This study examined the impact of short-wavelength (blue) light exposure on the cortisol awakening response (CAR) in sleep-restricted adolescents. Eighteen adolescents aged 12-17 participated in three overnight sessions at least one week apart with different light exposure scenarios in the evening and morning. Exposure to 40 lux of 470nm blue light for 80 minutes after waking significantly enhanced the CAR compared to exposure to dim light, as measured by cortisol levels in saliva samples collected every 20 minutes. The findings suggest that morning exposure to short-wavelength blue light may help prepare sleep-restricted adolescents for the day by enhancing their CAR and ability to deal with stressors.
Endocytosis and Endosome Trafficking: Roles in Coronavirus Uptake and Cell Si...InsideScientific
To learn more and watch the webinar, visit:
https://insidescientific.com/webinar/endocytosis-endosome-trafficking-coronavirus-uptake-cell-signaling-aps
Endocytosis and Endosome Trafficking: Roles in Coronavirus Uptake and Cell Signaling
Click to share on Twitter (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on Email (Opens in new window)
ON DEMAND
Ole Petersen, Roop Mallik and Erwin Neher share late-breaking research looking at endocytosis and calcium signaling in the context of SARS-CoV-2, organelle transport and calcium imaging. This webinar is brought to you by APS’ new journal, Function, and part of their Physiology in Focus learning series.
REGISTER
During this exclusive live webinar, Ole Petersen, Roop Mallik and Erwin Neher discuss how the COVID-19 virus uses receptor-mediated endocytosis to gain entry into host cells, how motor proteins guide endosomes and phagosomes from the cell surface to lysosomes, and how intracellular calcium buffering can be used to modulate cell signaling and calcium imaging.
Endocytic Uptake of SARS-CoV-2: The Critical Roles of pH, Ca2+ and NAADP
Ole Petersen, CBE, FRS
Very recent work shows that SARS-CoV-2 enters our cells through receptor-mediated endocytosis, dependent on an endosomal bafilomycin-sensitive proton pump as well as two-pore channels (TPCs). Physiological intracellular Ca2+ signals, mediated by the messenger nicotinic acid adenine dinucleotide phosphate (NAADP), depend on the very same proton pump and TPCs. Two hitherto completely separate research fields, namely molecular virology and cellular Ca2+ signaling physiology are now coming together, creating exciting new research opportunities.
Trafficking of Endosomes and Phagosomes: Geometry, Force and Cholesterol
Roop Mallik, PhD
Uptake of material from the external world by endocytosis/phagocytosis supplies nutrients to cells, and is also critical for cell signaling. The journey of endosomes/phagosomes begins at the cell periphery and ends at lysosomes near the cell center. I will discuss how the balance of forces generated by antagonistic motor proteins guides this journey, and how lipids are emerging as a master-controller of this balance.
Calcium Buffering in Endo- and Exocytosis Studies
Erwin Neher, FRS
Researchers use calcium-chelators (buffers) to manipulate levels of free intracellular calcium concentration ([Ca2+]i) and to shape Calcium signals. Unlike pH buffers, which are used to strictly control pH levels, calcium buffers inside a living cell may not influence the steady-state level of [Ca2+]i at all, but rather slow-down [Ca2+]i-changes induced either endogenously or by the experimenter. Such properties and their consequences on Ca2+-imaging will be discussed.
Prophylaxis,Treatment of Acute Toxic Radiation Cerebrovascular Syndrome Asso...Dmitri Popov
This document discusses acute cerebrovascular radiation syndrome associated with long-term space flight to Mars. It describes the potential risks of radiation exposure during space travel, including the development of radiation neurotoxins that can disrupt the blood-brain barrier and blood flow. It then presents a grading system for acute cerebrovascular radiation syndrome based on neurological symptoms. Finally, it discusses the roles of cannabinoids and their receptors in potentially helping to prevent or treat the biological effects of radiation exposure.
Protection of humans during long space flight. using cannabis to reduce biol...Dmitri Popov
Protection of humans during long space flight. using cannabis to reduce biological consequences of high doses of radiation, treat stress, anxiety, and depression Associated with Long-term Space Flight to Mars.
The Brain as a Whole: Executive Neurons and Sustaining Homeostatic GliaInsideScientific
Carl Petersen and Alexei Verkhratsky share their research on homeostatic neuroglia and imaging of neuronal network function. This webinar is brought to you by APS’ new journal, Function, and part of their Physiology in Focus learning series.
During this exclusive live webinar, Carl Petersen and Alexei Verkhratsky discuss astrocyte-mediated homeostatic control of the central nervous system, and how optical and 2-photon microscopy can be used for functional neuroimaging.
Imaging Neuronal Function
Carl Petersen, PhD
Highly dynamic and spatially distributed neuronal circuits in the brain control mammalian behavior. Through technological advances, optical measurements of neuronal function can now be carried out in behaving mice at multiple scales. Wide-field imaging allows the dynamic interactions between different brain areas to be studied as sensory information is processed and transformed into behavioral output. Within a brain region, two-photon microscopy can be used to image the neuronal network activity with cellular resolution allowing different types of projection neurons to be distinguished. Together optical methods provide versatile tools for causal mechanistic understanding of neuronal network function in mice.
Astrocytes: indispensable neuronal supporters in sickness and in health
Alexei Verkhratsky, MD, PhD, DSc
The nervous system is composed of two arms: the executive neurons and the homeostatic neuroglia. The neurons require energy, support, and protection, all of which is provided by the neuroglia. Astrocytes, the principal homeostatic cells of the brain and spinal cord, are tightly integrated into the neural networks and act within the context of the neural tissue. As astrocytes control the homeostasis of the central nervous system at all levels of organization, from the molecular to the whole organ level, we can begin to define and understand brain vulnerabilities to aging and diseases.
Single-Cell Electrophysiology and 2-Photon Imaging in Awake Mice with 2D-Loco...InsideScientific
In this webinar sponsored by Neurotar, experts present their research utilizing the Mobile HomeCage®, an experimental tool which ensures the stability required for high-precision neurophysiological techniques while allowing mice to navigate and explore their environment.
Case Study #1:
Dr. Sarah Stuart and Dr. Jon Palacios-Filardo of the University of Bristol present their studies combining analysis of goal-directed behavior with whole-cell recordings from the hippocampus of awake mice. The researchers share useful tips for the surgery protocol and for adjusting the head fixation angle in order to facilitate mouse motility and exploratory behavior.
Case Study #2:
Dr. Alexander Dityatev and Weilun Sun from the German Center for Neurodegenerative Diseases (DZNE) discuss 2-photon imaging of fluorescently labeled microglia in vivo in the context of neurodegenerative disease. They also present their recent data on the effects of different anesthetics on the microglial response to localized laser injury.
Case Study #3:
Dr. Norbert Hájos from the Hungarian Academy of Sciences presents his lab’s research into the amygdala’s role in reward-driven behavior. He shares the challenges of making single-unit recordings using silicon probes during mouse locomotion and subsequent morphological identification of active neurons in the amygdala.
Key topics covered during this webinar include:
- Requirements for stable single-cell recordings and 2-photon imaging in behaving mice
- Challenges of combining high-precision techniques with behavioral research
- Methodological considerations for improving exploratory behavior in head-fixed mice
- Quantitative analysis of microglial function using 2-photon microscopy in awake mice
- Recording neuronal activity in the amygdala of awake mice followed by morphological identification of recorded neurons
The impact of a week of simulated night work on sleep, circadian phase, and p...2011Whiteout2011
This document summarizes a study that examined the impact of one week of simulated night work on sleep, circadian rhythms, and performance in 15 healthy subjects. The key findings were:
1) Nighttime performance on a vigilance task significantly improved across the week, suggesting adaptation occurred.
2) Daytime sleep quality and quantity were not negatively affected, though total sleep time was slightly reduced each day.
3) A small cumulative sleep debt of 3.53 hours built up by the end of the week, but this did not further impact nighttime performance.
4) Circadian rhythms, as measured by melatonin levels, significantly shifted across the week to better align with the simulated night work schedule
Objective and Study Design: This was a cross-sectional study purposed to observe the effects of led bulbs and artificial lights on human health and its physiological considerations on sleep.
Our study addressed two goals. Our first goal was to determine the extent to which light pollution was perceived as a problem by the people. Our second goal was to recommend
applicable lighting ordinances for reducing light pollution. Material and Methods: This study was conducted at All India Institute of Medical Sciences hospital, Bhopal and Narayana medical college, Nellore during the period between May 2014 and August 2015. Three hundred human volunteers, 123 female and 177 male, ages of 18 and 55 were studied in a two-part experiment, which included one Sleep questionnaire regarding light pollution to study each individual's
normal body conditions, and an Assay of melatonin in saliva. Results: The results showed that many participants have a long history of sleeping problems. They usually take at least an hour to fall asleep and tend to wake up frequently throughout the night and feel poorly rested in the morning. The salivary melatonin levels also declined at night due to progressive exposure to artificial light. Conclusion: Through our research, we have obtained data that strongly suggest that light pollution is adversely affecting public health, causing them to experience sleep loss, visual fatigue, weariness, anxiety, and depression.
Part 2 of 2 of lecture series introducing undergraduate neuroscience students to the core electrophysiological and imaging techniques used to study neuronal activity.
Endocytosis and Endosome Trafficking: Roles in Coronavirus Uptake and Cell Si...InsideScientific
To learn more and watch the webinar, visit:
https://insidescientific.com/webinar/endocytosis-endosome-trafficking-coronavirus-uptake-cell-signaling-aps
Endocytosis and Endosome Trafficking: Roles in Coronavirus Uptake and Cell Signaling
Click to share on Twitter (Opens in new window)Click to share on LinkedIn (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on Email (Opens in new window)
ON DEMAND
Ole Petersen, Roop Mallik and Erwin Neher share late-breaking research looking at endocytosis and calcium signaling in the context of SARS-CoV-2, organelle transport and calcium imaging. This webinar is brought to you by APS’ new journal, Function, and part of their Physiology in Focus learning series.
REGISTER
During this exclusive live webinar, Ole Petersen, Roop Mallik and Erwin Neher discuss how the COVID-19 virus uses receptor-mediated endocytosis to gain entry into host cells, how motor proteins guide endosomes and phagosomes from the cell surface to lysosomes, and how intracellular calcium buffering can be used to modulate cell signaling and calcium imaging.
Endocytic Uptake of SARS-CoV-2: The Critical Roles of pH, Ca2+ and NAADP
Ole Petersen, CBE, FRS
Very recent work shows that SARS-CoV-2 enters our cells through receptor-mediated endocytosis, dependent on an endosomal bafilomycin-sensitive proton pump as well as two-pore channels (TPCs). Physiological intracellular Ca2+ signals, mediated by the messenger nicotinic acid adenine dinucleotide phosphate (NAADP), depend on the very same proton pump and TPCs. Two hitherto completely separate research fields, namely molecular virology and cellular Ca2+ signaling physiology are now coming together, creating exciting new research opportunities.
Trafficking of Endosomes and Phagosomes: Geometry, Force and Cholesterol
Roop Mallik, PhD
Uptake of material from the external world by endocytosis/phagocytosis supplies nutrients to cells, and is also critical for cell signaling. The journey of endosomes/phagosomes begins at the cell periphery and ends at lysosomes near the cell center. I will discuss how the balance of forces generated by antagonistic motor proteins guides this journey, and how lipids are emerging as a master-controller of this balance.
Calcium Buffering in Endo- and Exocytosis Studies
Erwin Neher, FRS
Researchers use calcium-chelators (buffers) to manipulate levels of free intracellular calcium concentration ([Ca2+]i) and to shape Calcium signals. Unlike pH buffers, which are used to strictly control pH levels, calcium buffers inside a living cell may not influence the steady-state level of [Ca2+]i at all, but rather slow-down [Ca2+]i-changes induced either endogenously or by the experimenter. Such properties and their consequences on Ca2+-imaging will be discussed.
Prophylaxis,Treatment of Acute Toxic Radiation Cerebrovascular Syndrome Asso...Dmitri Popov
This document discusses acute cerebrovascular radiation syndrome associated with long-term space flight to Mars. It describes the potential risks of radiation exposure during space travel, including the development of radiation neurotoxins that can disrupt the blood-brain barrier and blood flow. It then presents a grading system for acute cerebrovascular radiation syndrome based on neurological symptoms. Finally, it discusses the roles of cannabinoids and their receptors in potentially helping to prevent or treat the biological effects of radiation exposure.
Protection of humans during long space flight. using cannabis to reduce biol...Dmitri Popov
Protection of humans during long space flight. using cannabis to reduce biological consequences of high doses of radiation, treat stress, anxiety, and depression Associated with Long-term Space Flight to Mars.
The Brain as a Whole: Executive Neurons and Sustaining Homeostatic GliaInsideScientific
Carl Petersen and Alexei Verkhratsky share their research on homeostatic neuroglia and imaging of neuronal network function. This webinar is brought to you by APS’ new journal, Function, and part of their Physiology in Focus learning series.
During this exclusive live webinar, Carl Petersen and Alexei Verkhratsky discuss astrocyte-mediated homeostatic control of the central nervous system, and how optical and 2-photon microscopy can be used for functional neuroimaging.
Imaging Neuronal Function
Carl Petersen, PhD
Highly dynamic and spatially distributed neuronal circuits in the brain control mammalian behavior. Through technological advances, optical measurements of neuronal function can now be carried out in behaving mice at multiple scales. Wide-field imaging allows the dynamic interactions between different brain areas to be studied as sensory information is processed and transformed into behavioral output. Within a brain region, two-photon microscopy can be used to image the neuronal network activity with cellular resolution allowing different types of projection neurons to be distinguished. Together optical methods provide versatile tools for causal mechanistic understanding of neuronal network function in mice.
Astrocytes: indispensable neuronal supporters in sickness and in health
Alexei Verkhratsky, MD, PhD, DSc
The nervous system is composed of two arms: the executive neurons and the homeostatic neuroglia. The neurons require energy, support, and protection, all of which is provided by the neuroglia. Astrocytes, the principal homeostatic cells of the brain and spinal cord, are tightly integrated into the neural networks and act within the context of the neural tissue. As astrocytes control the homeostasis of the central nervous system at all levels of organization, from the molecular to the whole organ level, we can begin to define and understand brain vulnerabilities to aging and diseases.
Single-Cell Electrophysiology and 2-Photon Imaging in Awake Mice with 2D-Loco...InsideScientific
In this webinar sponsored by Neurotar, experts present their research utilizing the Mobile HomeCage®, an experimental tool which ensures the stability required for high-precision neurophysiological techniques while allowing mice to navigate and explore their environment.
Case Study #1:
Dr. Sarah Stuart and Dr. Jon Palacios-Filardo of the University of Bristol present their studies combining analysis of goal-directed behavior with whole-cell recordings from the hippocampus of awake mice. The researchers share useful tips for the surgery protocol and for adjusting the head fixation angle in order to facilitate mouse motility and exploratory behavior.
Case Study #2:
Dr. Alexander Dityatev and Weilun Sun from the German Center for Neurodegenerative Diseases (DZNE) discuss 2-photon imaging of fluorescently labeled microglia in vivo in the context of neurodegenerative disease. They also present their recent data on the effects of different anesthetics on the microglial response to localized laser injury.
Case Study #3:
Dr. Norbert Hájos from the Hungarian Academy of Sciences presents his lab’s research into the amygdala’s role in reward-driven behavior. He shares the challenges of making single-unit recordings using silicon probes during mouse locomotion and subsequent morphological identification of active neurons in the amygdala.
Key topics covered during this webinar include:
- Requirements for stable single-cell recordings and 2-photon imaging in behaving mice
- Challenges of combining high-precision techniques with behavioral research
- Methodological considerations for improving exploratory behavior in head-fixed mice
- Quantitative analysis of microglial function using 2-photon microscopy in awake mice
- Recording neuronal activity in the amygdala of awake mice followed by morphological identification of recorded neurons
The impact of a week of simulated night work on sleep, circadian phase, and p...2011Whiteout2011
This document summarizes a study that examined the impact of one week of simulated night work on sleep, circadian rhythms, and performance in 15 healthy subjects. The key findings were:
1) Nighttime performance on a vigilance task significantly improved across the week, suggesting adaptation occurred.
2) Daytime sleep quality and quantity were not negatively affected, though total sleep time was slightly reduced each day.
3) A small cumulative sleep debt of 3.53 hours built up by the end of the week, but this did not further impact nighttime performance.
4) Circadian rhythms, as measured by melatonin levels, significantly shifted across the week to better align with the simulated night work schedule
Objective and Study Design: This was a cross-sectional study purposed to observe the effects of led bulbs and artificial lights on human health and its physiological considerations on sleep.
Our study addressed two goals. Our first goal was to determine the extent to which light pollution was perceived as a problem by the people. Our second goal was to recommend
applicable lighting ordinances for reducing light pollution. Material and Methods: This study was conducted at All India Institute of Medical Sciences hospital, Bhopal and Narayana medical college, Nellore during the period between May 2014 and August 2015. Three hundred human volunteers, 123 female and 177 male, ages of 18 and 55 were studied in a two-part experiment, which included one Sleep questionnaire regarding light pollution to study each individual's
normal body conditions, and an Assay of melatonin in saliva. Results: The results showed that many participants have a long history of sleeping problems. They usually take at least an hour to fall asleep and tend to wake up frequently throughout the night and feel poorly rested in the morning. The salivary melatonin levels also declined at night due to progressive exposure to artificial light. Conclusion: Through our research, we have obtained data that strongly suggest that light pollution is adversely affecting public health, causing them to experience sleep loss, visual fatigue, weariness, anxiety, and depression.
Part 2 of 2 of lecture series introducing undergraduate neuroscience students to the core electrophysiological and imaging techniques used to study neuronal activity.
Brief description of various neuroimaging modalities used in psychiatry which help in early detection, diagnosis and treatment of various neuropsychiatric disorders.
Ultrasound Stimulation for Peripheral Nerve Repair v7Emily Ashbolt
Ultrasound stimulation increases neurite branching and outgrowth in peripheral neurons. Higher intensity ultrasound led to greater neurite branching and total outgrowth compared to lower intensities and untreated controls. Ultrasound also increased the metabolic activity of Schwann cells, peripheral glial cells that enhance neurite outgrowth. These findings suggest ultrasound may promote peripheral nerve regeneration by stimulating neuronal and glial responses. Further study is needed to understand the cellular mechanisms and potential for ultrasound as a non-invasive therapy for peripheral nerve injuries.
scanner acoustic noise on intrinsic brain activity during auditory stimulatio...Ji-Hoon Min
This document summarizes a study that investigated the effects of scanner background noise (SBN) on intrinsic connectivity networks (ICNs) during auditory stimulation. Independent component analysis identified 19 ICNs from fMRI data collected using sparse temporal acquisition (STA) and continuous acquisition (CA). Several networks, including the auditory, default mode, salience, and frontoparietal networks, showed greater activity in the STA which has reduced SBN compared to CA. Most network time courses correlated with the stimulus cycles in STA but fewer did in CA. The dorsal default mode and salience networks also showed stronger correlations between their time courses and the stimulus waveform in STA versus CA. The results suggest that SBN influences
Light, health and well being v jens christoffersen 230909Dania Abdel-aziz
This document discusses the visual and non-visual effects of light on health and well-being. It describes how light impacts visual performance and mood, is important for maintaining circadian rhythms and melatonin levels, and how modern lifestyles with less natural light exposure may disrupt biological functions. Specifically, it notes that daylight provides the right intensity and spectrum of light to support visual tasks and regulate circadian rhythms, while artificial light alone often lacks the qualities needed to fully stimulate both systems.
This study implemented a quiet time protocol in a neuro-ICU to reduce noise and light levels twice daily to allow patients to sleep. Noise and light levels were measured before, during, and after quiet time and patients' sleep behaviors were observed. The results showed that noise and light levels were significantly lower during quiet time. Patients were also significantly more likely to be observed sleeping during quiet time periods compared to before and after. The goal of allowing patients rest and sleep during quiet time periods was achieved through reducing environmental stimuli in the ICU.
Fast Functional Magnetic Resonance Imaging (fast fMRI): uses MRI to measure nerve or brain activity directly
Uses MRI to detect the electromagnetic field that is generated by ionic currents (action potential)
Significance of Brain imaging in Psychiatry. Most of the major Psychiatric disorders are associated with statistically significant differences on various Neuroimaging measures, when comparing groups of patients and controls.
Electrophysiology of Human Native Receptors in Neurological and Mental DisordersInsideScientific
Dr. Agenor Limon presents research integrating functional metrics with large anatomical, transcriptomic, and proteomic datasets to evaluate the relationship between synaptic E/I ratio and behavioral abnormalities across postmortem intervals and brain banks.
Alterations in synaptic function have been found in transcriptomic, genetic, and proteomic studies of neurological and mental disorders. Clinical and preclinical studies suggest that synaptic dysfunction and behavioral abnormalities in disorders like Alzheimer’s disease and schizophrenia may be mechanistically linked to the emergence of imbalances between excitatory (E) and inhibitory (I) receptors. However, until recently, the electrophysiological E/I synaptic ratio had only been measured in animal models.
Using pioneering methods developed in the lab including reactivation and microtransplantation of synaptic receptors from frozen human brains, Dr. Agenor Limon’s research team has obtained electrophysiological metrics of global synaptic E/I ratios in cortical brain regions of subjects that were affected by Alzheimer’s Disease and synaptic measurements in schizophrenia.
In this webinar, Dr. Agenor Limon will present recent research integrating functional metrics with large anatomical, transcriptomic, and proteomic datasets to evaluate the relationship between synaptic E/I ratio and behavioral abnormalities across postmortem intervals and brain banks.
Key Topics Include:
- Understand the global synaptic excitation to inhibition ratio between excitatory and inhibitory synaptic receptors determined from reactivated frozen human brain tissue
- Understand the relationship between electrophysiological metrics of receptor function and multi-omic data in neurodegenerative disorders
- Understand the role of deviations of the excitation to inhibition ratio with clinical presentation in Alzheimer’s disease
Functional magnetic resonance imaging (fMRI) indirectly measures brain activity by detecting changes in blood flow and oxygenation. It uses the difference in magnetic properties between oxygenated and deoxygenated hemoglobin, known as the blood oxygen level dependent (BOLD) signal. The BOLD signal is slow and noisy, peaks around 6 seconds after stimulation, and involves subtracting conditions to identify statistically significant activity changes. fMRI data is overlaid on high-resolution structural scans and analyzed using specialized maps of visual and other functional areas.
Predicting Subjective Sleep Quality Using Objective Measurements in Older AdultsReza Sadeghi
This document summarizes Reza Sadeghi's dissertation defense on predicting subjective sleep quality using objective measurements in older adults. The document outlines the importance of sleep quality prediction, a brief review of sleep physiology including sleep stages, existing challenges in sleep assessment, and the proposed methods. The proposed methods involve using machine learning techniques and extracting features from physiological signals collected by wearable sensors to predict sleep quality, with a focus on predicting sleep quality in caregivers of people with dementia and enhancing prediction models using electronic health records and heart rate variability data.
Optogenetics is a technique that uses light to control neurons that have been genetically modified to express light-sensitive ion channels. It allows scientists to precisely stimulate or silence neural activity by exposing specific neurons to light. The first demonstration of optogenetics in mammalian neurons used channelrhodopsin, a light-activated ion channel from algae, to activate neurons with light. Optogenetics holds promise for advancing understanding of brain function and developing new treatments for neurological disorders like Parkinson's disease, epilepsy, and blindness through targeted neuromodulation with light. Challenges include improving light-sensitive tools and light sources to target deeper brain regions.
Sensorimotor Network Development During Early Postnatal Life in the Awake and...InsideScientific
In the last decades, electrophysiological and imaging-based approaches provided significant new insights into the mechanisms of neuronal development. Nevertheless, many important questions remain unanswered. How does the fine control of a motor output develop? How does sensorimotor integration in the early and subsequent phases of brain development shape behavior? How does sensorimotor development evolve in awake and sleeping states? What role do myoclonic twitches play in this process?
Answering these questions requires performing high-precision tests in the brain of non-anesthetized animals across sleep and wake during the early stages of their postnatal development. Such tests require head-fixation apparatus suitable for neonatal and juvenile rodents. The Mobile HomeCage combines a stable head-fixation with an air-lifted cage that closely resembles laboratory rodents’ natural habitat – an optimal platform for studying early postnatal brain development.
In this webinar, Dr. Cavaccini (Prof. Karayannis’s lab at the Brain Research Institute, University of Zurich) and Dr. Dooley (Prof. Blumberg’s lab at the University of Iowa), share their insights into the development of rodent sensorimotor neuronal circuits during early postnatal life. They elucidate the cortical and subcortical mechanisms involved in the development of sensorimotor circuitry during wakefulness (in a mouse model) and REM sleep (in a rat model).
Key Takeaways
Dr. Anna Cavaccini:
- Anatomical and functional changes occur at the striatal level before and after the onset of different sensory modalities
- Locomotor activity changes throughout early development, and it correlates with striatal function
- Sensory information coming from whiskers affects locomotion and striatal function before and after the onset of different sensory modalities
Dr. James Dooley:
- Myoclonic twitches in REM sleep continue to trigger cortical and thalamic activity beyond the early postnatal period
- Twitch-related thalamic activity is spatiotemporally refined by the third postnatal week
- Motor thalamus activity reflects an internal model of movement produced by twitches and is dependent on the cerebellar output
Neuroimaging and its implications in psychiatryRupinder Oberoi
This document discusses various neuroimaging techniques used to study the structure and function of the living human brain, including their applications and limitations. It describes computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), functional MRI (fMRI), and single photon emission computed tomography (SPECT). CT and MRI are used to examine brain structure, while fMRI, MRS and SPECT provide insights into brain function by detecting changes in blood flow, metabolism or radiotracer distribution associated with neuronal activity. These techniques have advanced understanding of neurological and psychiatric disorders but each has specific strengths and weaknesses for clinical or research applications.
fMRI technology uses the nuclear magnetic resonance (NMR) phenomenon to form images of neural activity in the brain. It relies on the different magnetic properties of oxygenated and deoxygenated hemoglobin. When neurons are active in a region of the brain, blood flow to that region increases, altering the ratio of oxygenated to deoxygenated hemoglobin and causing a change in the MRI signal. Spatial encoding techniques allow fMRI to locate these signal changes within the brain and form a 3D image showing patterns of neural activity.
EEG and Telemetry: Best Practices for Managing Large Data Sets to Investigate...InsideScientific
In this webinar sponsored by Data Sciences International, Dr. Marcio Furtado presents his research highlighting the importance of anomalous EEG detection to study experimental epilepsy and assess the efficacy of potential anticonvulsants and neuroprotectants. He also discusses why continuous EEG monitoring at a high sampling rate is critical to properly detect seizures and how to effectively deal with large telemetry data sets.
Watch this webinar to learn:
- Why neural hyper-synchronization (seizure activity) can result in permanent brain damage
- Tips for organizing, standardizing, and batch processing large data sets
- What features can be extracted from large EEG data sets
- Why inadequate sampling rates can lead to signal aliasing and how to avoid it
- How telemetry can be used to continuously monitor EEG and assess seizure activity in animal models of epilepsy
Sleep quality prediction in caregivers using physiological signalsReza Sadeghi
The presentation slides of the following paper:
R. Sadeghi, T. Banerjee, J.C. Hughes, L.W. Lawhorne, Sleep quality prediction in caregivers using physiological signals, Computers in Biology and Medicine (2019), doi:https://doi.org/10.1016/j.compbiomed.2019.05.010.
Optogenetics is a technique developed in 2006 that uses light to control neurons by inserting light-sensitive ion channel genes into brain cells. It works by using channelrhodopsin genes to excite neurons or halorhodopsin genes to inhibit neurons when light hits the nerve cell. This allows precise activation or stopping of specific neuron groups with high temporal resolution. Optogenetics offers potential treatment for conditions like anxiety, addiction, chronic pain, and sleep disorders by providing a less invasive way to stimulate or inhibit neurons compared to electrical methods. However, challenges include introducing foreign genes into the brain and technical issues like fiber optics posing infection risks or requiring heavy batteries.
This document provides an overview of neuroimaging techniques used in psychiatry. It discusses various structural and functional neuroimaging methods including CT, MRI, fMRI, SPECT, PET, DTI, and MRS. CT and MRI provide structural images while fMRI, SPECT, PET, and MRS assess brain function by measuring activity, blood flow, and metabolite levels. Neuroimaging has improved understanding of psychiatric conditions and informed research on the pathophysiology of disorders.
This document discusses the potential health risks of LED lighting, particularly from exposure to blue light at night. It summarizes research finding links between light at night and increased risks of breast cancer, diabetes, and sleep disorders. Studies suggest that blue light can disrupt circadian rhythms by suppressing melatonin production. While direct health effects of LEDs are unclear, late-evening exposure to light may impact circadian rhythms. Variables like light spectrum, intensity, duration and timing of exposure are important. High color temperature white LEDs contain more short wavelengths of blue light, which can be detrimental to health. Younger and older individuals may be more susceptible to circadian disruption from light at night.
Low Level Laser Therapy and Memory Enhancement: Effect of Different Energy DosesIJERD Editor
Short-term memory is the information we are currently aware of or thinking about. The amount of information that can be stored in short-term memory can vary. An often cited figure is plus or minus seven items, based on the results of a famous experiment on short-term memory. Use of various new techniques to enhance the training module certainly help the learning in college age population, but doesnot provide any solution to the biologically retarding memory due to stress and inflammation of the neurons of the brain. Our research aimed to study the effect different energy doses of Low Level Laser Therapy (LLLT) on memorizing capacity of the young population aged 20years to 30 years. For the purpose two equivalent tests of non-associated meaningful words were used. 106 subjects were divided into in Group A and Group B and each group took the “non-associated memory test” test, followed by Low Level Laser Therapytwice a week for four weeks. At the end of the 30thday an equivalent “non-associated memory test” post test was taken and the data was analyzed. The memory retention score of Group A was increase by 29.7% after 8 applications of LLLT. On the other hand group B showed 2% increase after 8 applications of LLLT. In conclusion low level laser therapy, when used with the correct frequency, powered density and dose can be very effective in increasing the working memory of the test individuals.
Brief description of various neuroimaging modalities used in psychiatry which help in early detection, diagnosis and treatment of various neuropsychiatric disorders.
Ultrasound Stimulation for Peripheral Nerve Repair v7Emily Ashbolt
Ultrasound stimulation increases neurite branching and outgrowth in peripheral neurons. Higher intensity ultrasound led to greater neurite branching and total outgrowth compared to lower intensities and untreated controls. Ultrasound also increased the metabolic activity of Schwann cells, peripheral glial cells that enhance neurite outgrowth. These findings suggest ultrasound may promote peripheral nerve regeneration by stimulating neuronal and glial responses. Further study is needed to understand the cellular mechanisms and potential for ultrasound as a non-invasive therapy for peripheral nerve injuries.
scanner acoustic noise on intrinsic brain activity during auditory stimulatio...Ji-Hoon Min
This document summarizes a study that investigated the effects of scanner background noise (SBN) on intrinsic connectivity networks (ICNs) during auditory stimulation. Independent component analysis identified 19 ICNs from fMRI data collected using sparse temporal acquisition (STA) and continuous acquisition (CA). Several networks, including the auditory, default mode, salience, and frontoparietal networks, showed greater activity in the STA which has reduced SBN compared to CA. Most network time courses correlated with the stimulus cycles in STA but fewer did in CA. The dorsal default mode and salience networks also showed stronger correlations between their time courses and the stimulus waveform in STA versus CA. The results suggest that SBN influences
Light, health and well being v jens christoffersen 230909Dania Abdel-aziz
This document discusses the visual and non-visual effects of light on health and well-being. It describes how light impacts visual performance and mood, is important for maintaining circadian rhythms and melatonin levels, and how modern lifestyles with less natural light exposure may disrupt biological functions. Specifically, it notes that daylight provides the right intensity and spectrum of light to support visual tasks and regulate circadian rhythms, while artificial light alone often lacks the qualities needed to fully stimulate both systems.
This study implemented a quiet time protocol in a neuro-ICU to reduce noise and light levels twice daily to allow patients to sleep. Noise and light levels were measured before, during, and after quiet time and patients' sleep behaviors were observed. The results showed that noise and light levels were significantly lower during quiet time. Patients were also significantly more likely to be observed sleeping during quiet time periods compared to before and after. The goal of allowing patients rest and sleep during quiet time periods was achieved through reducing environmental stimuli in the ICU.
Fast Functional Magnetic Resonance Imaging (fast fMRI): uses MRI to measure nerve or brain activity directly
Uses MRI to detect the electromagnetic field that is generated by ionic currents (action potential)
Significance of Brain imaging in Psychiatry. Most of the major Psychiatric disorders are associated with statistically significant differences on various Neuroimaging measures, when comparing groups of patients and controls.
Electrophysiology of Human Native Receptors in Neurological and Mental DisordersInsideScientific
Dr. Agenor Limon presents research integrating functional metrics with large anatomical, transcriptomic, and proteomic datasets to evaluate the relationship between synaptic E/I ratio and behavioral abnormalities across postmortem intervals and brain banks.
Alterations in synaptic function have been found in transcriptomic, genetic, and proteomic studies of neurological and mental disorders. Clinical and preclinical studies suggest that synaptic dysfunction and behavioral abnormalities in disorders like Alzheimer’s disease and schizophrenia may be mechanistically linked to the emergence of imbalances between excitatory (E) and inhibitory (I) receptors. However, until recently, the electrophysiological E/I synaptic ratio had only been measured in animal models.
Using pioneering methods developed in the lab including reactivation and microtransplantation of synaptic receptors from frozen human brains, Dr. Agenor Limon’s research team has obtained electrophysiological metrics of global synaptic E/I ratios in cortical brain regions of subjects that were affected by Alzheimer’s Disease and synaptic measurements in schizophrenia.
In this webinar, Dr. Agenor Limon will present recent research integrating functional metrics with large anatomical, transcriptomic, and proteomic datasets to evaluate the relationship between synaptic E/I ratio and behavioral abnormalities across postmortem intervals and brain banks.
Key Topics Include:
- Understand the global synaptic excitation to inhibition ratio between excitatory and inhibitory synaptic receptors determined from reactivated frozen human brain tissue
- Understand the relationship between electrophysiological metrics of receptor function and multi-omic data in neurodegenerative disorders
- Understand the role of deviations of the excitation to inhibition ratio with clinical presentation in Alzheimer’s disease
Functional magnetic resonance imaging (fMRI) indirectly measures brain activity by detecting changes in blood flow and oxygenation. It uses the difference in magnetic properties between oxygenated and deoxygenated hemoglobin, known as the blood oxygen level dependent (BOLD) signal. The BOLD signal is slow and noisy, peaks around 6 seconds after stimulation, and involves subtracting conditions to identify statistically significant activity changes. fMRI data is overlaid on high-resolution structural scans and analyzed using specialized maps of visual and other functional areas.
Predicting Subjective Sleep Quality Using Objective Measurements in Older AdultsReza Sadeghi
This document summarizes Reza Sadeghi's dissertation defense on predicting subjective sleep quality using objective measurements in older adults. The document outlines the importance of sleep quality prediction, a brief review of sleep physiology including sleep stages, existing challenges in sleep assessment, and the proposed methods. The proposed methods involve using machine learning techniques and extracting features from physiological signals collected by wearable sensors to predict sleep quality, with a focus on predicting sleep quality in caregivers of people with dementia and enhancing prediction models using electronic health records and heart rate variability data.
Optogenetics is a technique that uses light to control neurons that have been genetically modified to express light-sensitive ion channels. It allows scientists to precisely stimulate or silence neural activity by exposing specific neurons to light. The first demonstration of optogenetics in mammalian neurons used channelrhodopsin, a light-activated ion channel from algae, to activate neurons with light. Optogenetics holds promise for advancing understanding of brain function and developing new treatments for neurological disorders like Parkinson's disease, epilepsy, and blindness through targeted neuromodulation with light. Challenges include improving light-sensitive tools and light sources to target deeper brain regions.
Sensorimotor Network Development During Early Postnatal Life in the Awake and...InsideScientific
In the last decades, electrophysiological and imaging-based approaches provided significant new insights into the mechanisms of neuronal development. Nevertheless, many important questions remain unanswered. How does the fine control of a motor output develop? How does sensorimotor integration in the early and subsequent phases of brain development shape behavior? How does sensorimotor development evolve in awake and sleeping states? What role do myoclonic twitches play in this process?
Answering these questions requires performing high-precision tests in the brain of non-anesthetized animals across sleep and wake during the early stages of their postnatal development. Such tests require head-fixation apparatus suitable for neonatal and juvenile rodents. The Mobile HomeCage combines a stable head-fixation with an air-lifted cage that closely resembles laboratory rodents’ natural habitat – an optimal platform for studying early postnatal brain development.
In this webinar, Dr. Cavaccini (Prof. Karayannis’s lab at the Brain Research Institute, University of Zurich) and Dr. Dooley (Prof. Blumberg’s lab at the University of Iowa), share their insights into the development of rodent sensorimotor neuronal circuits during early postnatal life. They elucidate the cortical and subcortical mechanisms involved in the development of sensorimotor circuitry during wakefulness (in a mouse model) and REM sleep (in a rat model).
Key Takeaways
Dr. Anna Cavaccini:
- Anatomical and functional changes occur at the striatal level before and after the onset of different sensory modalities
- Locomotor activity changes throughout early development, and it correlates with striatal function
- Sensory information coming from whiskers affects locomotion and striatal function before and after the onset of different sensory modalities
Dr. James Dooley:
- Myoclonic twitches in REM sleep continue to trigger cortical and thalamic activity beyond the early postnatal period
- Twitch-related thalamic activity is spatiotemporally refined by the third postnatal week
- Motor thalamus activity reflects an internal model of movement produced by twitches and is dependent on the cerebellar output
Neuroimaging and its implications in psychiatryRupinder Oberoi
This document discusses various neuroimaging techniques used to study the structure and function of the living human brain, including their applications and limitations. It describes computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance spectroscopy (MRS), functional MRI (fMRI), and single photon emission computed tomography (SPECT). CT and MRI are used to examine brain structure, while fMRI, MRS and SPECT provide insights into brain function by detecting changes in blood flow, metabolism or radiotracer distribution associated with neuronal activity. These techniques have advanced understanding of neurological and psychiatric disorders but each has specific strengths and weaknesses for clinical or research applications.
fMRI technology uses the nuclear magnetic resonance (NMR) phenomenon to form images of neural activity in the brain. It relies on the different magnetic properties of oxygenated and deoxygenated hemoglobin. When neurons are active in a region of the brain, blood flow to that region increases, altering the ratio of oxygenated to deoxygenated hemoglobin and causing a change in the MRI signal. Spatial encoding techniques allow fMRI to locate these signal changes within the brain and form a 3D image showing patterns of neural activity.
EEG and Telemetry: Best Practices for Managing Large Data Sets to Investigate...InsideScientific
In this webinar sponsored by Data Sciences International, Dr. Marcio Furtado presents his research highlighting the importance of anomalous EEG detection to study experimental epilepsy and assess the efficacy of potential anticonvulsants and neuroprotectants. He also discusses why continuous EEG monitoring at a high sampling rate is critical to properly detect seizures and how to effectively deal with large telemetry data sets.
Watch this webinar to learn:
- Why neural hyper-synchronization (seizure activity) can result in permanent brain damage
- Tips for organizing, standardizing, and batch processing large data sets
- What features can be extracted from large EEG data sets
- Why inadequate sampling rates can lead to signal aliasing and how to avoid it
- How telemetry can be used to continuously monitor EEG and assess seizure activity in animal models of epilepsy
Sleep quality prediction in caregivers using physiological signalsReza Sadeghi
The presentation slides of the following paper:
R. Sadeghi, T. Banerjee, J.C. Hughes, L.W. Lawhorne, Sleep quality prediction in caregivers using physiological signals, Computers in Biology and Medicine (2019), doi:https://doi.org/10.1016/j.compbiomed.2019.05.010.
Optogenetics is a technique developed in 2006 that uses light to control neurons by inserting light-sensitive ion channel genes into brain cells. It works by using channelrhodopsin genes to excite neurons or halorhodopsin genes to inhibit neurons when light hits the nerve cell. This allows precise activation or stopping of specific neuron groups with high temporal resolution. Optogenetics offers potential treatment for conditions like anxiety, addiction, chronic pain, and sleep disorders by providing a less invasive way to stimulate or inhibit neurons compared to electrical methods. However, challenges include introducing foreign genes into the brain and technical issues like fiber optics posing infection risks or requiring heavy batteries.
This document provides an overview of neuroimaging techniques used in psychiatry. It discusses various structural and functional neuroimaging methods including CT, MRI, fMRI, SPECT, PET, DTI, and MRS. CT and MRI provide structural images while fMRI, SPECT, PET, and MRS assess brain function by measuring activity, blood flow, and metabolite levels. Neuroimaging has improved understanding of psychiatric conditions and informed research on the pathophysiology of disorders.
This document discusses the potential health risks of LED lighting, particularly from exposure to blue light at night. It summarizes research finding links between light at night and increased risks of breast cancer, diabetes, and sleep disorders. Studies suggest that blue light can disrupt circadian rhythms by suppressing melatonin production. While direct health effects of LEDs are unclear, late-evening exposure to light may impact circadian rhythms. Variables like light spectrum, intensity, duration and timing of exposure are important. High color temperature white LEDs contain more short wavelengths of blue light, which can be detrimental to health. Younger and older individuals may be more susceptible to circadian disruption from light at night.
Low Level Laser Therapy and Memory Enhancement: Effect of Different Energy DosesIJERD Editor
Short-term memory is the information we are currently aware of or thinking about. The amount of information that can be stored in short-term memory can vary. An often cited figure is plus or minus seven items, based on the results of a famous experiment on short-term memory. Use of various new techniques to enhance the training module certainly help the learning in college age population, but doesnot provide any solution to the biologically retarding memory due to stress and inflammation of the neurons of the brain. Our research aimed to study the effect different energy doses of Low Level Laser Therapy (LLLT) on memorizing capacity of the young population aged 20years to 30 years. For the purpose two equivalent tests of non-associated meaningful words were used. 106 subjects were divided into in Group A and Group B and each group took the “non-associated memory test” test, followed by Low Level Laser Therapytwice a week for four weeks. At the end of the 30thday an equivalent “non-associated memory test” post test was taken and the data was analyzed. The memory retention score of Group A was increase by 29.7% after 8 applications of LLLT. On the other hand group B showed 2% increase after 8 applications of LLLT. In conclusion low level laser therapy, when used with the correct frequency, powered density and dose can be very effective in increasing the working memory of the test individuals.
"The Future of Sleep with Neurotechnology" - Anant Sachetee (Rythm)Hyper Wellbeing
"The Future of Sleep with Neurotechnology" - Anant Sachetee (Rythm)
Delivered at the inaugural Hyper Wellbeing Summit, 14th November 2016, Mountain View, California.
For more information including details of subsequent events, please visit http://hyperwellbeing.com
The summit was created to foster a community around an emerging industry - Wellness as a Service (WaaS). Consumer technologies, in particular wearables and mobile, are powering a consumer revolution. A revolution to turn health and wellness into platform delivered services. A revolution enabling consumer data-driven disease risk reduction. A revolution extending health care past sick care towards consumer-led lifelong health, wellness and lifestyle optimization.
WaaS newsletter sign-up http://eepurl.com/b71fdr
@hyperwellbeing
Circadian Rhythm Enhancing Brain Synchronization and Cognitionijtsrd
Cognition is impaired in many neuropsychiatric disorders and the quality of life is severely affected. A key mechanism for sculpting communication patterns between large scale brain networks that underpin cognition and its breakdown in neuropsychiatric disorders is synchronous electrophysiological rhythms. According to a study, light has a wide range of effects on the synchronization of circadian rhythms with the external environment and it is found that light influences the urinary excretion of melatonin and controls sleep. Autonomic and neuroendocrine responses such as feedback regulation and the involvement of the immune system have also been shown to influence the circadian rhythm. There have been major advances in our understanding of the retinal photoreceptors mediating these non image forming light responses over the last two decades, as well as the neural pathways and molecular mechanisms that generate and energize circadian rhythms in the phase of the light dark LD cycle. Our understanding of the mechanisms by which lighting impacts cognitive processes, on the other hand, is more misleading. Lights effect on different cognitive processes is complex. Indirect effects may also arise due to disrupted circadian rhythm, in addition to the direct effects of light on consciousness. In studies that rely on various cognitive and sensory processes, different assays have been used, which can also contribute to variable outcomes. The physiological basis of these responses and the influence of various lighting environments on cognitive processes are summarized here, taking into account their effects on circadian rhythms, sleep and arousal. Uthirakumar Devaraj | Elumalai Balamurugan "Circadian Rhythm: Enhancing Brain Synchronization and Cognition" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-5 | Issue-6 , October 2021, URL: https://www.ijtsrd.com/papers/ijtsrd46394.pdf Paper URL : https://www.ijtsrd.com/biological-science/neurobiology/46394/circadian-rhythm-enhancing-brain-synchronization-and-cognition/uthirakumar-devaraj
This document discusses using audio-visual entrainment (AVE) to treat seasonal affective disorder (SAD). It provides background on SAD, noting it affects 6-20% of northern populations and has similar symptoms in other regions/contexts. Traditional treatments are light therapy and antidepressants. The document outlines a study applying 20Hz AVE to 74 SAD patients over 4 weeks, finding it reduced depression and anxiety symptoms more than a placebo session. AVE is proposed as an effective alternative or addition to light therapy for treating SAD.
Circadian rhythm sleep disorders (CRSD) are a family of sleep disorders affecting (among other bodily processes) the timing of sleep. People with circadian rhythm sleep disorders are unable to go to sleep and awaken at the times commonly required for work and school as well as social needs. They are generally able to get enough sleep if allowed to sleep and wake at the times dictated by their "body clocks". The quality of their sleep is usually normal unless they also have another sleep disorder.
My presentation deals with how circadian rhythm happens in human body and how alterations in circadian rhythm effects in different disorders.
Low-level laser therapy (LLLT) involves applying red or near-infrared light to injuries or lesions to improve wound and soft tissue healing and provide pain relief. LLLT works by stimulating cellular activity through absorption by chromophores like cytochrome c oxidase in the mitochondria. Clinical studies show LLLT can speed wound healing, reduce pain, and treat conditions like tendonitis. While LLLT dosage is challenging to define precisely due to variable beam shapes and densities, clinical results generally improve with higher total energy delivery.
POWER SPECTRAL ANALYSIS OF EEG AS A POTENTIAL MARKER IN THE DIAGNOSIS OF SPAS...ijbesjournal
The detection and diagnosis of various neurological disorders are performed using different medical
devices among which electroencephalogram (EEG) is one of the most cost effective technique. Though
significant progress had been made in the analysis of EEG for diagnosis of different neurological
disorders, yet detection of cerebral palsy (CP) is not quite clear. This study was performed to analyze the
EEG power spectrum density (PSD) of spastic CP and normal children to find if any significant EEG
patterns could be used for early detection of CP. Twenty children participated in this study out of which ten
were spastic CP and other ten were normal healthy children. EEG of all the participants was recorded
from C3 C4 and F3 F4 regions following montage 10-20 system. The artifact-free EEG signals of 15
minutes duration was extracted for spectral analysis using Fast Fourier Transformation (FFT) algorithm
in MATLAB and power density spectrum (PSD) was plotted. The PSD revealed high intensity power peak
at frequency of 50Hz and smaller at 100 Hz, which was consistent for all healthy subjects. In case of
spastic CP children, high intensity peak at 100Hz were prominent and smaller peak was observed at 50Hz.
The high intensity 100Hz peak observed in the PSD of spastic CP patients demonstrated that this tool can
be used for early detection of spastic CP.
The document is a research paper that examines how light deprivation affects mood regulation and depressive symptoms. It discusses several studies that investigated the effects of light deprivation on neurotransmitter levels, circadian rhythms, and depressive behaviors in rats and mice. The studies found that light deprivation disrupted circadian rhythms and caused neuronal death, especially of dopamine, norepinephrine and serotonin producing neurons. It also reduced dopamine synthesis and disrupted sleep, leading to increased depressive behaviors in the animal subjects. The document hypothesizes that light deprivation reduces dopamine replenishment in individuals prone to depressive mood symptoms.
Sulphur Plasma Light - A New Age of Light For Mankind!
Sulphur Plasma Lamps are the new revolutionary light source with the highest effectivity and a true full spectrum similar to that of sunlight.
This document summarizes a study that investigated whether melatonin treatment could modify depression-like and anxiety-like behaviors in a mouse model of seasonal affective disorder (SAD). Mice were exposed to short photoperiods to induce SAD-like behaviors and symptoms. Daily melatonin injections before lights off altered the expression patterns of circadian clock genes in the suprachiasmatic nucleus and genes related to serotonin neurotransmission in the dorsal raphe. Melatonin treatment also reduced depression-like behavior in forced swim tests. While melatonin did not strongly phase shift circadian rhythms, it increased the amplitude of oscillations in clock gene expression. The findings suggest modest adjustments to circadian rhythms from melat
This document provides an overview of a seminar presentation on radionuclide imaging. The presentation aims to explain radionuclide imaging, its history, indications, contraindications, advantages, disadvantages, and newer techniques like SPECT, PET, and PET-CT. It discusses the basics of radionuclide production and imaging, including the mechanisms, equipment, and applications of various nuclear medicine procedures like bone scans, lymphoscintigraphy, and salivary gland imaging.
Design and development of a method for detecting sleep roll-over counts usin...IJECEIAES
Sleep plays an important role as it helps human body to rejuvenate, boosts mental function and manage stress. Sleep is restorative function which enhances muscle growth, repairs tissues, maintains health and make physical appearance look or feel better. The lack of sleep in human body can increase the risk of diseases which are asthma, diabetes, depression. For healthy physiological function, sleep is essential and has strong relation to mental condition. Easy way of sleep management is considered for maintaining good mental health. Numerous scientists, doctors and researchers have proposed various ways to monitor sleep, some of those best tests are polysomnography test and actigraphy test. However, taking sleep test covering the whole body with wires and electrodes which is polysomnography test is uncomfortable for patients, and sensors used for different approaches like this are costly and often require overnight treatment and expert monitoring in clinics. Therefore, easy way of detecting roll-over movements which is convenient for patients to wear is proposed. Accelerometer ADXL335 sensor is taped on socks during sleep which is comfortable for patients to wear and do not cause any inconvenience during sleep. Algorithm is proposed to read the dataset and count the roll-over during the sleep based on threshold. Resulting the number of roll-over detected during a sleep period.
Near infrared spectroscopy for medical applications current status and future...skywalkerskywalker
This review discusses the use of near-infrared spectroscopy (NIRS) for medical applications. NIRS can be used to noninvasively measure oxygen levels in tissues due to NIR light's ability to penetrate the body. It has various applications including functional brain analysis, disease diagnosis, and monitoring of clinical laboratory tests. The review introduces recent advances in NIRS and its potential clinical uses such as measuring oxygen levels in the brain during tasks, detecting diseases, and analyzing biomolecules in the body.
Blue Light, Vision and the Eye White paper LZAL201016Dennis Loving
By developing an experimental framework to distinguish beneficial blue light rays from harmful ones, Essilor has effectively created a new field in photobiology research. Through a rigorous 4-year study conducted with the Paris Vision Institute using an in vitro cell model, Essilor identified for the first time the precise wavelength range within blue light - 415nm to 455nm centered at 435nm - that is most toxic to retinal pigment epithelium cells. This discovery paves the way for new protective lenses that can selectively filter this harmful light while allowing beneficial wavelengths to pass through, aiding in the prevention of age-related macular degeneration and other retinal diseases.
The document summarizes a student's research project examining the potential of the CB2 cannabinoid receptor as a target for neuroprotection in Parkinson's disease. The student conducted experiments showing that activating the CB2 receptor with a pharmacological agonist prevented neurodegeneration in an inflammation-driven rat model of Parkinson's. Preliminary analysis of human brain tissue also found microglial activation but was inconclusive about CB2 receptor expression. The student gained experience in laboratory techniques and contributed significantly to the project.
Similar to journal of endocrinology short wavelength light enhances cortisol awakening response in sleep-restricted adolescents (20)
This particular slides consist of- what is hypotension,what are it's causes and it's effect on body, risk factors, symptoms,complications, diagnosis and role of physiotherapy in it.
This slide is very helpful for physiotherapy students and also for other medical and healthcare students.
Here is the summary of hypotension:
Hypotension, or low blood pressure, is when the pressure of blood circulating in the body is lower than normal or expected. It's only a problem if it negatively impacts the body and causes symptoms. Normal blood pressure is usually between 90/60 mmHg and 120/80 mmHg, but pressures below 90/60 are generally considered hypotensive.
About this webinar: This talk will introduce what cancer rehabilitation is, where it fits into the cancer trajectory, and who can benefit from it. In addition, the current landscape of cancer rehabilitation in Canada will be discussed and the need for advocacy to increase access to this essential component of cancer care.
The best massage spa Ajman is Chandrima Spa Ajman, which was founded in 2023 and is exclusively for men 24 hours a day. As of right now, our parent firm has been providing massage services to over 50,000+ clients in Ajman for the past 10 years. It has about 8+ branches. This demonstrates that Chandrima Spa Ajman is among the most reasonably priced spas in Ajman and the ideal place to unwind and rejuvenate. We provide a wide range of Spa massage treatments, including Indian, Pakistani, Kerala, Malayali, and body-to-body massages. Numerous massage techniques are available, including deep tissue, Swedish, Thai, Russian, and hot stone massages. Our massage therapists produce genuinely unique treatments that generate a revitalized sense of inner serenely by fusing modern techniques, the cleanest natural substances, and traditional holistic therapists.
At Apollo Hospital, Lucknow, U.P., we provide specialized care for children experiencing dehydration and other symptoms. We also offer NICU & PICU Ambulance Facility Services. Consult our expert today for the best pediatric emergency care.
For More Details:
Map: https://cutt.ly/BwCeflYo
Name: Apollo Hospital
Address: Singar Nagar, LDA Colony, Lucknow, Uttar Pradesh 226012
Phone: 08429021957
Opening Hours: 24X7
Michigan HealthTech Market Map 2024. Includes 7 categories: Policy Makers, Academic Innovation Centers, Digital Health Providers, Healthcare Providers, Payers / Insurance, Device Companies, Life Science Companies, Innovation Accelerators. Developed by the Michigan-Israel Business Accelerator
DECODING THE RISKS - ALCOHOL, TOBACCO & DRUGS.pdfDr Rachana Gujar
Introduction: Substance use education is crucial due to its prevalence and societal impact.
Alcohol Use: Immediate and long-term risks include impaired judgment, health issues, and social consequences.
Tobacco Use: Immediate effects include increased heart rate, while long-term risks encompass cancer and heart disease.
Drug Use: Risks vary depending on the drug type, including health and psychological implications.
Prevention Strategies: Education, healthy coping mechanisms, community support, and policies are vital in preventing substance use.
Harm Reduction Strategies: Safe use practices, medication-assisted treatment, and naloxone availability aim to reduce harm.
Seeking Help for Addiction: Recognizing signs, available treatments, support systems, and resources are essential for recovery.
Personal Stories: Real stories of recovery emphasize hope and resilience.
Interactive Q&A: Engage the audience and encourage discussion.
Conclusion: Recap key points and emphasize the importance of awareness, prevention, and seeking help.
Resources: Provide contact information and links for further support.
This particular slides consist of- what is Pneumothorax,what are it's causes and it's effect on body, risk factors, symptoms,complications, diagnosis and role of physiotherapy in it.
This slide is very helpful for physiotherapy students and also for other medical and healthcare students.
Here is a summary of Pneumothorax:
Pneumothorax, also known as a collapsed lung, is a condition that occurs when air leaks into the space between the lung and chest wall. This air buildup puts pressure on the lung, preventing it from expanding fully when you breathe. A pneumothorax can cause a complete or partial collapse of the lung.
Chandrima Spa Ajman is one of the leading Massage Center in Ajman, which is open 24 hours exclusively for men. Being one of the most affordable Spa in Ajman, we offer Body to Body massage, Kerala Massage, Malayali Massage, Indian Massage, Pakistani Massage Russian massage, Thai massage, Swedish massage, Hot Stone Massage, Deep Tissue Massage, and many more. Indulge in the ultimate massage experience and book your appointment today. We are confident that you will leave our Massage spa feeling refreshed, rejuvenated, and ready to take on the world.
Visit : https://massagespaajman.com/
Call : 052 987 1315
PET CT beginners Guide covers some of the underrepresented topics in PET CTMiadAlsulami
This lecture briefly covers some of the underrepresented topics in Molecular imaging with cases , such as:
- Primary pleural tumors and pleural metastases.
- Distinguishing between MPM and Talc Pleurodesis.
- Urological tumors.
- The role of FDG PET in NET.
We are one of the top Massage Spa Ajman Our highly skilled, experienced, and certified massage therapists from different corners of the world are committed to serving you with a soothing and relaxing experience. Luxuriate yourself at our spas in Sharjah and Ajman, which are indeed enriched with an ambiance of relaxation and tranquility. We could confidently claim that we are one of the most affordable Spa Ajman and Sharjah as well, where you can book the massage session of your choice for just 99 AED at any time as we are open 24 hours a day, 7 days a week.
Visit : https://massagespaajman.com/
Call : 052 987 1315
The facial nerve, also known as cranial nerve VII, is one of the 12 cranial nerves originating from the brain. It's a mixed nerve, meaning it contains both sensory and motor fibres, and it plays a crucial role in controlling various facial muscles, as well as conveying sensory information from the taste buds on the anterior two-thirds of the tongue.
Unlocking the Secrets to Safe Patient Handling.pdfLift Ability
Furthermore, the time constraints and workload in healthcare settings can make it challenging for caregivers to prioritise safe patient handling Australia practices, leading to shortcuts and increased risks.
2024 HIPAA Compliance Training Guide to the Compliance OfficersConference Panel
Join us for a comprehensive 90-minute lesson designed specifically for Compliance Officers and Practice/Business Managers. This 2024 HIPAA Training session will guide you through the critical steps needed to ensure your practice is fully prepared for upcoming audits. Key updates and significant changes under the Omnibus Rule will be covered, along with the latest applicable updates for 2024.
Key Areas Covered:
Texting and Email Communication: Understand the compliance requirements for electronic communication.
Encryption Standards: Learn what is necessary and what is overhyped.
Medical Messaging and Voice Data: Ensure secure handling of sensitive information.
IT Risk Factors: Identify and mitigate risks related to your IT infrastructure.
Why Attend:
Expert Instructor: Brian Tuttle, with over 20 years in Health IT and Compliance Consulting, brings invaluable experience and knowledge, including insights from over 1000 risk assessments and direct dealings with Office of Civil Rights HIPAA auditors.
Actionable Insights: Receive practical advice on preparing for audits and avoiding common mistakes.
Clarity on Compliance: Clear up misconceptions and understand the reality of HIPAA regulations.
Ensure your compliance strategy is up-to-date and effective. Enroll now and be prepared for the 2024 HIPAA audits.
Enroll Now to secure your spot in this crucial training session and ensure your HIPAA compliance is robust and audit-ready.
https://conferencepanel.com/conference/hipaa-training-for-the-compliance-officer-2024-updates
2. 2 International Journal of Endocrinology
7 hours [19]. Consistently, Späth-Schwalbe et al. reported
higher releases of cortisol after long sleep durations as com-
pared to short sleep, which was measured using polysomnog-
raphy (PSG) [20]. Griefahn and Robens confirmed these
results by showing that total sleep time, as measured by PSG,
was positively correlated with CAR in evening types after
sleep during the nighttime but not after sleep during the
daytime [21].
Morning exposure to polychromatic (white) light has
been shown to enhance CAR in humans who were not sleep
restricted. Leproult et al. showed that morning exposure
(05:00–08:00 h) to a bright light (5,000 lux of a white light at
participants’ corneas) resulted in a 50% increase in cortisol
levels compared to remaining in dim light (<150 lux).
Afternoon exposure (13:00–16:00 h) to the same light did
not impact cortisol levels [22]. Scheer and Buijis also showed
an effect of morning light exposure, but not evening light
exposure, on cortisol levels and on heart rate. A 1-hour
exposure to 800 lux of white light in the morning resulted
in a 35% increase in cortisol levels compared to dim light.
Evening cortisol was not affected by light exposure [23].
More recently, Jung et al. showed an acute suppressive effect
on cortisol levels following bright light exposure (10,000 lux
of white light for 6.5 hours) during the biological night and
morning, close to the subjects’ habitual wakeup times [24].
The present paper represents a subanalysis of a larger
unpublished study investigating the impact of evening and
morning short-wavelength light on performance and on
biomarkers in sleep-restricted adolescents. Here, we report
the impact 40 lux (0.401 W/m2) of a 470-nm peaking (blue)
light on CAR in sleep-restricted adolescents, aged 12–
17 years. We hypothesized that the 470-nm light would
significantly enhance CAR in sleep-restricted adolescents
compared to dim light exposure.
In real-life situations, adolescents can be chronically
sleep deprived because of their inability to fall asleep early
and their fixed wakeup times during school days. Based on
the literature, it is reasonable to hypothesize that CAR in
adolescents may be diminished as a result of the reduced total
sleep time; therefore, an enhancement in CAR by morning
light has the potential to better prepare sleep-restricted
adolescents for daily environmental stressors.
2. Methods
2.1. Participants. Eighteen adolescents, nine females, mean
± standard deviation (SD) age 13.4 ± 1.0 years, and nine
males, average ± SD age 16.5 ± 0.7 years, were recruited
to participate in the study (mean age ± SD 15 ± 1.8
years). All subjects signed an assent form and parents signed
a consent form approved by the Rensselaer Polytechnic
Institute Institutional Review Board and were paid for their
participation. Participants were divided into two groups
based on gender, and each group of nine participants came to
the laboratory for three overnight sessions spaced one week
apart. All participants completed a Munich Chronotype
Questionnaire (MCTQ) [25]. Mean ± SD chronotypes of
the female and male participants were 3.2 ± 0.4 and 2.7 ±
1.7, respectively (overall mean ± SD chronotype was 2.9 ±
Table 1: Chronotypes of each participant.
Subject Age (years) Chronotype
Females
1 13 3
2 12 3
3 12 3
4 13 4
5 15 3
6 14 3
7 14 4
8 14 3
9 14 3
Female mean ± SD 13.4 ± 1.0 3.2 ± 0.4
Males
10 17 1
11 17 1
12 17 1
13 16 4
14 15 4
15 17 4
16 17 3
17 16 5
18 17 1
Male mean ± SD 16.5 ± 0.7 2.7 ± 1.7
mean average ± SD 15 ± 1.8 2.9 ± 1.2
1.2). Chronotypes for each participant are shown in Table 1.
Participants were asked to keep a regular sleep/wake schedule
during the three weeks of the study (bedtimes no later than
23:00 h and wake times no later than 07:00 h) and were asked
to keep a daily sleep log. None of the participants reported
having sleep problems. All participants wore a Dimesimeter
mounted on a wrist band to measure light exposures and to
verify the regularity of their activity-rest periods during the
three weeks of the study [26]. The Dimesimeter is a small,
unobtrusive, and user friendly research tool for collecting
personal light exposures and activity levels over multiple days
and nights. The Dimesimeter is calibrated in terms of the
spectral sensitivities of the visual and circadian systems [26].
Based on the sleep logs and on the Dimesimeter data, all
participants complied with the sleep schedules.
2.2. Lighting Conditions. Special long-wavelength (red) and
short-wavelength (blue) light goggles were constructed for
the study. Four long-wavelength (λmax ≈ 630 nm) or four
short-wavelength (λmax ≈ 470 nm), light emitting diodes
(LEDs) were mounted on the lenses of transparent goggles.
The long-wavelength, red light goggles were used in the
evening, as detailed below. For both spectra, one LED was
mounted above and one was mounted below the center each
of the two lenses. To limit the luminance of the sources, and
thus minimize the risk of blue light hazard [27], a small
diffuser was placed in front of each LED. The light goggles
used a 9-V battery, which was removed from a controller box
when the goggles were not being used.
3. International Journal of Endocrinology 3
Table 2: Lighting scenarios presented to all 18 participants in a counterbalanced manner.
Lighting scenarios
Evening Morning
Dim Light Session <5 lux at the cornea from an incandescent light source <5 lux at the cornea from an incandescent light source
Light Session 1
40 lux(0.182 W/m2) of long-wavelength, red light
(λmax ≈ 630 nm)
40 lux(0.401 W/m2) of short-wavelength, blue light
(λmax ≈ 470 nm)
Light Session 2 <5 lux at the cornea from an incandescent light source
40 lux(0.401 W/m2) of short-wavelength, blue light
(λmax ≈ 470 nm)
Light goggles were calibrated prior to each experimen-
tal session using a spectrometer (Oriel Multispec model
77400 with an Oriel Instaspec IV CCD detector). An
opal diffuser was fixed over the fiber-optic input to the
spectrometer to produce the needed spatial response for
measuring irradiance. The spectrometer was first calibrated
for wavelength accuracy using four visible spectrum mercury
emission lines from a cool-white fluorescent lamp (GE
F15T8-CW) and the 632.8 nm emission line from a helium-
neon laser (Melles Griot, model 05-LHP-141). The output
of the spectrometer was calibrated for spectral irradiance
(W/(m2·nm)) from readings taken at a prescribed distance
(1.00 m) from a tungsten-halogen lamp standard (lamp
no. 12, 75 W Q/CL) traceable to the National Institute of
Standards and Technology (NIST). Each pair of goggles was
then placed in a measurement jig that held it approximately
2 cm (the typical distance between a participant’s cornea
and the goggle lenses) from the spectrometer input diffuser.
Spectral irradiance levels were iteratively measured to reach
40 lux (0.401 W/m2 for 470 nm and 0.182 W/m2 for 630 nm).
This same procedure was used for both the short- and long-
wavelength goggles. Spectral irradiances were equated for
photopic illuminance because there is no known model for
the spectral sensitivity of the adrenal gland to light. Our
starting point for research was to equate the short- and the
long-wavelength lights for equal “visual” effectiveness.
2.3. Procedures. The study was run over the course of
three overnight sessions, at least 1 week apart. The three
experimental sessions differed in terms of the light exposure
scenarios experienced during the evening prior to sleeping in
the laboratory and during the morning after awaking. Table 2
shows the three lighting scenarios that were presented to all
18 participants. Light Sessions 1 and 2 differed only in their
evening light exposures (exposure to either dim or long-
wavelength light), but not in their morning light exposures
(always short-wavelength light exposure). Long-wavelength
light exposure in the evening was used because it does not
phase shift the circadian clock, but it may increase alertness,
and therefore, improve performance at night [28].
Participants arrived at the laboratory at 22:30 h after
eating a normal meal at home. The participants in Light
Session 1 wore the long-wavelength light goggles starting
at 22:45 h and continued wearing them until the end of all
testing at 01:15 h. All participants were asked to perform
two 60-minute performance tests twice, starting at 23:00 h
and 00:15 h. One performance test was measured on the
Multi-Attribute Task Battery (MAT) for Human Operator
Workload and Strategic Behavior Research software program
(NASA COSMIC collection, Open Channel Foundation).
The 54-minute MAT Battery was comprised of (i) a
monitoring task, (ii) a tracking task, and (iii) a resource
management task. The second set of tests included short-
term memory and reaction times tests that took about 6
minutes to complete. Although our short-term performance
tests showed a slight improvement with morning short-
wavelength light, none of the differences reached statistical
significance, and those results will not be further discussed
here.
At the end of the evening sessions (01:15 h), participants
were given a prescribed, fixed meal. It is important to note
that, although a meal in the middle of the night may be
a zeitgeber, the same procedure was repeated in all three
weeks of the experiment; therefore, this variable was constant
throughout the experiment. Participants then retired to a
sleeping area in the laboratory at 01:30 h and were awakened
at 06:00 h Sunday morning; the opportunity to sleep in
a dark room was 4.5 hours. Upon awakening at 06:00 h,
saliva samples were collected in dim light, while participants
were still on their mattresses. Soon after the first sample
collection, they were asked to remain awake in bed and were
presented either the short-wavelength light or the dim light.
Participants were allowed to engage in conversations and
to quietly listen to music. In every experimental week, 6
participants were presented with the short-wavelength light
while 3 participants remained in dim light. Saliva samples
were obtained every 20 minutes from waking at 06:00 h until
07:20 h, at which time they had a 10-minute break. A total
of 5 samples were collected while participants remained on
their mattresses. After the break, participants began the 60-
minute performance tests at 07:30 h. Two additional samples
were collected just before and just after they performed the
tests, and these samples were not included in the analyses
because the tests themselves could have influenced cortisol
levels. The experiment ended at 08:30 h.
2.4. Sample Collection and Data Analyses. Saliva samples
were collected for subsequent concentration level assess-
ments of cortisol using the Salivette system from Alpco
Diagnostics (Salem, NH, USA). This system consists of
a centrifuge vessel with a suspended insert in which a
cotton swab is placed. To collect the saliva, the cap was
removed and the participants put the tube against the lips
to take the cotton swab into the mouth without touching
4. 4 International Journal of Endocrinology
it with the fingers. The participants then chewed the swab
to impregnate it with saliva. Between 1-2 mL of saliva are
required for the analyses. After chewing the cotton, the
participants then spit the cotton back into the suspended
insert, and the cap on the tube was replaced. The vessels
containing the suspended saliva-impregnated cotton swabs
were then spun in a centrifuge at 3500 rotations per minute
(1000 ×g) for five minutes, causing the saliva to collect at
the bottom of the centrifuge vessel. Saliva samples were
then frozen for transport to a laboratory for cortisol assays
(Pharmasan, Osceola, WI, USA). The limit of detection
for the cortisol assay was 0.0036 μg/dL and the intra- and
interassay coefficients of variability were 3.6% and 6.4%,
respectively.
To ascertain consistency in results, three analyses were
performed using the cortisol levels data. The first one was
used to examine the impact of light on CAR. For this analysis,
CAR was calculated as the difference between the cortisol
level at 20 and at 40 minutes relative to the time of awaking.
Two-tailed, paired Student’s t-tests were used to determine
whether CAR under Light Sessions 1 and 2 were significantly
different from those obtained during the Dim Light Session.
For the second analysis, the area under the curve (AUC)
with respect to the increase in cortisol (i.e., with reference
to the postawakening, first sample collected in dim light)
was calculated based on the method described by Pruessner
et al. [29]. We used the unnormalized data and included in
the calculations the postawakening samples (always collected
in dim light) and the samples collected at 20, 40, 60, and
80 minutes postawakening (collected under one of the three
lighting conditions). Two-tailed, paired Student’s t-tests were
used to compare the AUC values in the Dim Light Session to
those in Light Sessions 1 and 2.
For the third analysis, cortisol levels for each participant
were normalized to their 06:00 h data point (collected
in dim light) for each session. This normalization was
performed to account for any week-to-week variability in the
postawakening cortisol levels. Based on Clow et al. [12], we
had no reason to believe that the first sample collected in dim
light upon awakening would be different between weeks, and
individual differences were not of interest here.
A three (lighting sessions) by four (sample times) re-
peated measures analysis of variance (ANOVA) was per-
formed on the normalized data using samples collected at
20, 40, 60, and 80 minutes postawakening. Two-tailed, paired
Student’s t-tests were performed to examine the main effects
and interactions. When applicable, a Bonferroni correction
was applied to the multiple t-test comparisons. All statistical
analyses were performed using PASW Statistics 18.0.
3. Results
Results from the first analysis showed that CARs at 20
minutes were significantly greater in Light Sessions 1 and
2 than in the Dim Light Session (t(17) = 2.3, P = 0.04
and t(17) = 2.8, P = 0.01, resp.). The mean ± standard
error of the mean (SEM) CAR (defined as the difference in
cortisol levels at waking and at 20 minutes post-awakening)
Dim Light Session Light Session 1 Light Session 2
Total
morning
cortisol
levels
∗
0
0.2
0.4
0.6
0.8
1
1.2
Figure 1: Total morning cortisol levels during the 80 minutes of
data collection [(area under the curve (AUC)] were lower during
dim light than during blue light exposure. Although the AUC was
greater during blue light exposures than during the Dim Light
Session, the difference was statistically significant only for the
second session. Shown are the mean ± SEM total cortisol levels
(AUC for 80 minutes) for each experimental condition.
were 0.14 ± 0.03μg/dL (3.9 ± 0.8 nmol/L) for the Dim Light
Session, 0.23 ± 0.04μg/dL (6.4 ± 1.2 nmol/L) for Light
Session 1, and 0.24 ± 0.03 μg/dL (6.5 ± 0.9 nmol/L) for Light
Session 2. CARs at 40 minutes after awakening were not
significantly greater in Light Sessions 1 and 2 compared to
CARs at 40 minutes in the Dim Light Session (t(17) =
1.4, P = 0.17 and t(17) = 1.9, P = 0.07, resp.). Mean ±
SEM CARs at 40 minutes after awakening (defined as the
difference in cortisol levels at waking and at 40 minutes post-
awakening) were 0.15± 0.06μg/dL (4.2± 1.6 nmol/L) for the
Dim Light Session, 0.24 ± 0.06μg/dL (6.6± 1.6 nmol/L) for
Light Session 1, and 0.29 ± 0.06 μg/dL (7.9 ± 1.8 nmol/L) for
Light Session 2.
Figure 1 shows the mean ± SEM total cortisol levels
during the 80-minute data collection period (AUC) for each
experimental condition. The two-tailed, paired Student’s t-
tests revealed a significantly greater AUC for Light Session
2 than for the Dim Light Session (t(17) = 2.3, P = 0.04).
The AUC for Light Session 1 was greater, but not significantly
different, than the AUC for the Dim Light Session (t(17) =
1.5, P = 0.16). The mean ± SEM AUC was 0.35 ± 0.2μg/dL
(9.6 ± 5.5 nmol/L) for the Dim Light Session, 0.58 ±
0.2μg/dL for Light Session 1 (16 ± 5.5 nmol/L), and 0.78 ±
0.8μg/dL for Light Session 2 (21.5 ± 5.5 nmol/L).
Figure 2 shows the normalized mean ± SEM cortisol
levels for each lighting scenario at each sample collection
time. The ANOVA revealed a significant main effect of
lighting session (F2,34 = 4.5; P = 0.02), a significant main
effect of time (F3,51 = 8.7, P < 0.0001), and a significant
interaction between the variables (F6,102 = 2.4, P = 0.03).
As with the AUC, the two-tailed, paired Student’s t-tests
revealed that, compared to the Dim Light Session, there
was a significant increase in cortisol levels in response to
light during Light Session 2 (t(17) = 2.5, P = 0.02), but
not during Light Session 1 (t(17) = 1.5, P = 0.1). Based
upon the significant interaction, the post hoc, two-tailed,
5. International Journal of Endocrinology 5
0
0.5
1
1.5
2
2.5
3
06:00 06:20 06:40 07:00 07:20
Dim Light Session
Light Session 2
Light Session 1
Time
Normalized
cortisol
levels
∗
∗
∗
∗
Figure 2: Normalized morning cortisol levels during the Dim
Light Session and during the two blue light exposure sessions.
All data were normalized to levels gathered at the first, common
experimental sampling time of 6:00 AM, which was the time
of awakening. Shown are the mean ± SEM normalized cortisol
levels for each experimental condition and sample collection time;
normalized cortisol levels during blue light exposures that were
significantly different than those during dim light are indicated with
asterisks.
paired Student’s t-tests also revealed that cortisol levels for
the Dim Light Session were significantly lower than those
under Light Session 2 at 20 minutes after awakening (t(17) =
2.7, P = 0.01), 40 minutes after awakening (t(17) = 2.4, P =
0.03), 60 minutes after awakening (t(17) = 2.4, P = 0.03),
and 80 minutes after awakening (t(17) = 2.5, P = 0.02).
None of the comparisons between cortisol levels for the Dim
Light Session and Light Session 1 were statistically significant
(t(17) = 2.1, P = 0.06 at 20 minutes after awakening, t(17)
= 1.6, P = 0.1 at 40 minutes after awakening, t(17) = 1.3,
P = 0.2 at 60 minutes after awakening, and t(17) = 0.5,
P = 0.6 at 80 minutes after awakening).
4. Discussion
The impact of morning retinal light exposures on CAR in
subjects who did not undergo sleep restriction has been
demonstrated previously [22, 23]. The present results extend
those previously published by demonstrating that short-
wavelength light exposures upon awakening increase CAR
and AUC in sleep-restricted adolescents.
Our results are not consistent with those from Jung
et al., who showed a decrease in morning cortisol levels
after light exposure [24]. The present study investigated the
impact of 470-nm light on CAR, while the study by Jung
et al. investigated the impact of a polychromatic (white)
light on the ascending and descending segments of the
cortisol rhythm. Moreover, the very different experimental
protocols employed in the two studies may contribute to
these different results. Jung et al. kept participants in the
laboratory for several days, while our participants came
to the laboratory once a week for an overnight session.
They exposed participants to 10,000 lux of a white light
(4100 K fluorescent lamp) for 6.5 hours, while we exposed
our participants to 40 lux of a 470-nm light for 80 minutes.
Our participants, although sleep restricted, received the light
exposure upon awaking from a 4.5 hr sleep opportunity,
while participants in the Jung et al. experiment had been
awake for a few hours prior to the time when CAR would
have occurred if the subjects had been asleep [24]. It is known
that CAR is highly correlated with waking, and it may be that
the timing of sleep and waking modulates the impact of light
on CAR.
It was expected that cortisol levels in Light Sessions 1
and 2 would be similar because the experimental conditions
presented to the participants were the same in the mornings.
Interestingly, the higher cortisol levels in Light Session 2 than
in Light Session 1 may have been due to the differences in
the previous night light exposures, namely, subjects were
exposed to long-wavelength light and to dim light the
evening before Light Sessions 1 and 2, respectively. It is
also not known why the variance in Light Session 2 was
greater than in Light Session 1. As mentioned above, long-
wavelength light in the evening was used because it was
not expected to phase shift the circadian clock, but it was
hypothesized to increase performance because of its alerting
effects. It is known that the response of the pineal gland will
be modulated by prior light exposure [30, 31] but nothing
is known about the adaptation of the adrenal gland to
prior light exposure. Future studies should be performed to
directly investigate if evening long-wavelength light (which is
not expected to impact circadian phase) can modulate CAR
to light.
From the present results, it is not possible to determine
whether the melatonin pathway was involved in the enhanced
CAR response to short-wavelength light. Evidence that
light in the middle of the night can impact cortisol levels
via pathways other than melatonin suppression has been
demonstrated [32]. It would be interesting to investigate
if long-wavelength light can also enhance CAR or if the
mechanisms by which light impacts the adrenal gland are
different at different times of the night (i.e., middle of the
night versus morning). In other words, the SCN may simply
serve as a gating mechanism for the adrenal response to light
at different times of the day [33]. In fact, studies have linked
changes (both increases and decreases) in adrenal sensitivity
to adrenocorticotropic hormone with time of day and the
SCN [34–36]. Consistent with the idea that the sensitivity
of the adrenal gland to light may change over the course of
the day, Leproult et al. showed that morning light increased
cortisol levels, but evening light did not [22].
Previous studies have suggested that there is a relation-
ship between CAR and chronotypes. Morning chronotypes
were shown to have higher CAR than evening chronotypes
[37]. Our post hoc analyses did not show any relationship
between CAR and chronotypes, nor did it show any age and
gender differences in light responses. This lack of relationship
6. 6 International Journal of Endocrinology
between chronotypes and CAR may be because the majority
of our subjects reported being a 3 or 4 on the MCTQ
(n = 13), while 4 subjects reported being a 1 and one
subject reported being a 5. Further studies with a larger
sample size should be performed to specifically investigate
how chronotypes, age, and gender may differentially impact
the effect of short-wavelength light on CAR.
5. Conclusions
The present results are the first to show that 40 lux of
short-wavelength (blue) light enhances CAR in adolescents
who were restricted from sleep for one night (with 4.5
hours allowed in bed). An enhancement of CAR in humans
by morning light exposure, especially in adolescents who
tend to be sleep-deprived, may be important to “stimulate”
the body when it is time for it to be active and, thus,
prepare adolescents for any environmental stress they might
experience [38]. In addition, data presented here tentatively
suggest that reduced evening light exposures may also
influence CAR. Further studies should be performed to
confirm these findings.
Acknowledgments
Sharp Laboratories of America provided funding for this
study but was not involved in the design of the experiment,
data analyses, nor paper writing. Ibrahim Sezan and Gary
Feather of Sharp Laboratories of America are acknowledged
for their support. Barbara Plitnick, Brittany Wood, Robert
Hamner, Terry Klein, Dennis Guyon, and Ines Martinovic
of the Lighting Research Center are acknowledged for their
technical and editorial support.
References
[1] R. Y. Moore, “Circadian rhythms: basic neurobiology and clin-
ical applications,” Annual Review of Medicine, vol. 48, pp. 253–
266, 1997.
[2] G. C. Brainard, J. R. Hanifin, J. M. Greeson et al., “Action spec-
trum for melatonin regulation in humans: evidence for a novel
circadian photoreceptor,” Journal of Neuroscience, vol. 21, no.
16, pp. 6405–6412, 2001.
[3] M. S. Rea, M. G. Figueiro, J. D. Bullough, and A. Bierman, “A
model of phototransduction by the human circadian system,”
Brain Research Reviews, vol. 50, no. 2, pp. 213–228, 2005.
[4] H. R. Wright, L. C. Lack, and K. J. Patridge, “Light emitting
diodes can be used to phase delay the melatonin rhythm,”
Journal of Pineal Research, vol. 31, no. 4, pp. 350–355, 2001.
[5] C. Cajochen, M. Münch, S. Kobialka et al., “High sensitivity of
human melatonin, alertness, thermoregulation, and heart rate
to short wavelength light,” Journal of Clinical Endocrinology
and Metabolism, vol. 90, no. 3, pp. 1311–1316, 2005.
[6] M. G. Figueiro, J. D. Bullough, A. Bierman, C. R. Fay, and
M. S. Rea, “On light as an alerting stimulus at night,” Acta
Neurobiologiae Experimentalis, vol. 67, no. 2, pp. 171–178,
2007.
[7] C. Cajochen, C. Jud, M. Münch, S. Kobialka, A. Wirz-Justice,
and U. Albrecht, “Evening exposure to blue light stimulates
the expression of the clock gene PER2 in humans,” European
Journal of Neuroscience, vol. 23, no. 4, pp. 1082–1086, 2006.
[8] F. Halberg and R. B. Howard, “24 hour periodicity and exper-
imental medicine examples and interpretations,” Postgraduate
Medicine, vol. 24, no. 4, pp. 349–358, 1958.
[9] U. M. Nater, N. Rohleder, W. Schlotz, U. Ehlert, and C.
Kirschbaum, “Determinants of the diurnal course of salivary
alpha-amylase,” Psychoneuroendocrinology, vol. 32, no. 4, pp.
392–401, 2007.
[10] N. A. Nicolson, “Measurement of cortisol,” in Handbook of
Physiological Research Methods in Health Physiology, L. G.
Luecken and L. C. Gallo, Eds., Sage, 2008.
[11] J. C. Pruessner, O. T. Wolf, D. H. Hellhammer et al., “Free
cortisol levels after awakening: a reliable biological marker for
the assessment of adrenocortical activity,” Life Sciences, vol. 61,
no. 26, pp. 2539–2549, 1997.
[12] A. Clow, F. Hucklebridge, T. Stalder, P. Evans, and L. Thorn,
“The cortisol awakening response: more than a measure of
HPA axis function,” Neuroscience and Biobehavioral Reviews,
vol. 35, no. 1, pp. 97–103, 2010.
[13] A. Clow, L. Thorn, P. Evans, and F. Hucklebridge, “The Awak-
ening Cortisol Response: methodological Issues and Signifi-
cance,” Stress, vol. 7, no. 1, pp. 29–37, 2004.
[14] E. Fries, L. Dettenborn, and C. Kirschbaum, “The cortisol
awakening response (CAR): facts and future directions,”
International Journal of Psychophysiology, vol. 72, no. 1, pp. 67–
73, 2009.
[15] S. Sensi, V. Pace Palitti, and M. T. Guagnano, “Chronobiology
in endocrinology,” Annali dell’Istituto Superiore di Sanita, vol.
29, no. 4, pp. 613–631, 1993.
[16] F. E. Yates and J. Urquhart, “Control of plasma concentrations
of adrenocortical hormones,” Physiological Reviews, vol. 42,
no. 3, pp. 359–433, 1962.
[17] S. R. Kunz-Ebrecht, C. Kirschbaum, M. Marmot, and A.
Steptoe, “Differences in cortisol awakening response on work
days and weekends in women and men from the Whitehall II
cohort,” Psychoneuroendocrinology, vol. 29, no. 4, pp. 516–528,
2004.
[18] C. E. Gribbin, S. E. Watamura, A. Cairns et al., “The cortisol
awakening response (CAR) in 2- to 4-year-old children: effects
of acute nighttime sleep restriction, wake time, and daytime
napping,” Developmental Psychobiology, vol. 54, no. 4, pp. 412–
422, 2012.
[19] M. G. Figueiro and M. S. Rea, “Sleep opportunities and
periodic light exposures: impact on biomarkers, performance
and sleepiness,” Lighting Research and Technology, vol. 43, no.
3, pp. 349–369, 2011.
[20] E. Späth-Schwalbe, T. Schöller, W. Kern, H. L. Fehm, and J.
Born, “Nocturnal adrenocorticotropin and cortisol secretion
depends on sleep duration and decreases in association with
spontaneous awakening in the morning,” Journal of Clinical
Endocrinology and Metabolism, vol. 75, no. 6, pp. 1431–1435,
1992.
[21] B. Griefahn and S. Robens, “The cortisol awakening response:
a pilot study on the effects of shift work, morningness and
sleep duration,” Psychoneuroendocrinology, vol. 33, no. 7, pp.
981–988, 2008.
[22] R. Leproult, E. F. Colecchia, M. L’Hermite-Balériaux, and
E. Van Cauter, “Transition from dim to bright light in the
morning induces an immediate elevation of cortisol levels,”
Journal of Clinical Endocrinology and Metabolism, vol. 86, no.
1, pp. 151–157, 2001.
7. International Journal of Endocrinology 7
[23] F. A. J. L. Scheer and R. M. Buijs, “Light affects morning
salivary cortisol in humans,” Journal of Clinical Endocrinology
and Metabolism, vol. 84, no. 9, pp. 3395–3398, 1999.
[24] C. M. Jung, S. B. S. Khalsa, F. A. J. L. Scheer et al., “Acute effects
of bright light exposure on cortisol levels,” Journal of Biological
Rhythms, vol. 25, no. 3, pp. 208–216, 2010.
[25] T. Roenneberg, A. Wirz-Justice, and M. Merrow, “Life between
clocks: daily temporal patterns of human chronotypes,”
Journal of Biological Rhythms, vol. 18, no. 1, pp. 80–90, 2003.
[26] M. G. Figueiro, R. Hamner, A. Bierman, and M. S. Rea, “Com-
parisons of three practical field devices used to measure
personal light exposures and activity levels,” Lighting Research
and Technology, vol. 44, no. 2, 2012.
[27] J. D. Bullough, “The blue-light hazard: a review,” Journal of the
Illuminating Engineering Society, vol. 29, no. 2, pp. 6–14, 2000.
[28] M. G. Figueiro, A. Bierman, B. Plitnick, and M. S. Rea,
“Preliminary evidence that both blue and red light can induce
alertness at night,” BMC Neuroscience, vol. 10, article 105,
2009.
[29] J. C. Pruessner, C. Kirschbaum, G. Meinlschmid, and D.
H. Hellhammer, “Two formulas for computation of the
area under the curve represent measures of total hormone
concentration versus time-dependent change,” Psychoneu-
roendocrinology, vol. 28, no. 7, pp. 916–931, 2003.
[30] M. Hébert, S. K. Martin, C. Lee, and C. I. Eastman, “The
effects of prior light history on the suppression of melatonin
by light in humans,” Journal of Pineal Research, vol. 33, no. 4,
pp. 198–203, 2002.
[31] K. A. Smith, M. W. Schoen, and C. A. Czeisler, “Adaptation
of human pineal melatonin suppression by recent photic
history,” Journal of Clinical Endocrinology and Metabolism, vol.
89, no. 7, pp. 3610–3614, 2004.
[32] M. G. Figueiro and M. S. Rea, “The effects of red and blue
lights on circadian variations in cortisol, alpha amylase, and
melatonin,” International Journal of Endocrinology, vol. 2010,
Article ID 829351, 9 pages, 2010.
[33] A. Ishida, T. Mutoh, T. Ueyama et al., “Light activates the
adrenal gland: timing of gene expression and glucocorticoid
release,” Cell Metabolism, vol. 2, no. 5, pp. 297–307, 2005.
[34] S. R. Bornstein, W. C. Engeland, M. Ehrhart-Bornstein, and
J. P. Herman, “Dissociation of ACTH and glucocorticoids,”
Trends in Endocrinology and Metabolism, vol. 19, no. 5, pp.
175–180, 2008.
[35] R. M. Buijs, J. Wortel, J. J. Van Heerikhuize, and A. Kals-
beek, “Novel environment induced inhibition of corticos-
terone secretion: physiological evidence for a suprachiasmatic
nucleus mediated neuronal hypothalamo-adrenal cortex path-
way,” Brain Research, vol. 758, no. 1-2, pp. 229–236, 1997.
[36] R. M. Buijs, C. G. van Eden, V. D. Goncharuk, and A. Kalsbeek,
“The biological clock tunes the organs of the body: timing
by hormones and the autonomic nervous system,” Journal of
Endocrinology, vol. 177, no. 1, pp. 17–26, 2003.
[37] B. M. Kudielka, I. S. Federenko, D. H. Hellhammer, and S.
Wüst, “Morningness and eveningness: the free cortisol rise
after awakening in “early birds” and night owls,” Biological
Psychology, vol. 72, no. 2, pp. 141–146, 2006.
[38] National Sleep Foundation, “2006 Sleep in America poll:
Summary of findings,” http://www.sleepfoundation.org/sites/
default/files/2006 summary of findings.pdf.
8. Submit your manuscripts at
http://www.hindawi.com
Stem Cells
International
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
MEDIATORS
INFLAMMATION
of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Behavioural
Neurology
Endocrinology
International Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Disease Markers
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
BioMed
Research International
Oncology
Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Oxidative Medicine and
Cellular Longevity
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
PPAR Research
The Scientific
World Journal
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Immunology Research
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Journal of
Obesity
Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Computational and
Mathematical Methods
in Medicine
Ophthalmology
Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Diabetes Research
Journal of
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Research and Treatment
AIDS
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Gastroenterology
Research and Practice
Hindawi Publishing Corporation
http://www.hindawi.com Volume 2014
Parkinson’s
Disease
Evidence-Based
Complementary and
Alternative Medicine
Volume 2014
Hindawi Publishing Corporation
http://www.hindawi.com