mehta
This document summarizes a research study that investigated correlates of gender segregation among adolescent boys and girls. The study found that 72% of peers nominated for hanging out were the same gender as the adolescent. Girls' gender segregation was correlated with stronger gender identity and a belief that girls are more communicative partners than boys. The study considered how gender segregation relates to aspects of identity development and gender-typing during adolescence.
Does Gender Affect Stepchild Relations with StepparentsKelsey Duff
This document summarizes a literature review on stepparent-stepchild communication. It discusses 3 main themes from previous research: 1) Traditional gender roles influence relationships, with stepmothers typically finding it harder to connect and stepfathers having more success. 2) Engagement level affects satisfaction, with more casual everyday conversations leading to better relationships than serious talks. 3) Speed of communication impacts relationships, with slower development of relationships over time being better received than rushed relationships. The literature review identifies gaps such as lack of diversity in studied populations and opportunities to study stepchild gender influences. This leads to the author's research question of how gender differences between stepparent and young adult influence their communication.
Child Gender Influences Paternal Behavior, Language, and Brain.docxbartholomeocoombs
Child Gender Influences Paternal Behavior, Language, and Brain Function
Jennifer S. Mascaro
Emory University
Kelly E. Rentscher
University of Arizona
Patrick D. Hackett
Emory University
Matthias R. Mehl
University of Arizona
James K. Rilling
Emory University
Multiple lines of research indicate that fathers often treat boys and girls differently in ways that impact
child outcomes. The complex picture that has emerged, however, is obscured by methodological
challenges inherent to the study of parental caregiving, and no studies to date have examined the
possibility that gender differences in observed real-world paternal behavior are related to differential
paternal brain responses to male and female children. Here we compare fathers of daughters and fathers
of sons in terms of naturalistically observed everyday caregiving behavior and neural responses to child
picture stimuli. Compared with fathers of sons, fathers of daughters were more attentively engaged with
their daughters, sang more to their daughters, used more analytical language and language related to
sadness and the body with their daughters, and had a stronger neural response to their daughter’s happy
facial expressions in areas of the brain important for reward and emotion regulation (medial and lateral
orbitofrontal cortex [OFC]). In contrast, fathers of sons engaged in more rough and tumble play (RTP),
used more achievement language with their sons, and had a stronger neural response to their son’s neutral
facial expressions in the medial OFC (mOFC). Whereas the mOFC response to happy faces was
negatively related to RTP, the mOFC response to neutral faces was positively related to RTP, specifically
for fathers of boys. These results indicate that real-world paternal behavior and brain function differ as
a function of child gender.
Keywords: experience sampling, fathers, fMRI, gender socialization, play
Supplemental materials: http://dx.doi.org/10.1037/bne0000199.supp
A number of studies argue that parents treat girls and boys
differently, and learning theory proposes that parents model and
reinforce gender stereotypes in their children (Bandura & Walters,
1977; Bussey & Bandura, 1999). For example, some research
indicates that mothers talk more (Leaper, Anderson, & Sanders,
1998; MacDonald & Parke, 1984) and are more restrictive of
physical risk-taking with daughters (Morrongiello & Hogg, 2004)
than with sons. Other research indicates that western fathers and
mothers are more elaborative in autobiographical storytelling with
girls than boys (Fivush, 2011). Moreover, parents often encourage
gender-stereotyped play behavior and household chores and dis-
courage gender-atypical behavior (Lytton & Romney, 1991), and
both mothers and fathers are more likely to engage in rough and
tumble (RTP) play with boys than with girls (McIntyre & Ed-
wards, 2009; Paquette & Dumont, 2013; Pellegrini & Smith,
1998). Related lines of research also point to differences in paren-
tal behavio.
Parent-child relationships and interactions with peers influence adult relationships. Bowlby's concept of internal working models suggests that early attachment styles shape expectations and behaviors in later relationships. However, research also shows that attachment styles can change based on current relationships and significant life experiences. While early experiences impact adult relationships, it is not deterministic, as individuals can go on to have happy relationships despite early insecurity. Interactions with peers also impact views of self and approaches to relationships, though experiences differ between genders. Some studies find adolescent relationships can affect adult ones, but not all research agrees on this.
Peer Response Unit 5 LifespanResponse Guidelines for both peer r.docxrandyburney60861
Peer Response Unit 5 Lifespan
Response Guidelines for both peer responses (#1 and #2)
Your responses to other learners are expected to be substantive in nature and to reference the assigned readings, as well as other theoretical, empirical, or professional literature to support your views and writings. Use the following critique guidelines:
The clarity and completeness of your peer's post.
The demonstrated ability to apply theory to practice.
The credibility of the references.
The structure and style of the written post.
Peer Response #1
A.Flogel
Adolescence is a time of high emotional reactivity and development of social identity. Adolescents learn who they are in relation to others while at the same time experiencing more mood disruption than any other stage of life. At this stage, development from early experiences has already impacted them and how they feel about and interact with peers. This along with the fact that the frontal lobe of the brain, responsible for higher order fuctioning such as self-regulation and judgment, is not fully developed, can explain why this stage gives way to risky behaviors (Broderick & Blewitt, 2014). One particularly troubling behavior in adolescents is drug use. Not only is this harmful to the individual at the time, but it often leads to lifelong difficulty with addiction. There are several risk factors that can increase the likelihood of drug use in adolescence.
One very relevant factor to drug use is self-concept, which starts developing in early childhood, but especially develops in adolescence. This can include one's physical, social, family, and academic self-concept. A study that analyzed the relationship between self-concept and drug use found that negative self-concept in categories of family, academics, and physical appearance was significantly correlated with drug use (Maria et al., 2011).
Another factor highly correlated with drug use is exposure to "potentially traumatic events" prior to age 11. These events include threats to physical or emotional harm. The Journal of the American Academy of Child & Adolescent Psychiatry published a study using a national survey examining the link between these PTEs and drug use in adolescence, and found a positive relationship between PTEs and use of marijuana, cocaine, and prescription drugs (Carliner et al., 2016).
Although much evidence has been found regarding environmental influences, heritability also plays a role. A longitudinal study found that heritability of externalizing behavior in adolescents was 56%, and 27% for drug use (Korhonen et al., 2012).
These factors often interact with each other. For example, when a parent is genetically inclined to externalize, often the parent will abuse drugs, creating an unstable environment for their child. They may be less responsive in early childhood, creating an insecure attachment and a poor self-concept. Parental drug use and general externalizing behavior may also expose a child to potenti.
Dyadic Coping and Attachment Dimensions in Young Adult Romantic RelationshipsAJHSSR Journal
ABSTRACT: Dyadic coping conceives coping as a response in which partners support each other
and cope with stress as a couple rather than individuals, but little is known of the factors that lead to
dyadic coping. The present study aims to explore the relationship between dyadic coping and adult
attachment. That is, to examine whether an individual’s attachment style is a predictor of their own
dyadic coping style and their partner’s dyadic coping style. Online, survey data was collected from 74
childless couples, between the ages of 18 and 31, who had been in their relationships for over 6
months. Overall, analysis showed stronger associations between dyadic coping and attachment for
females, with minimal associations for males. The results of the present study are supportive of the
existing literature, though provide opportunities for further research.
KEYWORDS: dyadic coping, coping, attachment, romantic relationships, APIM
Wilson et al (2014) Prompt Dependency Beyond ChildhoodBronwyn M Wilson
This document summarizes a research study that explored prompt dependency in adults with Asperger's syndrome and their relationships with neurotypical partners. The study found that adults with Asperger's syndrome showed prompt dependency in their interactions with their partners. Prompt dependency formed a cycle within the interactions of these couples that impacted their ability to communicate and relate to each other intimately. In-depth interviews were conducted with nine couples to explore this phenomenon and its effects on their relationships.
This document summarizes a study that investigated the effects of maternal separation and cannabinoid receptor antagonism on anxiety and social behaviors in rats. The study found that early life stress from maternal separation increased anxiety-like behaviors and aggression in adulthood. Treatment with a cannabinoid receptor antagonist had varying effects on behaviors depending on sex and early life stress exposure. Analysis of interneuron populations in the prefrontal cortex suggested changes in these cells may underlie behavioral alterations.
2019 verhagen a snp_gene_polygenic risk score oxt_vasopressin genes_lonelinessDesiyani Nani
This study examines genetic factors associated with loneliness in adolescents using two longitudinal samples. It analyzes genes in the oxytocin-vasopressin pathway (OXT, OXTR, AVPR1A, AVPR1B) using single nucleotide polymorphism (SNP)-based, gene-based, and polygenic risk score approaches. In both samples, the OXTR gene showed involvement in loneliness development over time, though significance did not survive multiple testing corrections. The polygenic risk score approach provided no evidence of associations. The study recommends alternative phenotyping methods and epigenetic studies to further examine genetic influences on adolescents' loneliness.
14Gender and SexualitySeverin SchweigerCulturaGetty Imag.docxaulasnilda
14Gender and Sexuality
Severin Schweiger/Cultura/Getty Images
Learning Objectives
After completing this module, you should be able to:
ሁ Outline the biological, social, and cognitive explanations for the emergence of gender identity.
ሁ Form evidence-based arguments on gender differences in development.
ሁ Summarize the developmental imperative of physical activity for boys and girls during childhood.
ሁ Compare and contrast school achievement and learning between boys and girls.
ሁ Describe differences and similarities among heterosexual girls, heterosexual boys, and LGBT
adolescents with regard to romantic relationships and identity formation.
ሁ Discuss the psychological effects of puberty.
ሁ Evaluate ethnic and national differences in sexual activity among adolescents; explain the
consequences of teenage pregnancy.
ሁ Identify different health outcomes of sex during adolescence, including categorizing STIs and the
effects of HIV among infected children worldwide.
Section 14.1The Development of Gender
Prologue
Recent stories have led to renewed discussion about sex and gender in society. Sasha Lax-
ton from Great Britain; Storm Stocker from Toronto, Canada; and Pop from Sweden have all
made headlines as their parents were determined to raise them without regard to gender. The
children’s rooms were painted in neutral colors; hairstyles, Halloween costumes, and cloth-
ing were chosen without perceived regard for gender standards; exposure to toys and other
activities were not limited by what was considered “normal” for a boy or a girl.
As a result, there has been considerable debate among parents, academics, and the media
about the potential detriment—and benefit—if children are not aware of how they are “sup-
posed” to behave. However, these families are also quite outside the mainstream. It takes
tremendous effort to rid a child of messages related to gender, including limiting exposure
to media, avoiding certain store shelves, and restricting access to preschool and other social
activities.
For most children, though, sex and gender are inescapably connected. It is extremely rare for
a child to be born with undifferentiated sex organs. Even so, those children still generally have
either XX or XY genes. Biological sex is therefore not particularly variable. By contrast, regard-
less of biological sex, gender is much more continuous. Some children are drawn quite strongly
to the behaviors and activities of one gender over another, whereas other children engage
freely in more varied activities. This module explores these issues, as well as concerns related
to adolescent sex and romantic relationships and their developmental consequences.
14.1 The Development of Gender
Recall the many different factors involved in the development of the self and the formation
of gender identity (see Module 12). Gender is a key component in the development of the
self. In psychology, gender refers to the meanings societies and ...
This study examined the relationship between childhood socioeconomic disadvantage, adolescent neural response to rewards, and depression in 123 girls. The researchers found that greater years receiving public assistance during childhood was associated with heightened response in the medial prefrontal cortex during reward anticipation. This heightened neural response mediated the relationship between childhood socioeconomic disadvantage and current depression symptoms in adolescence, after controlling for past depression. The findings suggest that chronic exposure to low socioeconomic status in childhood may alter neural circuits involved in reward processing, conferring risk for later depression.
1) The study examined loneliness in 84 children and adolescents diagnosed with ADHD and compared them to 84 non-ADHD individuals matched for age and gender.
2) A multidimensional measure of loneliness called the Perth A-Loneness scale (PALs) was administered and a four factor model including friendship loneliness, isolation, negative attitude to solitude, and positive attitude to solitude fit the data best.
3) Results found no significant differences between the ADHD and non-ADHD groups in levels of loneliness as measured by the four factors, indicating that loneliness is experienced similarly in children and adolescents with and without ADHD.
Genetic Influences on Parental Expressed Emotion. A Novel Approach to the Nat...Florence Walsh
This document summarizes a study that examines genetic influences on parental expressed emotion using a child-based twin design. The study measured expressed emotion using the Five Minute Speech Sample (5MSS) in which mothers spoke for five minutes about their twins. Previous research found some genetic effects for self-reported parenting measures but no genetic effects for the 5MSS measure, indicating mothers spoke about twins very differently. The study demonstrates how the 5MSS can provide insight into parental differential treatment and the bidirectional nature of parent-child relationships. It offers a perspective on how both children and parents can influence each other due to genetic factors.
Similar to Weinstein 2014 Neuropeptides and Friendship (20)
Genetic Influences on Parental Expressed Emotion. A Novel Approach to the Nat...
Weinstein 2014 Neuropeptides and Friendship
1. BEHAVIORAL NEUROSCIENCE
ORIGINAL RESEARCH ARTICLE
published: 28 August 2014
doi: 10.3389/fnbeh.2014.00295
Early involvement in friendships predicts later plasma
concentrations of oxytocin and vasopressin in juvenile
rhesus macaques (Macaca mulatta)
Tamara A. R. Weinstein1
*, Karen L. Bales1
, Nicole Maninger1
, Caroline M. Hostetler1,2
and
John P. Capitanio1
1
California National Primate Research Center, University of California, Davis, CA, USA
2
Department of Behavioral Neuroscience, Oregon Health and Science University, Portland, OR, USA
Edited by:
Lisa A. Parr, Emory University, USA
Reviewed by:
René Hurlemann, University of
Bonn, Germany
Lisa A. Parr, Emory University, USA
*Correspondence:
Tamara A. R. Weinstein, California
National Primate Research Center,
University of California, One Shields
Avenue, Davis, CA 95616, USA
e-mail: tarweinstein@ucdavis.edu
The neuropeptides oxytocin (OT) and arginine vasopressin (AVP) are involved in social
bonding in attachment relationships, but their role in friendship is poorly understood. We
investigated whether rhesus macaques’ (Macaca mulatta) friendships at age one predicted
plasma OT and AVP at two later time points. Subjects were 54 rhesus macaques at
the California National Primate Research Center (CNPRC). Blood was drawn during a
brief capture-and-release in the home cage, and plasma assayed for OT and AVP using
an enzyme immunoassay (EIA). Separate linear mixed models for each sex tested the
effects of dominance rank, age, sampling time point, housing condition, parturition status,
two blood draw timing measures, and five friendship types: proximity friendships, play
friendships, reciprocal friendships (a preference for a peer that also preferred the subject),
multiplex friendships (friendships displayed in more than one behavioral domain), and total
number of friendships. Females’ number of reciprocal and play friendships at age one
significantly predicted later OT; additionally, these two friendship types interacted with
rank, such that high-ranking females with the fewest friendships had the highest OT
concentrations. Friendship did not predict later OT levels in males, however proximity,
play, reciprocal, and total number of friendships predicted males’ plasma AVP. Play and
total number of friendships also tended to predict AVP in females. Our results show
that peripheral measures of neuroendocrine functioning in juvenile rhesus monkeys are
influenced by early involvement in friendships. Friendships have an especially strong
impact on an individual’s psychosocial development, and our data suggest OT and AVP as
potential underlying mechanisms. Moreover, sex differences in the functioning of the OT
and AVP systems, and their relation to friendship, may have important clinical implications
for the use of OT as a therapeutic, as well as informing the social context in which it is
administered.
Keywords: affiliation, friendship, oxytocin, rhesus macaque, social behavior, vasopressin
INTRODUCTION
Friendships are critically important for healthy development
throughout the lifespan, and a lack of friends increases vulner-
ability to mental disorders such as depression, physical illnesses
such as cardiovascular disease, and mortality (Cohen and Wills,
1985; House et al., 1988; Uchino et al., 1996; Thorsteinsson
and James, 1999). Friendships are particularly vital for successful
psychosocial adjustment in children, and greater involvement in
friendships is associated with more positive school perceptions
and performance gains in kindergartners (Ladd, 1990), decreased
feelings of loneliness and depression in 3rd-6th graders (Nangle
et al., 2003), lower levels of teacher reported maladjustment
during adolescence (Waldrip et al., 2008), and decreased loneli-
ness and self-reported victimization in adolescents suffering from
social anxiety (Erath et al., 2010). Preadolescence may be an
especially critical time period for the successful development of
adult social skills and ties (Fullerton and Ursano, 1994), and
the consequences of friendship formation during this period
may be far reaching; for example, friended preadolescents report
higher levels of self-worth in adulthood when measured 12 years
later, while the absence of friendship is associated with psy-
chopathological symptoms in adulthood (Bagwell et al., 1998).
It is notable that while having high quality, supportive rela-
tionships both with attachment figures (i.e., parents) and with
peers impacts children’s psychosocial development, having high
quality peer friendships can buffer the negative consequences
experienced by children with low parental support (Rubin et al.,
2004).
Nonhuman primate friendships are characterized by many
of the same features as human friendships (Smuts, 1985; Silk,
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 1
2. Weinstein et al. Rhesus macaque friendship and neuropeptides
2002), and are linked to many similarly beneficial consequences.
Having strong, long-lasting friendships enhances longevity, infant
offspring survival, and offspring longevity (Silk et al., 2003, 2009,
2010), and friends buffer individuals’ behavioral and physiolog-
ical responses to stressors (Higley et al., 1992; Gust et al., 1994;
Boccia et al., 1997; Beehner et al., 2005; Crockford et al., 2008;
Wittig et al., 2008). As with human children, befriending peers is
vital for nonhuman primate youngsters to establish independence
from their mothers and successfully integrate themselves into the
wider network of their social group (Hinde and Spencer-Booth,
1967), as well as to learn social skills necessary for successfully
navigating the complex relationships that they will encounter as
adults (Poirier and Smith, 1974; Joffe, 1997). In rhesus macaques
(Macaca mulatta), friendships are clearly identifiable at least as
early as 1 year of age, and, like children’s friendships, their
formation and persistence are influenced by individual-level char-
acteristics such as personality and relationship-level qualities such
as reciprocity (Weinstein and Capitanio, 2008, 2012). Juvenile
rhesus monkeys reap short-term benefits from their friends, such
as an attenuated distress response in a novel context (Higley
et al., 1992), as well as long-term advantages such as facilitat-
ing dominance rank acquisition during adolescence (de Waal
and Luttrell, 1985; Datta, 1988). Rhesus macaques have long
been regarded as a valuable model system in which to exam-
ine socioemotional development, due to the cognitive abilities,
physiological and neuroanatomical characteristics, and socioe-
motional complexity which they share with humans (Suomi,
2005; Capitanio and Emborg, 2008; Weinstein et al., 2008; Nelson
and Winslow, 2009; Weiss et al., 2011), and may therefore be
uniquely capable of filling the large gap that exists between human
and rodent research on the neurobiological basis of affiliative
relationships (Weinstein and Capitanio, 2005). The few studies
thus far that have attempted to close this gap suggest that the
neuropeptides oxytocin (OT) and arginine vasopressin (AVP)
play a key role.
OT and AVP are nine-amino acid peptides produced in the
hypothalamus and released into circulation via the posterior
pituitary (Zingg, 2002). OT and AVP differ only by two amino
acids (Sofroniew, 1985) and can bind to each other’s receptors
(Gimpl and Fahrenholz, 2001). In both nonhumans and humans,
OT plays a role in mother-infant interactions (Pedersen and
Prange, 1979; Feldman et al., 2010b), father-infant interactions
(Feldman et al., 2010a), and adult romantic attachments (Carter
et al., 1995; Cho et al., 1999; Gordon et al., 2008; Scheele et al.,
2012), and AVP underlies male pair-bonding (Winslow et al.,
1993; Cho et al., 1999; Lim and Young, 2004; Jarcho et al.,
2011) and parenting behavior (Wang et al., 1998; Bales et al.,
2004b). Though OT and AVP are rarely studied in the context
of non-attachment relationships such as friendships, they are
strong candidates for several reasons. First, OT has previously
been implicated in behaviors known to be important to friendship
including trust (Zak et al., 2005; Kéri and Kiss, 2011; Zhong
et al., 2012), generosity (Zak et al., 2007; Baumgartner et al.,
2008), social support (Heinrichs et al., 2003; Buchheim et al.,
2009), and reciprocal or synchronous behaviors (Atzil et al.,
2012). Notably, in wild chimpanzees, grooming with a “bond
partner” (defined by mostly positive dyadic social behaviors,
such as grooming, coalitionary support, etc.) resulted in higher
urinary OT levels following grooming, regardless of whether
the bond partner was related or not (i.e., a friend; Crockford
et al., 2013). Second, AVP has a role in enhancing the recog-
nition of emotional states (Guastella et al., 2010) and in sex-
specific perceptions of the friendliness of faces (Thompson et al.,
2006). Finally, OT and AVP can have far-reaching develop-
mental effects on behavior and vice versa (Carter, 2003; Bales
and Perkeybile, 2012; Veenema, 2012). Pharmacological expo-
sure to OT or AVP either at birth (Bales and Carter, 2003a,b;
Bales et al., 2004a, 2007a,b; Gregory et al., 2013), later in the
perinatal period (Stribley and Carter, 1999), or in the peri-
adolescent period (Bales et al., 2013) can have long-term, orga-
nizing effects on social behaviors, anxiety behaviors, and neural
systems. Conversely, early experiences, such as the quality of
parental care received, can shape both humans’ and animals’
neuropeptide response (Bartz et al., 2010; Bales and Perkeybile,
2012; Veenema, 2012; Feldman et al., 2013). Given the impact
of early parental experience on an offspring’s OT and AVP sys-
tems, it is likely that early peer experiences, particularly friend-
ship involvement, would similarly influence later OT and AVP
responses.
In the current study, we examined how friendships in year-
ling rhesus macaque males and females predicted plasma OT
and AVP concentrations approximately 1–3 years later. Though
many animal studies of OT and AVP have measured central
concentrations or receptor distributions, studies of humans rely
almost exclusively on peripheral measures, whose meaning is
still being unraveled, but which may reflect responses to a range
of stimuli, including social stimuli (Kenkel et al., 2012). It is
likely that peripheral levels do not fully capture central levels
(Kagerbauer et al., 2013), although they may be correlated under
certain conditions (Landgraf and Neumann, 2004). It is impor-
tant to continue to examine the utility and predictive value of
peripheral peptide measures, because until non-invasive tech-
nology advances significantly, central measures in living humans
are difficult to obtain. Because previous research has shown
numerous sex differences in baseline neuropeptide concentra-
tions (Kramer et al., 2002; Miller et al., 2013), regulation by
gonadal hormones (Witt et al., 1991; De Vries and Villalba, 1997;
Cushing et al., 2003), and sensitivity to exogenous stimulation
(Carter, 2003, 2007), we hypothesized that we would find sex-
specific associations between plasma OT, AVP, and friendship.
As high peripheral levels of OT and AVP have been associated
with improved social functioning in the case of children with
autism spectrum disorders (Modahl et al., 1998; Green et al.,
2001), we specifically predicted that having more friendships (and
particularly higher-quality friendships) would be associated with
high OT in females and high AVP in males. However, high plasma
OT and AVP levels in adult humans may sometimes be associated
with a social challenge, such as a distressed pair-bond relationship
(Taylor et al., 2006, 2010); therefore an alternate prediction was
that the stress associated with fewer social connections would
result in higher levels of peptides later (presumably, higher OT in
females and higher AVP in males). The most recent data suggest
that OT and AVP levels may often exhibit complex, nonlinear
relationships with social variables; a recent study with a very
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 2
3. Weinstein et al. Rhesus macaque friendship and neuropeptides
large sample showed a U-shaped relationship between OT levels
and trust (Zhong et al., 2012). We therefore also tested whether
friendship involvement in our subjects would demonstrate a non-
linear relationship with neuropeptide levels measured later in
development.
MATERIALS AND METHODS
SUBJECTS AND HOUSING
Subjects were 54 rhesus macaques (29 males) that had partici-
pated in our previous study of yearling friendships (Weinstein and
Capitanio, 2008; note that our original N = 57, however only 54
animals were available for blood sampling for the current study).
Subjects were housed in half-acre (0.19 ha) outdoor breeding cor-
rals at the California National Primate Research Center (CNPRC).
Each corral housed approximately 90–150 animals of all age/sex
classes year-round, and, like wild rhesus monkey troops, groups
were organized around female-headed extended families (matri-
lines). Each corral contained several separate matrilines, which
in turn typically comprised several generations of kin. Corrals
were constructed of chain-link sides and top measuring 30.5 m
wide × 61 m deep × 9 m high, a natural substrate floor, sev-
eral wooden A-frame structures, PVC-coated perches, a variety
of climbing devices, and several food hoppers. Primate labora-
tory chow was provided twice daily, fruit and vegetable supple-
ments were provided twice weekly, and water was available ad
libitum.
For the yearling behavioral data collection portion of the
study, all subjects were housed in the outdoor breeding corrals
described above. However, shortly before the first blood sample
was collected, six subjects were removed from their natal groups
due to social instability. Five of these animals were sampled while
pair-housed in standard indoor living cages measuring 0.58 ×
0.66 × 0.81 m, and one subject was sampled while living in
an outdoor corncrib. Corncrib groups contained 1 adult male
and 3–6 adult females and their offspring, and consisted of two
outdoor cylindrical structures approximately 4 m in diameter
constructed of chain-link fencing and connected by a rectangular
passageway. Like the breeding corrals, corncribs contained PVC
perches, climbing structures, and food hoppers. At the time the
second blood sample was collected, 42 subjects were living in
the outdoor breeding corrals, 8 had been relocated indoors, and
1 subject continued to live in a corncrib.
AFFILIATIVE BEHAVIORAL DATA COLLECTION
We previously described affiliative behavior data collection meth-
ods (Weinstein and Capitanio, 2008). Briefly, when subjects were
approximately 1 year of age, we conducted 15 10-min continuous
focal observations on each subject over a 10-week period during
the mating season. Mating season in this population typically
lasts from August through December. Subjects consisted of two
birth cohorts, and were therefore observed in two separate years,
in 2003 and 2004. Subjects’ mean age at the start of behavioral
observations was 1.44 years. We observed subjects between 0800
and 1200 h, 4–5 days per week, and used a Psion Workabout
handheld computer equipped with The Observer Mobile 3.0
(Noldus Information Technology, Wageningen, The Netherlands)
to record frequencies and durations of proximity (within arm’s
reach of another monkey), play (shoving, grabbing, slapping,
chasing, pushing, wrestling and/or mouthing behavior accompa-
nied by a play face (wide eyes, open mouth without bared teeth)
or a loose, exaggerated posture and gait), nonaggressive physical
contact, and grooming (picking through and examining the fur
of another monkey, parting the fur with the hands or mouth).
We recorded identities of all participants as well as the direction
of initiation of all interactions. Inter-observer reliability exceeded
80% for all behaviors.
ASSESSMENT OF DOMINANCE RANKS
Dominance relations among corral group members were reg-
ularly assessed by behavioral management staff at the CNPRC
by observing the monkeys’ feeding order and direction of dis-
placements and aggression both around and in the absence of
temporarily concentrated food sources. Each corral contained a
clear-cut linear dominance hierarchy between the different matri-
lines, such that all members of the highest-ranking matriline were
dominant over all members of the second-ranking matriline, who
in turn outranked all members of the third-ranking matriline,
and so forth. We used the numerical dominance ranks derived by
the staff for each adult female at the time of yearling behavioral
data collection to classify matrilines as high-, middle-, or low-
ranking (i.e., top, middle, or bottom one-third of the hierarchy).
Since yearling rhesus macaques have not yet formalized their own
ranks in the hierarchy, we classified them according to maternal
rank.
BLOOD SAMPLING PROCEDURE
All available animals that had previously been subjects in the year-
ling affiliation study were sampled. We collected blood samples
from subjects on two occasions: the first sample was obtained
in October-November 2005 between 0115 h and 0230 h, and
the second sample in July-August 2006 between 1000 h and
1100 h. All animal handling and blood sampling procedures
were reviewed and approved by the Institutional Animal Care
and Use Committee of the University of California, Davis. At
the time the first sample was collected, 54 subjects were avail-
able for sampling: 48 subjects were still living in the outdoor
breeding corrals, five were pair-housed in standard indoor living
cages, and one was living in an outdoor corncrib. At the time
the second blood sample was collected, 51 subjects were avail-
able: 42 subjects were housed in the outdoor breeding corrals,
8 had been relocated indoors, and 1 subject continued to live
in a corncrib. Each outdoor-housed subject was net captured
and manually restrained in their corral or corncrib by trained
animal technicians, and a 1.0 ml sample of blood was drawn
via femoral venipuncture. Subjects were released back into their
corral or corncrib immediately following sample collection. A
maximum of 3 animals per corral were sampled per day in
a predetermined random order. Indoor-housed animals were
restrained by use of an intra-cage squeeze mechanism. After
collection, blood samples were transferred into sterile, vacuum-
sealed tubes coated with heparin, which were placed on ice until
being brought to the laboratory for storage and analysis. During
blood sampling, an observer used a stopwatch to record the
following time points: first entry into the outdoor cage or indoor
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 3
4. Weinstein et al. Rhesus macaque friendship and neuropeptides
room; if outdoors, the instant the animals was captured by the
net; if indoors, the moment at which the technician approached
the subject’s living cage; and the point at which the needle was
withdrawn.
ASSAYS
After blood samples were brought to the laboratory, they were
centrifuged at 4◦C for 10 min to separate and extract plasma.
Plasma was stored at −80◦C until assay. We measured plasma
concentrations of OT and AVP using a commercially prepared
enzyme immunoassay (EIA) kit manufactured by Assay Designs
(Ann Arbor, MI) and validated for use in rhesus macaques by
Bales et al. (2005). Prior to assay, plasma was diluted with assay
buffer using a 1:6 ratio for the OT assay, and a 1:8 ratio for the
AVP assay. Intra-assay coefficients of variation were 4.24% (OT)
and 5.16% (AVP), and the inter-assay coefficients of variation
were 3.71% for OT and 2.13% for AVP. Assay sensitivity was
15.55 pg/ml for OT and 2.34 pg/ml for AVP; none of the samples
fell below assay sensitivity.
STATISTICAL ANALYSIS
Quantifying friendships
We had previously calculated each subject’s friendships based
on durations of affiliative interactions with same-age peers (see
Weinstein and Capitanio, 2008). We divided each subject’s data
into five 2-week periods (biweeks); during each biweek we had
collected three 10-min focal samples per subject. We then cal-
culated the total duration of affiliation initiated by each subject
toward each peer during a given biweek as a percentage of total
time observed. We entered each of these percentages into separate
tables for each subject, with columns representing biweeks (N =
5), and rows representing all peer group-mates. Any peer(s) with
whom the focal animal did not affiliate during a given biweek
received a “0” cell value. For each biweek, we then calculated the
percentage of time the subject would have spent affiliating with
each peer if the interactions were distributed equally across all
peers during that time period, by summing the actual values in
each column (i.e., biweek) and dividing by the total number of
rows (peers) to give the expected value of that subject’s affiliation
with each peer. For example, if a subject with five peer group-
mates spent 10% of her time affiliating with those peers during
a given biweek, she would be expected to spend 2% of her time
with each peer if she were interacting randomly. We then used
a chi square test (df = 4) to compare the actual and expected
percentages for each individual peer across the 5 biweeks. Subject
X was considered to have initiated a friendship with animal Y for
behavior Z when X’s actual scores were significantly greater than
expected (p < 0.05). We calculated friendships for each affiliative
behavior separately, and classified them according to behavioral
content and quality, with reciprocal and multiplex friendships
representing the highest quality friendships (Table 1). Because
our subjects rarely, if ever, engaged in grooming and contact
with peers, we did not consider grooming or contact friendships
as standalone variables in our analyses, but we did factor them
into the calculations of multiplex, reciprocal, and total number of
friendships.
Relating friendships to neuropeptides
We used a repeated measures Linear Mixed Model analysis with
an unstructured repeated covariance type in IBM SPSS Statistics
version 21 to determine whether subjects’ friendships at age 1
(see Table 1) predicted plasma neuropeptide levels at two later
points in development. We also included maternal dominance
rank held at the time of behavioral data collection, sampling
time point, birth cohort, parturition status, housing condition
(living outdoors in a socially stable group, living outdoors in a
socially unstable group, or living indoors), and blood sampling
disturbance and draw times as independent variables. Blood sam-
pling disturbance time was the number of seconds that elapsed
between the time the door to the outdoor corral or indoor room
was opened and the time the needle was withdrawn. Draw time
was the number of seconds that elapsed between net capture
and needle withdrawal for outdoor animals, and the number of
seconds that elapsed between cage approach and needle with-
drawal for indoor animals. Because OT and AVP’s relation to
behavior has previously been found to differ according to sex
in a number of studies (e.g., Bales et al., 2004c, 2007a, 2013),
we computed the models separately for males and females. For
each sex, we began with a model that included all independent
variables, and used a backward elimination procedure to delete
variables with a p-value ≥ 0.10 until all non-significant variables
had been removed, aside from maternal dominance rank. Because
our previous analyses revealed that subjects’ friendships varied
significantly according to maternal dominance rank (Weinstein
and Capitanio, 2008), we left this variable in as a control in
our models. We then tested for interactions between maternal
dominance rank and all significant friendship variables that
remained in each model, and used backward elimination to
delete non-significant interactions. Finally, we assessed whether
friendship had a nonlinear relationship with neuropeptide lev-
els by testing the significance of the quadratic function of the
friendship variables that remained in each model. Table 2 lists
the number of subjects in each categorical independent variable
group.
Table 1 | Yearling friendship classification.
Proximity Friendship A preference displayed by the subject toward a peer for proximity
Play Friendship A preference displayed by the subject toward a peer for play
Multiplex Friendship* A preference displayed by the subject for a peer in more than one behavioral domain (e.g., subject preferred the peer for
both proximity and play)
Reciprocal Friendship* A preference displayed by the subject for a peer that also preferred that subject, regardless of behavioral domain
Total Number of Friends The total number of individually unique peers that were preferred by a subject, irrespective of behavioral domain
* Denotes higher quality friendships.
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 4
5. Weinstein et al. Rhesus macaque friendship and neuropeptides
RESULTS
OXYTOCIN MODEL–FEMALES
The final model for OT in females contained a number of signifi-
cant friendship variables. The relationship between the number of
reciprocal friendships and plasma OT was significantly described
by a U-shaped quadratic function (F(1,14) = 8.027, p = 0.013),
such that overall, females with low or high numbers of reciprocal
friendships had higher OT levels. Though rank by itself was not
significant (F(2,14) = 2.717, p = 0.101), there was a significant
interaction between rank and reciprocal friendships (F(2,14) =
10.083, p = 0.002; Figure 1), such that middle- and high-ranking
females with the fewest reciprocal friendships had high OT levels.
Additionally, high-ranking females who had the greatest numbers
of reciprocal friendships also had high OT levels. The number
of play friendships also significantly positively predicted plasma
OT (F(1,14) = 11.492, p = 0.004), and there was a significant
interaction between rank and the number of play friendships
(F(2,14) = 7.763, p = 0.005; Figure 2). As shown in Figure 2,
high-ranking females with no play friendships had the highest OT
levels, which decreased as the number of friendships increased.
Finally, cohort (the year that animals were born and therefore
represents age) was significant, with older females having higher
OT levels than younger females (F(1,14) = 19.669, p = 0.001;
Table 2 | Number of subjects in each categorical independent variable
group: sample 1 (sample 2).
Females Males
Total 25 (25) 29 (26)
Pregnant/Lactating 10 (10) N/A
Rank High 6 (6) 6 (6)
Middle 8 (8) 9 (9)
Low 11 (11) 14 (11)
Birth Cohort 2002 14 (14) 14 (12)
2003 11 (11) 15 (14)
Housing Condition Outdoor Stable 17 (17) 17 (16)
Outdoor Unstable 6 (7) 9 (3)
Indoors 2 (1) 3 (7)
FIGURE 1 | There was a significant interaction between rank and
reciprocal friendships (F(2,14) = 10.083, p = 0.002), such that middle- and
high-ranking females with the fewest reciprocal friendships had high
OT levels. Additionally, high-ranking females had the highest numbers of
reciprocal friendships, and they also had high OT levels.
Figure 3). We did not find sampling time point, parturition status,
housing condition, or blood sampling disturbance or draw times
to significantly predict later OT levels (all p > 0.1). Beta coeffi-
cients for independent variables reaching statistical significance
are in Table 3.
OXYTOCIN MODEL—MALES
Oxytocin was not related to friendship or any other independent
variable for males.
VASOPRESSIN MODEL—FEMALES
The final model for vasopressin in females contained two friend-
ship variables that neared significance: a positive trend for the
total number of friendships initiated by subjects (F(1,19) = 4.180,
p = 0.055; Figure 4, top panel), and a negative trend for the
total number of play friendships (F(1,19) = 4.021, p = 0.059;
Figure 4, bottom panel). Cohort was significant (F(1,19) = 5.173,
p = 0.035; Figure 3), with older females having higher AVP
concentrations than younger females, but rank was not (F(2,19) =
0.265, p = 0.770). We found neither sampling time point, parturi-
tion status, housing condition, nor blood sampling disturbance
FIGURE 2 | There was a significant interaction between rank and the
number of play friendships (F(2,14) = 7.763, p = 0.005), such that
high-ranking females with no play friendships had the highest OT
levels, which decreased as the number of friendships increased.
FIGURE 3 | We found significant birth cohort differences in OT for
females, with older females having higher OT levels than younger
females (F(1,14) = 19.669, p = 0.001). We also found significant birth cohort
differences in AVP for both females (F(1,19) = 5.173, p = 0.035) and males
(F(1,19.245) = 5.275, p = 0.033). In both sexes, older animals had higher AVP
concentrations than younger animals.
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 5
6. Weinstein et al. Rhesus macaque friendship and neuropeptides
Table 3 | Linear mixed model for females’ friendships and plasma
oxytocin concentrations.
Variable B Standard error
Birth cohort: 2002 348.37∗∗ 78.55
Birth cohort: 2003a – –
High Rank 128.81 155.83
Middle Ranka – –
Low Rank −193.62 113.34
Play Friendships 224.76∗∗ 41.45
Reciprocal Friendships −210.08∗ 80.77
Reciprocal Friendships2 −56.57∗ 19.97
High Rank × Play Friendships −157.08∗ 61.79
Middle Rank × Play Friendshipsa – –
Low Rank × Play Friendships −234.60∗∗ 61.95
High Rank × Reciprocal Friendships 314.44∗∗ 83.13
Middle Rank × Reciprocal Friendshipsa – –
Low Rank × Reciprocal Friendships 259.96∗∗ 67.05
a
Reference category; * p < 0.05; ** p < 0.01.
FIGURE 4 | Top panel: In females, the total number of friendships
initiated tended to positively predicted AVP levels (F(1,19) = 4.180, p =
0.055). Bottom panel: The total number of play friendships held by females
tended to negatively predict AVP levels (F(1,19) = 4.021, p = 0.059).
or draw times to significantly predict AVP levels (all p > 0.1).
Beta coefficients for significant and trend-level effects are in
Table 4.
Table 4 | Linear mixed model for females’ friendships and plasma
vasopressin concentrations.
Variable B Standard error
Birth cohort: 2002 161.17∗ 70.86
Birth cohort: 2003a – –
High Rank −55.76 88.75
Middle Ranka – –
Low Rank −41.11 66.48
Total Friendships 37.07b 18.13
Play Friendships −63.44b 31.64
a
Reference category; b
0.05 < p < 0.10; * p < 0.05.
FIGURE 5 | There was a significant interaction between rank and the
number of proximity friendships (F(2,18.857) = 6.279, p = 0.008), such
that middle-ranked males with only one proximity friendship had the
highest AVP levels.
VASOPRESSIN MODEL—MALES
The final model for vasopressin in males contained a number
of significant friendship variables, including a significant
positive association with the number of multiplex friendships
(F(1,22.166) = 7.140, p = 0.014) and significant negative
relationships with the number of proximity (F(1,22.319) =
7.361, p = 0.013) and play (F(1,20.138) = 4.337, p = 0.050)
friendships. We also found a positive association for subjects’
total number of friendships, which trended toward statistical
significance (F(1,20.802) = 3.370, p = 0.081). There was a
significant interaction between rank and the number of proximity
friendships (F(2,18.857) = 6.279, p = 0.008; Figure 5), such that
middle-ranked males with only one proximity friendship
had the highest AVP levels. Cohort (F(1,19.245) = 5.275,
p = 0.033; Figure 3) and rank (F(2,18.564) = 5.249,
p = 0.016) were also significant, with older males having
higher levels of AVP than younger males, and middle-ranked
males having the highest AVP. In addition to these variables,
measures associated with the blood draw procedures were
significant predictors of AVP concentrations: disturbance time
positively predicted AVP (F(1,27.991) = 28.188, p < 0.0001),
and draw time negatively predicted AVP (F(1,37.113) = 4.722,
p = 0.036). Neither sampling time point nor housing
condition significantly predicted AVP levels (all p > 0.1).
Beta coefficients for significant and trend-level associations are in
Table 5.
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 6
7. Weinstein et al. Rhesus macaque friendship and neuropeptides
Table 5 | Linear mixed model for males’ friendships and plasma
vasopressin concentrations.
Variable B Standard error
Birth cohort: 2002 117.61∗ 51.21
Birth cohort: 2003a – –
High Rank −283.55b 147.46
Middle Ranka – –
Low Rank −451.05∗∗ 139.74
Disturbance Time 0.30∗∗ 0.056
Draw Time −0.72∗ 0.33
Total Friendships 55.29b 30.12
Multiplex Friendships 132.30∗ 49.51
Play Friendships −91.21∗ 43.79
Proximity Friendships −202.80∗∗ 46.71
High Rank × Proximity Friendships 123.52∗ 44.33
Middle Rank × Proximity Friendshipsa – –
Low Rank × Proximity Friendships 170.83∗∗ 49.25
a
Reference category; b
0.05 < p < 0.10; * p ≤ 0.05; ** p < 0.01.
DISCUSSION
Our study revealed that the number and quality of friendships
experienced early in development by young rhesus monkeys
predict the future functioning of their OT and AVP systems.
These associations were complex, sex-specific, and often affected
by rank, especially in females. In interpreting our findings, we
note that our subjects’ friendship experiences were assessed at
1 year of age, which was 1–3 years prior to blood sampling.
Thus, developmental processes, including negative or positive
feedback on the OT and AVP systems, may have been reflected
in peptide levels at the time that the samples were taken (Bales
and Perkeybile, 2012).
Plasma OT was clearly more related to friendship in females
than in males, as no friendship measure significantly predicted
males’ OT concentrations. In females, OT concentrations were
related to both reciprocal and play friendships. As mentioned
in the Introduction section, reciprocity may be a key feature
of relationships that are subserved by the OT system (Atzil
et al., 2012; Schneiderman et al., 2012). In 3-year-old human
children, salivary OT levels are positively correlated with recip-
rocal interactions with a best friend (Feldman et al., 2013).
In adult human males, intranasal OT administration enhanced
caudate nucleus response to reciprocated cooperation, which
might indicate a more rewarding experience (Rilling et al., 2012).
Reciprocal friendships are particularly significant in young rhesus
monkeys, as they are among the highest quality friendships, and
are most likely to persist over time (Weinstein and Capitanio,
2012); similar results have been found in humans (Gershman
and Hayes, 1983; Bukowski et al., 1994). We found a quadratic,
U-shaped relationship between plasma OT and the number of
reciprocal friendships, which is in line with previous studies
demonstrating U-shaped associations between OT and social
behavior (e.g., Zhong et al., 2012), and suggests that opposing
phenotypes of friendship involvement can generate a similar
OT response. For females with very high numbers of reciprocal
friendships, greater OT concentrations are in keeping with the
abovementioned positive links between reciprocity and OT. The
elevated OT levels that characterized females with no or only
one reciprocal friendship, in contrast, is unclear; we speculate
this finding may reflect a compensatory response of the OT
system to a social stressor early in development (lack of high
quality friends). This is consistent with the finding that plasma
OT levels are higher in humans who experience gaps in their
social relationships (Taylor et al., 2006), and may reflect an
adaptive response which protects individuals from the deleterious
physiological and behavioral effects of social isolation (Grippo
et al., 2009). We also found an interaction between the number
of reciprocal friendships and rank (Figure 1). The highest OT
levels were displayed by middle-ranking females with no recip-
rocal friendships and high-ranking females with no or only one
reciprocal friendship, suggesting that to these females, a lack
of high quality friends may be a particularly powerful stressor.
Low-ranking females, on the other hand, might presumably have
lower expectations of receiving positive treatment from other
animals, and not respond as much to the lack of reciprocal
friendships. That dominance rank may influence an individ-
ual’s perceptions and expectations of her social environment
and subsequent OT functioning is consistent with studies in
humans showing OT’s relation to social behavior to be context-
dependent, varying according to whether an individual perceives
the social environment to be more or less safe (Olff et al.,
2013).
We found a significant positive main effect of number of
play friendships on OT concentrations in females, as well as a
significant interaction with dominance rank. Social play typically
requires an individual put him/herself in a vulnerable position,
and Spinka et al. (2001) proposed that the vulnerability and
loss of control inherent in play function to train individuals to
physically and emotionally cope with unexpected stressful situa-
tions. The overall positive effect of involvement in play friendships
on later OT concentrations supports this proposed function, as
OT has been previously shown to decrease subjective ratings of
stress (Heinrichs et al., 2003), possibly through its influence on
parasympathetic control (Norman et al., 2011) and/or amygdala
activity (Viviani et al., 2011). The relationship between OT, rank
and play friendships in females (Figure 2) suggests, however, that
only high-ranking females are especially sensitive to a lack of play
friendships (as well as a lack of reciprocal friendships, see above),
further supporting the idea that the greater OT concentrations
in these high-ranked females may be a compensatory, adaptive
response to a lack of social relationships which only emerges in
a specific context (that of occupying a position of elevated social
status).
In females, play friendships were also related to AVP levels,
showing an inverse association that trended toward but did not
reach significance (p = 0.059) (Figure 4, bottom panel; although
graphically this appears to be another U-shaped relationship, the
quadratic function was not significant). The same negative beta
coefficient characterizing the relationship of AVP to number of
play friendships in females was also evident in males, where it
achieved significance. AVP is associated with many peripheral
functions including water retention, increasing vascular con-
striction, physical activity (see below), and increasing HPA axis
activity by potentiating the stimulatory effect of corticotropin-
releasing hormone (CRH) on the secretion of adrenocorticotropic
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 7
8. Weinstein et al. Rhesus macaque friendship and neuropeptides
hormone (ACTH) from the anterior pituitary (Aguilera, 2011).
Over the course of development, a greater number of play friend-
ships might have led to lower levels of AVP through the stress-
reducing effects of play. The fact that this association between
play friendships and AVP achieved statistical significance only
in males, however, suggests that play’s stress-relieving effects
may be more potent in male than in female rhesus macaques,
who spend less time playing overall (Weinstein and Capitanio,
2008). Only a small handful of studies—primarily limited to
rodents—have specifically investigated AVP’s relation to play
(Cheng et al., 2008; Cheng and Delville, 2009; Veenema and
Neumann, 2009; Wang et al., 2012), and the mechanisms by
which play may regulate and be regulated by the AVP sys-
tem are therefore not fully understood, and warrant further
investigation.
In males, higher plasma AVP was significantly associated with
a greater number of multiplex friendships, which are charac-
terized by a preference displayed toward a peer for more than
one type of social interaction. AVP has been associated in many
social contexts with a willingness to engage proactively (Carter
et al., 1995; Bosch and Neumann, 2012), and in some contexts
and dosages it is anxiolytic (Dharmadhikari et al., 1997). It is
therefore not surprising to see it associated with higher numbers
of multiplex friendships, in that more proactive animals might
be likelier to initiate consistent social interactions with a greater
number of peers in a variety of behavioral domains. High plasma
AVP also tended to be positively predicted by the total number of
friends in both females (Figure 4, top panel) and males, though
the associations were not statistically significant (p = 0.055 for
females and p = 0.081 for males). Although these trends support
the aforementioned notion that high AVP may relate to a more
socially proactive phenotype, their failure to reach significance
suggests that the total number of an individual’s friends may
not be the most relevant factor to neuropeptide functioning,
and that—at least for males—it is involvement in behaviorally
complex (i.e., high quality) friendships that plays a key role in the
development of the AVP system.
In males, but not females, AVP levels were significantly pre-
dicted by involvement in proximity friendships, suggesting dif-
ferential importance of proximity friendships by sex. Proximity
friendships are characterized by spending significant amounts of
time together in a relatively sedentary state. Males with more
proximity friendships had decreased AVP levels, consistent with
this neuropeptide’s expected inverse relationship with physical
inactivity. The relationship between rank, proximity friendships,
and AVP was complicated, with middle-ranking animals who had
only one proximity friendship—the lowest number of proximity
friendships held by any animal—showing especially high levels
of AVP (Figure 5). Middle-ranked monkeys hold a unique status
in their social groups, as they are dominant and subordinate
to approximately the same number of their group-mates, and
consequently must be equally prepared to exhibit either one of
two opposing responses to a conspecific (dominance or submis-
sion). Middle-ranked individuals are more attentive to a variety
of social situations as compared to their high- and low-ranking
counterparts (Haude et al., 1976; Capitanio et al., 1985), and
heightened social attention may be necessary for such behavioral
flexibility. As social attention and perception may relate to AVP
functioning (Thompson et al., 2004, 2006), we speculate that
in our male subjects, the high attentional demands of being
middle-ranked are reflected by high AVP concentrations (recall
that middle-ranked males had higher AVP overall), which may
decrease as a result of the buffering effects of having more
proximity friends. The manifold associations between different
friendship types and plasma AVP in males suggests that in rhesus
macaques, as in humans, AVP’s role in social relationships reflects
diverse social processes (Gouin et al., 2012), which may also be
influenced by an individual’s social environment (i.e., dominance
rank).
In males, disturbance time positively related to plasma levels
of AVP, while draw time was negatively related. The positive asso-
ciation between disturbance time (the time that elapsed between
the opening of the door to animals’ enclosure and the time the
needle was withdrawn) and AVP suggests that AVP was secreted
in response to physical activity and/or the stress of the capture
procedure in males. At the CNPRC, net capturing a single monkey
causes all of the monkeys in a particular corral to run several
laps around its periphery. Previous studies in both humans and
animals have found that plasma AVP levels show an immediate
surge in response to exercise (Alexander et al., 1991), and the
degree to which AVP levels rise is determined by exercise intensity
(Convertino et al., 1981; el-Sayed et al., 1990) and duration
(Coiro et al., 2010; Reza et al., 2011). AVP secretion following the
experience of running and net capture may in turn stimulate the
release of ACTH, thus activating the HPA axis (Aguilera, 2011).
Conversely, draw time reflects the amount of time our subjects
spent being restrained for the blood draw, and therefore physically
inactive, and the inverse relationship between draw time and AVP
suggests that AVP levels began to drop as soon as the animal
was captured. Similarly, in humans, AVP levels begin to drop
almost immediately upon exercise cessation (Ferrari et al., 1991;
Wittert et al., 1991). To our knowledge, ours is the first study to
demonstrate a relationship between physical activity and AVP in
nonhuman primates, though we found this effect only in males.
This sex-specific effect may reflect the life-history difference that
while females remain in their natal group their entire lives, males
emigrate from their troop upon reaching puberty, and wander
until they find a new troop to join (Lindburg, 1971). AVP may
thus be an important mechanism involved in the regulation of
male emigration; consistent with this interpretation is the fact that
our male subjects were approaching or had already reached ado-
lescence, and nearly ready to commence emigrating had they been
living in the wild. Our results therefore indicate that measures of
physical activity may be important to include in any future studies
of AVP and social relationships.
We also found a relationship between birth cohort and both
OT and AVP, with AVP higher in both older males and older
females, and OT higher in older females (Figure 3). Note, how-
ever, that we did not find significant differences in either OT or
AVP between the first and second blood sampling time points,
suggesting that neither OT nor AVP concentrations show seasonal
variation in this species, and that any developmental changes
in our subjects that occurred between these two time points
were not substantial enough to significantly alter neuropeptide
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 8
9. Weinstein et al. Rhesus macaque friendship and neuropeptides
concentrations. Our first blood sample was taken from 2.5 and
3.5 year olds, thus the 2.5 year olds were pre-pubescent while the
3.5 year olds were peri/post-pubescent (and some females were
mature enough to be in the very early stages of pregnancy). These
two cohorts thus represent a contrast between juvenility-early
adolescence and adolescence-early adulthood. There is only lim-
ited evidence for changes in plasma OT levels with aging (Ebner
et al., 2013), however, since OT levels are estrogen-dependent
(Amico et al., 1981), a rise might be expected with reproductive
maturation in females. Similarly, higher AVP levels in the older
cohort may be associated with maturation of the reproductive
axis; AVP is androgen-dependent (De Vries and Villalba, 1997),
and testosterone would likely be higher in peri/post-pubescent
than in pre-pubescent males (Bernstein et al., 1991). We note that
at both blood sampling time points, pregnancy/having an infant
had no effect on either neuropeptide.
Friendships are especially important to study in some special
populations such as children with autism (Rowley et al., 2012).
Children with autism display fewer reciprocal friendships (Kasari
et al., 2011), and these lower quality friendships in some cases
caused even higher anxiety than a lack of friends (Mazurek and
Kanne, 2010). Play dates can be beneficial to social functioning
in children with autism (Frankel et al., 2011), especially with
parent-assisted supervision (Frankel and Whitham, 2011). Given
both the large number of associations between OT, AVP, and
autism (Carter, 2007; Jacob et al., 2007; Gregory et al., 2009, 2013;
Feldman, 2012), and the current initiatives to use intranasal OT as
a therapeutic for autism (Anagnoustou et al., 2012; Bakermans-
Kranenburg and Van Ijzendoorn, 2013), it will be important for
future studies to consider friendships and how these treatments
affect the quality of this very salient real-life measure of function-
ing in children with autism.
Overall, we found OT and AVP to relate to friendship in
very sex-specific ways. Sex differences in friendship involvement
have been well documented in children (Kon and Losenkov,
1978; Benenson et al., 1998; Hardy et al., 2002; Benenson and
Christakos, 2003; Benenson and Alavi, 2004; de Guzman et al.,
2004), and have been similarly demonstrated in rhesus macaques
(Weinstein and Capitanio, 2008, 2012). The examination of the
sex-specific ways in which OT and AVP relate to social relation-
ships in nonhuman primates has thus far been rarely studied,
but may be particularly important because of potential transla-
tional relevance. While autism is primarily a condition found in
males (CDC, 2012), 1 in 252 American girls are also affected.
So far, clinical trials with OT have been carried out mainly in
males (Tachibana et al., 2013; Dadds et al., 2014), or in samples
with insufficient numbers of females to detect sex differences in
treatment efficacy (Anagnoustou et al., 2012). Plasma OT and
AVP show sex-specific relationships to autism symptoms (Miller
et al., 2013). Social context is also potentially important to the
actions of OT (Bartz et al., 2011), suggesting that sex differences
in friendships could interact with sex differences in reactions to
therapeutic OT.
It is important to note that although we found several sig-
nificant associations between early friendship involvement and
later neuropeptide concentrations, it is impossible to determine
the precise causal relationships between these variables. Given
that our friendship measures preceded blood sampling by 1 or
more years, we believe it likely that early friendship involvement
produced lasting effects on neuropeptide functioning. However,
as mentioned in the Introduction section, it is certainly possi-
ble for early neuropeptide functioning to influence an individ-
ual’s propensity to form friendships as well (e.g., Bales et al.,
2007b). Previous research suggests that peripheral neuropeptide
concentrations reflect both trait-level characteristics (i.e., per-
sonality or temperament) and state-level factors (i.e., aspects of
an individual’s social environment and interactions; Strathearn
et al., 2012), thus the peripheral concentrations in our subjects
could have similarly been a product not only of the state-level
variables of friendship involvement, but of trait-level variables
such as temperament, which our earlier studies have shown to
influence rhesus macaque friendships (Weinstein and Capitanio,
2008, 2012). Examining the relationship between temperament
and neuropeptide concentrations in this species is a direction that
we are currently pursuing.
Finally, there is a gap in the literature on neuropeptides and
social relationships with regard to friendships. This represents
a future direction that should be explored, for several reasons.
First of all, friendships are distinct from attachment relation-
ships (Mason and Mendoza, 1998), but how the physiological
substrates differ is not known. Friendships are important for
children’s healthy development, both neurotypical and those with
developmental disorders. Friendships may be more pervasive than
attachment relationships, and are very important in predicting
long-term health outcomes, which particularly calls for further
investigation of the role of OT in social buffering. Lastly, in a
recent review of sociality and neuropeptides, Goodson (2013)
points out that sociality is a multifaceted phenomenon which
is often mistakenly considered homogeneous and therefore not
parsed into its various components when examining the under-
lying roles of OT and AVP. Specifically teasing apart the roles
played by OT and AVP not only in the general phenomenon of
friendship, but in specific types of friendships that vary in quality,
is therefore critical in order to understand how neuropeptides
relate to each of the wide-ranging aspects of sociality that evolved
in both human and animal species.
AUTHOR CONTRIBUTIONS
Tamara A. R. Weinstein, John P. Capitanio, and Karen L. Bales
designed the study and analyzed the data. Tamara A. R. Weinstein
conducted the research with critical assistance from Nicole
Maninger and Caroline M. Hostetler. The manuscript was written
by Tamara A. R. Weinstein and Karen L. Bales, and edited by
all authors. John P. Capitanio and Karen L. Bales supervised the
project.
ACKNOWLEDGMENTS
We are very grateful to Laura Del Rosso, Erna Tarara, Isabel
Shelton-Mottsmith, Christine Brennan, Katie Hinde, and Susie
Kang for assisting with data collection, and to the CNPRC animal
care staff for their help with blood sampling, animal identifica-
tion, and accommodating our research schedule. This work was
supported by NIH grant RR00169 to the CNPRC and NIH grant
RR019970 to John P. Capitanio. While conducting this research,
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 9
10. Weinstein et al. Rhesus macaque friendship and neuropeptides
Tamara A. R. Weinstein was supported by the NSF Graduate
Research Fellowship and by the NIH training grant MH20006.
During the writing of this paper, Karen L. Bales was funded by
NIH grants HD053555 and HD071998, and the Good Nature
Institute.
REFERENCES
Aguilera, G. (2011). HPA axis responsiveness to stress: implications for healthy
aging. Exp. Gerontol. 46, 90–95. doi: 10.1016/j.exger.2010.08.023
Alexander, S. L., Irvine, C. H. G., Ellis, M. J., and Donald, R. A. (1991). The effect
of acute exercise on the secretion of corticotropin-releasing factor, arginine
vasopressin and adrenocorticotropin as measured in pituitary venous-blood
from the horse. Endocrinology 128, 65–72. doi: 10.1210/endo-128-1-65
Amico, J. A., Seif, S. M., and Robinson, A. G. (1981). Oxytocin in human plasma:
correlation with neurophysin and stimulation with estrogen. J. Clin. Endocrinol.
Metab. 52, 988–993. doi: 10.1210/jcem-52-5-988
Anagnoustou, E., Soorya, L., Chaplin, W., Bartz, J., Halpern, D., Wasserman, S.,
et al. (2012). Intranasal oxytocin versus placebo in the treatment of adults with
autism spectrum disorders: a randomized controlled trial. Mol. Autism 3:16.
doi: 10.1186/2040-2392-3-16
Atzil, S., Hendler, T., Zagoory-Sharon, O., Winetraub, Y., and Feldman, R. (2012).
Synchrony and specificity in the maternal and paternal brain: relations to
oxytocin and vasopressin. J. Am. Acad. Child Adolesc. Psychiatry 51, 798–811.
doi: 10.1016/j.jaac.2012.06.008
Bagwell, C. L., Newcomb, A. F., and Bukowski, W. M. (1998). Preadolescent
friendship and peer rejection as predictors of adult adjustment. Child Dev. 69,
140–153. doi: 10.2307/1132076
Bakermans-Kranenburg, M. J., and Van Ijzendoorn, M. H. (2013). Sniffing around
oxytocin: review and meta-analyses of trials in healthy and clinical groups with
implications for pharmacotherapy. Transl. Psychiatry 3:e258. doi: 10.1038/tp.
2013.34
Bales, K. L., Abdelnabi, M., Cushing, B. S., Ottinger, M. A., and Carter, C. S.
(2004a). Effects of neonatal oxytocin manipulations on male reproductive
potential in prairie voles. Physiol. Behav. 81, 519–526. doi: 10.1016/j.physbeh.
2004.02.016
Bales, K. L., and Carter, C. S. (2003a). Developmental exposure to oxytocin
facilitates partner preferences in male prairie voles (Microtus ochrogaster). Behav.
Neurosci. 117, 854–859. doi: 10.1037/0735-7044.117.4.854
Bales, K. L., and Carter, C. S. (2003b). Sex differences and developmental effects
of oxytocin on aggression and social behavior in prairie voles (Microtus ochro-
gaster). Horm. Behav. 44, 178–184. doi: 10.1016/S0018-506X(03)00154-5
Bales, K. L., Kim, A. J., Lewis-Reese, A. D., and Carter, C. S. (2004b). Both
oxytocin and vasopressin may influence alloparental behavior in male prairie
voles. Horm. Behav. 45, 354–361. doi: 10.1016/j.yhbeh.2004.01.004
Bales, K. L., Kramer, K. M., Hostetler, C. M., Capitanio, J. P., and Mendoza, S. P.
(2005). Validation of oxytocin and vasopressin blood assay for primates: what
can blood tell us? Am. J. Primatol. 66, 73–73.
Bales, K. L., and Perkeybile, A. M. (2012). Developmental experiences and the
oxytocin receptor system. Horm. Behav. 61, 313–319. doi: 10.1016/j.yhbeh.2011.
12.013
Bales, K. L., Perkeybile, A. M., Conley, O. G., Lee, M. H., Guoynes, C. D., Downing,
G. M., et al. (2013). Chronic intranasal oxytocin causes long-term impairment
in partner preference formation in male prairie voles. Biol. Psychiatry 74, 180–
188. doi: 10.1016/j.biopsych.2012.08.025
Bales, K. L., Pfeifer, L. A., and Carter, C. S. (2004c). Sex differences and effects of
manipulations of oxytocin on alloparenting and anxiety in prairie voles. Dev.
Psychobiol. 44, 123–131. doi: 10.1002/dev.10165
Bales, K. L., Plotsky, P. M., Young, L. J., Lim, M. M., Grotte, N. D., Ferrer, E.,
et al. (2007a). Neonatal oxytocin manipulations have long-lasting, sexually
dimorphic effects on vasopressin receptors. Neuroscience 144, 38–45. doi: 10.
1016/j.neuroscience.2006.09.009
Bales, K. L., van Westerhuyzen, J. A., Lewis-Reese, A. D., Grotte, N. D., Lanter, J. A.,
and Carter, C. S. (2007b). Oxytocin has dose-dependent developmental effects
on pair-bonding and alloparental care in female prairie voles. Horm. Behav. 52,
274–279. doi: 10.1016/j.yhbeh.2007.05.004
Bartz, J. A., Zaki, J., Bolger, N., and Ochsner, K. N. (2011). Social effects of oxytocin
in humans: context and person matter. Trends Cogn. Sci. 15, 301–309. doi: 10.
1016/j.tics.2011.05.002
Bartz, J. A., Zaki, J., Ochsner, K. N., Bolger, N., Kolevzon, A., Ludwig, N., et al.
(2010). Effects of oxytocin on recollections of maternal care and closeness. Proc.
Natl. Acad. Sci. U S A 107, 21371–21375. doi: 10.1073/pnas.1012669107
Baumgartner, T., Heinrichs, M., Vonlanthen, A., Fischbacher, U., and Fehr, E.
(2008). Oxytocin shapes the neural circuitry of trust and trust adaptation in
humans. Neuron 58, 639–650. doi: 10.1016/j.neuron.2008.04.009
Beehner, J. C., Bergman, T. J., Cheney, D. L., Seyfarth, R. M., and Whitten, P. L.
(2005). The effect of new alpha males on female stress in free-ranging baboons.
Anim. Behav. 69, 1211–1221. doi: 10.1016/j.anbehav.2004.08.014
Benenson, J. F., and Alavi, K. (2004). Sex differences in children’s investment in
same-sex peers. Evol. Hum. Behav. 25, 258–266. doi: 10.1016/j.evolhumbehav.
2004.05.002
Benenson, J. F., and Christakos, A. (2003). The greater fragility of females’ ver-
sus males’ closest same-sex friendships. Child Dev. 74, 1123–1129. doi: 10.
1111/1467-8624.00596
Benenson, J. F., Morganstein, T., and Roy, R. (1998). Sex differences in children’s
investment in peers. Hum. Nature Interdiscip. Biosoc. Perspect. 9, 369–390.
Bernstein, I. S., Ruehlmann, T. E., Judge, P. G., Lindquist, T., and Weed, J. L. (1991).
Testosterone changes during the period of adolescence in male rhesus-monkeys
(Macaca mulatta). Am. J. Primatol. 24, 29–38.
Boccia, M. L., Scanlan, J. M., Laudenslager, M. L., Berger, C. L., Hijazi, A. H.,
and Reite, M. L. (1997). Juvenile friends, behavior and immune responses to
separation in bonnet macaque infants. Physiol. Behav. 61, 191–198. doi: 10.
1016/s0031-9384(96)00370-8
Bosch, O. J., and Neumann, I. D. (2012). Both oxytocin and vasopressin are
mediators of maternal care and aggression in rodents: from central release
to sites of action. Horm. Behav. 61, 293–303. doi: 10.1016/j.yhbeh.2011.
11.002
Buchheim, A., Heinrichs, M., George, C., Pokorny, D., Koops, E., Henningsen,
P., et al. (2009). Oxytocin enhances the experience of attachment secu-
rity. Psychoneuroendocrinology 34, 1417–1422. doi: 10.1016/j.psyneuen.2009.
04.002
Bukowski, W. M., Hoza, B., and Boivin, M. (1994). Measuring friendship quality
during pre-adolescence and early adolescence—the development and psycho-
metric properties of the friendship qualities scale. J. Soc. Pers. Relatsh. 11, 471–
484. doi: 10.1177/0265407594113011
Capitanio, J. P., Boccia, M. L., and Colaiannia, D. J. (1985). The influence of rank on
affect perception by pigtailed macaques (Macaca-Nemestrina). Am. J. Primatol.
8, 53–59. doi: 10.1002/ajp.1350080106
Capitanio, J. P., and Emborg, M. E. (2008). Contributions of non-human pri-
mates to neuroscience research. Lancet 371, 1126–1135. doi: 10.1016/S0140-
6736(08)60489-4
Carter, C. S. (2003). Developmental consequences of oxytocin. Physiol. Behav. 79,
383–397. doi: 10.1016/s0031-9384(03)00151-3
Carter, C. S. (2007). Sex differences in oxytocin and vasopressin: implications for
autism spectrum disorders? Behav. Brain Res. 176, 170–186. doi: 10.1016/j.bbr.
2006.08.025
Carter, C. S., DeVries, A. C., and Getz, L. L. (1995). Physiological substrates of
mammalian monogamy: the prairie vole model. Neurosci. Biobehav. Rev. 19,
303–314. doi: 10.1016/0149-7634(94)00070-h
CDC. (2012). Prevalence of autism spectrum disorders: autism and developmental
disabilities monitoring network, 14 sites, United States, 2008. MMWR Surveill.
Summ. 61, 1–19.
Cheng, S. Y., and Delville, Y. (2009). Vasopressin facilitates play fighting in juvenile
golden hamsters. Physiol. Behav. 98, 242–246. doi: 10.1016/j.physbeh.2009.
04.019
Cheng, S. Y., Taravosh-Lahn, K., and Delville, Y. (2008). Neural circuitry of
play fighting in golden hamsters. Neuroscience 156, 247–256. doi: 10.1016/j.
neuroscience.2008.07.048
Cho, M. M., Devries, A. C., Williams, J. R., and Carter, C. S. (1999). The effects of
oxytocin and vasopressin on partner preferences in male and female prairie voles
(Microtus ochrogaster). Behav. Neurosci. 113, 1071–1079. doi: 10.1037/0735-
7044.113.5.1071
Cohen, S., and Wills, T. A. (1985). Stress, social support and the buffering hypoth-
esis. Psychol. Bull. 98, 310–357. doi: 10.1037//0033-2909.98.2.310
Coiro, V., Volpi, R., Maffei, M. L., Volta, E., Melani, A., and Chiodera, P. (2010).
Effect of naloxone on the inhibitory effect of melatonin on the release of
arginine-vasopressin induced by physical exercise in man. Regul. Pept. 162, 1–
4. doi: 10.1016/j.regpep.2010.03.007
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 10
11. Weinstein et al. Rhesus macaque friendship and neuropeptides
Convertino, V. A., Keil, L. C., Bernauer, E. M., and Greenleaf, J. E. (1981). Plasma
volume, osmolality, vasopressin and renin activity during graded exercise in
man. J. Appl. Physiol. Respir. Environ. Exerc. Physiol. 50, 123–128.
Crockford, C., Wittig, R. M., Langergraber, K., Ziegler, T. E., Zuberbuhler, K.,
and Deschner, T. (2013). Urinary oxytocin and social bonding in related and
unrelated wild chimpanzees. Proc. Biol. Sci. 280:20122765. doi: 10.1098/rspb.
2012.2765
Crockford, C., Wittig, R. M., Whitten, P. L., Seyfarth, R. A., and Cheney, D. L.
(2008). Social stressors and coping mechanisms in wild female baboons (Papio
hamadryas ursinus). Horm. Behav. 53, 254–265. doi: 10.1016/j.yhbeh.2007.
10.007
Cushing, B. S., Okorie, U., and Young, L. J. (2003). The effects of neonatal castration
on the subsequent behavioural response to centrally administered arginine
vasopressin and the expression of V-1a receptors in adult male prairie voles. J.
Neuroendocrinol. 15, 1021–1026. doi: 10.1046/j.1365-2826.2003.01097.x
Dadds, M. R., Macdonald, E., Cauchi, A., Williams, K., Levy, F., and Brennan, J.
(2014). Nasal oxytocin for social deficits in childhood autism: a randomized
controlled trial. J. Autism Dev. Disord. 44, 521–531. doi: 10.1007/s10803-013-
1899-3
Datta, S. (1988). The acquisition of dominance among free-ranging rhesus
monkey siblings. Anim. Behav. 36, 754–772. doi: 10.1016/s0003-3472(88)
80159-3
de Guzman, M. R. T., Carlo, G., Ontai, L. L., Koller, S. H., and Knight, G. P. (2004).
Gender and age differences in Brazilian children’s friendship nominations and
peer sociometric ratings. Sex Roles 51, 217–225. doi: 10.1023/b:sers.0000037765.
77313.c4
De Vries, G. J., and Villalba, C. (1997). Brain sexual dimorphism and sex differences
in parental and other social behaviors. Ann. N Y Acad. Sci. 807, 273–286. doi: 10.
1111/j.1749-6632.1997.tb51926.x
de Waal, F. B. M., and Luttrell, L. M. (1985). The formal hierarchy of rhesus
macaques—an investigation of the bared-teeth display. Am. J. Primatol. 9, 73–
85. doi: 10.1002/ajp.1350090202
Dharmadhikari, A., Lee, Y. S., Roberts, R. L., and Carter, C. S. (1997). Exploratory
behavior correlates with social organization and is responsive to peptide injec-
tions in prairie voles. Ann. N Y Acad. Sci. 807, 610–612. doi: 10.1111/j.1749-
6632.1997.tb51982.x
Ebner, N. C., Maura, G. M., Macdonald, K., Westberg, L., and Fischer, H. (2013).
Oxytocin and socioemotional aging: current knowledge and future trends.
Front. Hum. Neurosci. 7:487. doi: 10.3389/fnhum.2013.00487
el-Sayed, M. S., Davies, B., and Morgan, D. B. (1990). Vasopressin and plasma
volume response to submaximal and maximal exercise in man. J. Sports Med.
Phys. Fitness 30, 420–425.
Erath, S. A., Flanagan, K. S., Bierman, K. L., and Tu, K. M. (2010). Friendships
moderate psychosocial maladjustment in socially anxious early adolescents. J.
Appl. Dev. Psychol. 31, 15–26. doi: 10.1016/j.appdev.2009.05.005
Feldman, R. (2012). Oxytocin and social affiliation in humans. Horm. Behav. 61,
380–391. doi: 10.1016/j.yhbeh.2012.01.008
Feldman, R., Gordon, I., Influs, M., Gutbir, T., and Ebstein, R. P. (2013). Parental
oxytocin and early caregiving jointly shape children’s oxytocin response and
social reciprocity. Neuropsychopharmacology 38, 1154–1162. doi: 10.1038/npp.
2013.22
Feldman, R., Gordon, I., Schneiderman, I., Weisman, O., and Zagoory-Sharon, O.
(2010a). Natural variations in maternal and paternal care are associated with
systematic changes in oxytocin following parent-infant contact. Psychoneuroen-
docrinology 35, 1133–1141. doi: 10.1016/j.psyneuen.2010.01.013
Feldman, R., Gordon, I., and Zagoory-Sharon, O. (2010b). The cross-generation
transmission of oxytocin in humans. Horm. Behav. 58, 669–676. doi: 10.1016/j.
yhbeh.2010.06.005
Ferrari, R., Ceconi, C., Rodella, A., DeGiuli, F., Panzali, A., and Harris, P. (1991).
Temporal relations of the endocrine response to exercise. Cardioscience 2, 131–
139.
Frankel, F. D., Goropse, C. M., Chang, Y. C., and Sugar, C. A. (2011). Mothers’
reports of play dates and observation of school playground behavior of children
having high-functioning autism spectrum disorders. J. Child Psychol. Psychiatry
52, 571–579. doi: 10.1111/j.1469-7610.2010.02318.x
Frankel, F. D., and Whitham, C. (2011). Parent-assisted group treatment for
friendship problems of children with autism spectrum disorders. Brain Res.
1380, 240–245. doi: 10.1016/j.brainres.2010.09.047
Fullerton, C. S., and Ursano, R. J. (1994). Preadolescent peer friendships—a critical
contribution to adult social relatedness. J. Youth Adolesc. 23, 43–63. doi: 10.
1007/bf01537141
Gershman, E. S., and Hayes, D. S. (1983). Differential stability of reciprocal friend-
ships and unilateral relationships among preschool-children. Merrill Palmer Q.
J. Dev. Psychol. 29, 169–177.
Gimpl, G., and Fahrenholz, F. (2001). The oxytocin receptor system: structure,
function and regulation. Physiol. Rev. 81, 629–683.
Goodson, J. L. (2013). Deconstructing sociality, social evolution and relevant
nonapeptide functions. Psychoneuroendocrinology 38, 465–478. doi: 10.1016/j.
psyneuen.2012.12.005
Gordon, I., Zagoory-Sharon, O., Schneiderman, I., Leckman, J. F., Weller, A., and
Feldman, R. (2008). Oxytocin and cortisol in romantically unattached young
adults: associations with bonding and psychological distress. Psychophysiology
45, 349–352. doi: 10.1111/j.1469-8986.2008.00649.x
Gouin, J. P., Carter, C. S., Pournajafi-Nazarloo, H., Malarkey, W. B., Loving, T. J.,
Stowell, J., et al. (2012). Plasma vasopressin and interpersonal functioning. Biol.
Psychol. 91, 270–274. doi: 10.1016/j.biopsycho.2012.07.003
Green, L. A., Fein, D., Modahl, C., Feinstein, C., Waterhouse, L., and Morris,
M. (2001). Oxytocin and autistic disorder: alterations in peptide forms. Biol.
Psychiatry 50, 609–613. doi: 10.1016/s0006-3223(01)01139-8
Gregory, S. G., Anthopolos, R., Osgood, C. E., Grotegut, C. A., and Miranda,
M. L. (2013). Association of autism with induced or augmented childbirth in
North Carolina birth record (1990–1998) and education research (1997–2007)
databases. JAMA Pediatr. 167, 959–966. doi: 10.1001/jamapediatrics.2013.2904
Gregory, S. G., Connelly, J. J., Towers, A. J., Johnson, J., Biscocho, D., Marcunas,
C. A., et al. (2009). Genomic and epigenetic evidence for oxytocin receptor
deficiency in autism. BMC Med. 7:62. doi: 10.1186/1741-7015-7-62
Grippo, A. J., Trahanas, D. M., Zimmerman, R. R., Porges, S. W., and Carter,
C. S. (2009). Oxytocin protects against negative behavioral and autonomic
consequences of long-term social isolation. Psychoneuroendocrinology 34, 1542–
1553. doi: 10.1016/j.psyneuen.2009.05.017
Guastella, A. J., Kenyon, A. R., Alvares, G. A., Carson, D. S., and Hickie, I. B. (2010).
Intranasal arginine vasopressin enhances the encoding of happy and angry
faces in humans. Biol. Psychiatry 67, 1220–1222. doi: 10.1016/j.biopsych.2010.
03.014
Gust, D. A., Gordon, T. P., Brodie, A. R., and McClure, H. M. (1994). Effect of
a preferred companion in modulating stress in adult female rhesus monkeys.
Physiol. Behav. 55, 681–684. doi: 10.1016/0031-9384(94)90044-2
Hardy, C. L., Bukowski, W. M., and Sippola, L. K. (2002). Stability and change in
peer relationships during the transition to middle-level school. J. Early Adolesc.
22, 117–142. doi: 10.1177/0272431602022002001
Haude, R. H., Graber, J. G., and Farres, A. G. (1976). Visual observing by rhesus
monkeys some relationships with social dominance rank. Anim. Learn. Behav.
4, 163–166. doi: 10.3758/bf03214028
Heinrichs, M., Baumgartner, T., Kirschbaum, C., and Ehlert, U. (2003). Social
support and oxytocin interact to suppress cortisol and subjective responses
to psychosocial stress. Biol. Psychiatry 54, 1389–1398. doi: 10.1016/s0006-
3223(03)00465-7
Higley, J. D., Hopkins, W. D., Thompson, W. W., Byrne, E. A., Hirsh, R. M., and
Suomi, S. J. (1992). Peers as primary attachment sources in yearling rhesus
monkeys (Macaca mulatta). Dev. Psychol. 28, 1163–1171. doi: 10.1037/0012-
1649.28.6.1163
Hinde, R. A., and Spencer-Booth, Y. (1967). The behaviour of socially living rhesus
monkeys in their first two and a half years. Anim. Behav. 15, 169–196. doi: 10.
1016/s0003-3472(67)80029-0
House, J. S., Landis, K. R., and Umberson, D. (1988). Social relationships and
health. Science 241, 540–545. doi: 10.1126/science.3399889
Jacob, S., Brune, C. W., Carter, C. S., Leventhal, B. L., Lord, C., Cook, E. H. Jr., et al.
(2007). Association of the oxytocin receptor gene (OXTR) in Caucasian children
and adolescents with autism. Neurosci. Lett. 417, 6–9. doi: 10.1016/j.neulet.2007.
02.001
Jarcho, M. R., Mendoza, S. P., Mason, W. A., Yang, X., and Bales, K. L. (2011).
Intranasal vasopressin affects pair bonding and peripheral gene expression in
male Callicebus cupreus. Genes Brain Behav. 10, 375–383. doi: 10.1111/j.1601-
183x.2010.00677.x
Joffe, T. H. (1997). Social pressures have selected for an extended juvenile period in
primates. J. Hum. Evol. 32, 593–605. doi: 10.1006/jhev.1997.0140
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 11
12. Weinstein et al. Rhesus macaque friendship and neuropeptides
Kagerbauer, S. M., Martin, J., Schuster, T., Blobner, M., Kochs, E. F., and Land-
graf, R. (2013). Plasma oxytocin and vasopressin do not predict neuropeptide
concentrations in human cerebrospinal fluid. J. Neuroendocrinol. 25, 668–673.
doi: 10.1111/jne.12038
Kasari, C., Locke, J., Gulsrud, A., and Rotheram-Fuller, E. (2011). Social networks
and friendships at school: comparing children with and without ASD. J. Autism
Dev. Disord. 41, 533–544. doi: 10.1007/s10803-010-1076-x
Kenkel, W. M., Paredes, J., Yee, J. R., Pournajafi-Nazarloo, H., Bales, K. L., and
Carter, C. S. (2012). Neuroendocrine and behavioral responses to exposure to
an infant in male prairie voles. J. Neuroendocrinol. 24, 874–886. doi: 10.1111/j.
1365-2826.2012.02301.x
Kéri, S., and Kiss, I. (2011). Oxytocin response in a trust game and habituation of
arousal. Physiol. Behav. 102, 221–224. doi: 10.1016/j.physbeh.2010.11.011
Kon, I. S., and Losenkov, V. A. (1978). Friendship in adolescence: values and
behavior. J. Marriage Fam. 40, 143–155. doi: 10.2307/350615
Kramer, K. M., Cushing, B. S., Carter, C. S., Wu, J., and Ottinger, M. A. (2002).
Chemical and biological validation of an enzyme immunoassay for plasma
oxytocin. Horm. Behav. 41, 476–476.
Ladd, G. W. (1990). Having friends, keeping friends, making friends and
being liked by peers in the classroom: predictors of children’s early school
adjustment. Child Dev. 61, 1081–1100. doi: 10.1111/j.1467-8624.1990.tb0
2843.x
Landgraf, R., and Neumann, I. D. (2004). Vasopressin and oxytocin release within
the brain: a dynamic concept of multiple and variable modes of neuropeptide
communication. Front. Neuroendocrinol. 25, 150–176. doi: 10.1016/j.yfrne.2004.
05.001
Lim, M. M., and Young, L. J. (2004). Vasopressin-dependent neural circuits under-
lying pair bond formation in the monogamous prairie vole. Neuroscience 125,
35–45. doi: 10.1016/j.neuroscience.2003.12.008
Lindburg, D. G. (1971). “The rhesus monkey in north India: an ecological and
behavioral study,” in Primate Behavior: Developments in Field and Laboratory
Research, ed L. A. Rosenblum (New York: Academic Press), 1–106.
Mason, W. A., and Mendoza, S. P. (1998). Generic aspects of primate attachments:
parents, offspring and mates. Psychoneuroendocrinology 23, 765–778. doi: 10.
1016/s0306-4530(98)00054-7
Mazurek, M. O., and Kanne, S. M. (2010). Friendship and internalizing symptoms
among children and adolescents with ASD. J. Autism Dev. Disord. 40, 1512–
1520. doi: 10.1007/s10803-010-1014-y
Miller, M., Bales, K. L., Taylor, S. L., Yoon, J., Hostetler, C. M., Carter, C. S.,
et al. (2013). Oxytocin and vasopressin in children and adolescents with autism
spectrum disorders: sex differences and associations with symptoms. Autism.
Res. 6, 91–102. doi: 10.1002/aur.1270
Modahl, C., Green, L. A., Fein, D., Morris, M., Waterhouse, L., Feinstein, C., et al.
(1998). Plasma oxytocin levels in autistic children. Biol. Psychiatry 43, 270–277.
doi: 10.1016/s0006-3223(97)00439-3
Nangle, D. W., Erdley, C. A., Newman, J. E., Mason, C. A., and Carpenter,
E. M. (2003). Popularity, friendship quantity and friendship quality: interactive
influences on children’s loneliness and depression. J. Clin. Child Adolesc. Psychol.
32, 546–555. doi: 10.1207/s15374424jccp3204_7
Nelson, E. E., and Winslow, J. T. (2009). Non-human primates: model animals for
developmental psychopathology. Neuropsychopharmacology 34, 90–105. doi: 10.
1038/npp.2008.150
Norman, G. J., Cacioppo, J. T., Morris, J. S., Malarkey, W. B., Berntson, G. G.,
and Devries, A. C. (2011). Oxytocin increases autonomic cardiac control:
moderation by loneliness. Biol. Psychol. 86, 174–180. doi: 10.1016/j.biopsycho.
2010.11.006
Olff, M., Frijling, J. L., Kubzansky, L. D., Bradley, B., Ellenbogen, M. A., Cardoso, C.,
et al. (2013). The role of oxytocin in social bonding, stress regulation and mental
health: an update on the moderating effects of context and interindividual
differences. Psychoneuroendocrinology 38, 1883–1894. doi: 10.1016/j.psyneuen.
2013.06.019
Pedersen, C. A., and Prange, A. J. Jr. (1979). Induction of maternal behavior in
virgin rats after intracerebroventricular administration of oxytocin. Proc. Natl.
Acad. Sci. U S A 76, 6661–6665. doi: 10.1073/pnas.76.12.6661
Poirier, F. E., and Smith, E. O. (1974). Socializing functions of primate play. Integr.
Comp. Biol. 14, 275–287. doi: 10.1093/icb/14.1.275
Reza, A. M., Naser, A., and Saeed, K. (2011). Transient post-exercise hyper-
perspiration of forehead area. Afr. J. Biotechnol. 10, 12984–12990. doi: 10.5897/
AJB10.1803
Rilling, J. K., Demarco, A. C., Hackett, P. D., Thompson, R., Ditzen, B., Patel,
R., et al. (2012). Effects of intranasal oxytocin and vasopressin on cooperative
behavior and associated brain activity in men. Psychoneuroendocrinology 37,
447–461. doi: 10.1016/j.psyneuen.2011.07.013
Rowley, E., Chandler, S., Baird, G., Simonoff, E., Pickles, A., Loucas, T., et al. (2012).
The experience of friendship, victimization and bullying in children with an
autism spectrum disorder: associations with child characteristics and school
placement. Res. Autism Spectr. Disord. 6, 1126–1134. doi: 10.1016/j.rasd.2012.
03.004
Rubin, K. H., Dwyer, K. M., Booth-Laforce, C., Kim, A. H., Burgess, K. B., and
Rose-Krasnor, L. (2004). Attachment, friendship and psychosocial functioning
in early adolescence. J. Early Adolesc. 24, 326–356. doi: 10.1177/02724316042
68530
Scheele, D., Striepens, N., Gunturkun, O., Deutschlander, S., Maier, W., Kendrick,
K. M., et al. (2012). Oxytocin modulates social distance between males and
females. J. Neurosci. 32, 16074–16079. doi: 10.1523/JNEUROSCI.2755-12.2012
Schneiderman, I., Zagoory-Sharon, O., Leckman, J. F., and Feldman, R. (2012).
Oxytocin during the initial stages of romantic attachment: relations to couples’
interactive reciprocity. Psychoneuroendocrinology 37, 1277–1285. doi: 10.1016/j.
psyneuen.2011.12.021
Silk, J. B. (2002). Using the ‘F’-word in primatology. Behaviour 139, 421–446.
doi: 10.1163/156853902760102735
Silk, J. B., Alberts, S. C., and Altmann, J. (2003). Social bonds of female baboons
enhance infant survival. Science 302, 1231–1234. doi: 10.1126/science.1088580
Silk, J. B., Beehner, J. C., Bergman, T. J., Crockford, C., Engh, A. L., Moscovice, L. R.,
et al. (2009). The benefits of social capital: close social bonds among female
baboons enhance offspring survival. Proc. Biol. Sci. 276, 3099–3104. doi: 10.
1098/rspb.2009.0681
Silk, J. B., Beehner, J. C., Bergman, T. J., Crockford, C., Engh, A. L., Moscovice,
L. R., et al. (2010). Strong and consistent social bonds enhance the longevity of
female baboons. Curr. Biol. 20, 1359–1361. doi: 10.1016/j.cub.2010.05.067
Smuts, B. B. (1985). Sex and Friendship in Baboons. New York: Aldine.
Sofroniew, M. V. (1985). “Vasopressin, oxytocin and their related neurophysins,”
in Handbook of Chemical Neuroanatomy, eds A. Bjorklund and T. Hokfelt
(Amsterdam: Elsevier), 93–165.
Spinka, M., Newberry, R. C., and Bekoff, M. (2001). Mammalian play: training for
the unexpected. Q. Rev. Biol. 76, 141–168. doi: 10.1086/393866
Strathearn, L., Iyengar, U., Fonagy, P., and Kim, S. (2012). Maternal oxytocin
response during mother-infant interaction: associations with adult tempera-
ment. Horm. Behav. 61, 429–435. doi: 10.1016/j.yhbeh.2012.01.014
Stribley, J. M., and Carter, C. S. (1999). Developmental exposure to vasopressin
increases aggression in adult prairie voles. Proc. Natl. Acad. Sci. U S A 96, 12601–
12604. doi: 10.1073/pnas.96.22.12601
Suomi, S. J. (2005). Mother-infant attachment, peer relationships and the devel-
opment of social networks in rhesus monkeys. Hum. Dev. 48, 67–79. doi: 10.
1159/000083216
Tachibana, M., Kagitani-Shimono, K., Mohri, I., Yamamoto, T., Sanefuji, W.,
Nakamura, A., et al. (2013). Long-term administration of intranasal oxytocin
is a safe and promising therapy for early adolescent boys with autism spectrum
disorders. J. Child Adolesc. Psychopharmacol. 23, 123–127. doi: 10.1089/cap.
2012.0048
Taylor, S. E., Gonzaga, G. C., Klein, L. C., Hu, P., Greendale, G. A., and
Seeman, T. E. (2006). Relation of oxytocin to psychological stress responses and
hypothalamic-pituitary-adrenal axis activity in older women. Psychosom. Med.
68, 238–245. doi: 10.1097/01.psy.0000203242.95990.74
Taylor, S. E., Saphire-Bernstein, S., and Seeman, T. E. (2010). Are plasma oxytocin
in women and plasma vasopressin in men biomarkers of distressed pair-bond
relationships? Psychol. Sci. 21, 3–7. doi: 10.1177/0956797609356507
Thompson, R. R., George, K., Walton, J. C., Orr, S. P., and Benson, J. (2006). Sex-
specific influences of vasopressin on human social communication. Proc. Natl.
Acad. Sci. U S A 103, 7889–7994. doi: 10.1073/pnas.0600406103
Thompson, R., Gupta, S., Miller, K., Mills, S., and Orr, S. (2004). The effects
of vasopressin on human facial responses related to social communication.
Psychoneuroendocrinology 29, 35–48. doi: 10.1016/s0306-4530(02)00133-6
Thorsteinsson, E. B., and James, J. E. (1999). A meta-analysis of the effects of
experimental manipulations of social support during laboratory stress. Psychol.
Health 14, 869–886. doi: 10.1080/08870449908407353
Uchino, B. N., Cacioppo, J. T., and Kiecolt-Glaser, J. K. (1996). The relationship
between social support and physiological processes: a review with emphasis on
Frontiers in Behavioral Neuroscience www.frontiersin.org August 2014 | Volume 8 | Article 295 | 12