The limbic system is a set of brain structures located around the thalamus that regulates emotion and memory. It includes structures like the hippocampus, amygdala, septal area, and hypothalamus. The hippocampus is involved in learning, recent memory, and arousal. The amygdala assigns emotional significance to experiences and mediates fear responses. The septal area is involved in pleasure, social bonding, and modulating aggression. Together these structures form a network that processes emotion and links it to other brain regions.
MRI and CT cross sectional anatomy and sulci gyri anatomy of brain.ppt pdfDr pradeep Kumar
This ppt is very important for radiology resident..Nice sectional anatomy of brain MRI as well as CT. Axial, saggital and coronal section of human brain .This presentation also include very good sectional anatomy of sulci and gyri of brain with labelling of all images . Must know for radiologist. Thanks.
Students are required to know the detailed anatomy of the cortex and also the lesions and their presentation in patients.Medicine in itself derived from a thorough understanding of the anatomy in the initial years of MBBS.Thus it is an iminantory part of this slideshare.
MRI and CT cross sectional anatomy and sulci gyri anatomy of brain.ppt pdfDr pradeep Kumar
This ppt is very important for radiology resident..Nice sectional anatomy of brain MRI as well as CT. Axial, saggital and coronal section of human brain .This presentation also include very good sectional anatomy of sulci and gyri of brain with labelling of all images . Must know for radiologist. Thanks.
Students are required to know the detailed anatomy of the cortex and also the lesions and their presentation in patients.Medicine in itself derived from a thorough understanding of the anatomy in the initial years of MBBS.Thus it is an iminantory part of this slideshare.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
These simplified slides by Dr. Sidra Arshad present an overview of the non-respiratory functions of the respiratory tract.
Learning objectives:
1. Enlist the non-respiratory functions of the respiratory tract
2. Briefly explain how these functions are carried out
3. Discuss the significance of dead space
4. Differentiate between minute ventilation and alveolar ventilation
5. Describe the cough and sneeze reflexes
Study Resources:
1. Chapter 39, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 34, Ganong’s Review of Medical Physiology, 26th edition
3. Chapter 17, Human Physiology by Lauralee Sherwood, 9th edition
4. Non-respiratory functions of the lungs https://academic.oup.com/bjaed/article/13/3/98/278874
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
2. LEARNING OBJECTIVES
• HISTORY OF LIMBIC SYSTEM
• BRIEF PHYSIOLOGICAL ANATOMY OF LIMBIC SYSTEM.
• FUNCTIONS OF LIMBIC SYSTEM.
• NEUROPSYCHIATRIC ASPECT OF LIMBIC SYSTEM
3. • THE TERM "LIMBIC" COMES FROM THE LATIN LIMBUS, FOR "BORDER" OR
"EDGE.
• REFERS TO A RING OF GRAY MATTER ON THE MEDIAL ASPECT OF THE
CEREBRAL HEMISPHERES.
• LIMBIC SYSTEM IS THE AREA OF THE BRAIN THAT REGULATES EMOTION
AND MEMORY.
• IT INCLUDES MANY STRUCTURES IN THE CEREBRAL PRE-CORTEX AND SUB-
CORTEX OF THE BRAIN .
• THE TERM HAS BEEN USED WITHIN PSYCHIATRYAND NEUROLOGY.
4. • THE LIMBIC SYSTEM, ALSO KNOWN AS THE PALEOMAMMALIAN CORTEX, IS
A SET OF BRAIN STRUCTURES LOCATED ON BOTH SIDES OF THE
THALAMUS, IMMEDIATELY BENEATH THE MEDIAL TEMPORAL LOBE OF THE
CEREBRUM PRIMARILY IN THE MIDBRAIN.
• THE ELEMENTS OF THE LIMBIC SYSTEM ARE PARTICULARLY CONCERNED
WITH MEMORY AND THE EMOTIONAL ASPECTS OF BEHAVIOUR, AND
PROVIDE AN AFFECTIVE OVERTONE TO CONSCIOUS EXPERIENCE AS WELL
AS AN INTERFACE WITH SUBCORTICAL AREAS SUCH AS THE
HYPOTHALAMUS, THROUGH WHICH WIDESPREAD PHYSIOLOGICAL
ACTIVITIES ARE INTEGRATED.
5. HISTORY
• PAUL BROCA : LIMBIC LOBE
• JAMES PAPEZ: PAPEZ CIRCUIT
• PAUL MAC LEAN: LIMBIC SYSTEM
6. LIMBIC LOBE 1878 PAUL BROCA
• IDENTIFIED MEDIAL SURFACE OF
CEREBRUM THAT ARE DIFFERENT
FROM THE REST OF CORTEX, CALLED
IT BORDER=LIMBIC LOBE
• CORTEX SURROUNDING CORPUS
CALLOSUM
• THOUGHT TO BE INVOLVED IN
OLFACTION
• THE CINGULATE AND
PARAHIPPOCAMPAL GYRI FORM THE
“LIMBIC LOBE,” A RIM OF TISSUE
LOCATED ALONG THE JUNCTION OF
7. COMPONENTS OF LIMBIC SYSTEM
• THE LIMBIC SYSTEM WAS DELINEATED BY JAMES PAPEZ IN 1937.
• THE PAPEZ CIRCUIT CONSISTS OF THE HIPPOCAMPUS, THE FORNIX,
THE MAMMILLARY BODIES, THE ANTERIOR NUCLEUS OF THE
THALAMUS, AND THE CINGULATE GYRUS.
• THE BOUNDARIES OF THE LIMBIC SYSTEM WERE SUBSEQUENTLY
EXPANDED TO INCLUDE THE AMYGDALA, SEPTUM, BASAL
FOREBRAIN, NUCLEUS ACCUMBENS, AND ORBITOFRONTAL CORTEX.
8.
9. PARTS OF LIMBIC SYSTEM
• LIMBIC CORTEX CONTAINING CINGULATE GYRUS &
PARAHIPPOCAMPAL GYRUS
• HIPPOCAMPAL FORMATION
• AMYGDALA
• SEPTAL AREA
• HYPOTHALAMUS & MAMILLARY BODIES
• ANTERIOR THALAMIC NUCLEUS
10.
11.
12. • UNLIKE THE SIGNALS OF THE SOMATOSENSORY, VISUAL, AND
AUDITORY SYSTEMS; OLFACTORY SIGNALS DO NOT PASS THROUGH
THE THALAMUS BUT PROJECT DIRECTLY TO THE FRONTAL LOBE
AND THE LIMBIC SYSTEM, ESPECIALLY THE PYRIFORM CORTEX.
• THE CONNECTIONS TO THE LIMBIC SYSTEM (AMYGDALA,
HIPPOCAMPUS, AND PYRIFORM CORTEX) ARE SIGNIFICANT.
13. • THE STRUCTURES OF HIGHER OLFACTORY PROCESSING IN
PHYLOGENETICALLY MORE PRIMITIVE ANIMALS HAVE EVOLVED IN
HUMANS INTO THE LIMBIC SYSTEM, THE CENTER OF THE
EMOTIONAL BRAIN AND THE GATE THROUGH WHICH EXPERIENCE IS
ADMITTED INTO MEMORY ACCORDING TO EMOTIONAL
SIGNIFICANCE.
• THE ELUSIVE BASIC ANIMAL DRIVES WITH WHICH CLINICAL
PSYCHIATRY CONSTANTLY GRAPPLES MAY THEREFORE, IN FACT,
ORIGINATE FROM THE ANCIENT CENTERS OF HIGHER OLFACTORY
PROCESSING.
14. • EMOTION DERIVES FROM BASIC DRIVES, SUCH AS FEEDING, SEX,
REPRODUCTION, PLEASURE, PAIN, FEAR, AND AGGRESSION, WHICH
ALL ANIMALS SHARE. THE NEUROANATOMICAL BASIS FOR THESE
DRIVES APPEARS TO BE CENTERED IN THE LIMBIC SYSTEM.
• THE LIMBIC SYSTEM APPEARS TO HOUSE THE EMOTIONAL
ASSOCIATION AREAS, WHICH DIRECT THE HYPOTHALAMUS TO
EXPRESS THE MOTOR AND ENDOCRINE COMPONENTS OF THE
EMOTIONAL STATE.
15. BLOOD SUPPLY OF LIMBIC SYSTEM
• THE MAIN VESSELS THAT SERVE MUCH OF THE LIMBIC SYSTEM ARE
THE ANTERIOR AND POSTERIOR CEREBRAL ARTERIES, THE ANTERIOR
CHOROIDAL ARTERY, AND BRANCHES ARISING FROM THE CIRCLE OF
WILLIS.
16. • TEMPORAL BRANCHES OF THE POSTERIOR CEREBRAL ARTERY SUPPLY THE
PARAHIPPOCAMPAL GYRUS.
• THE ANTERIOR CHOROIDAL ARTERY USUALLY ORIGINATES FROM THE INTERNAL
CAROTID ARTERY. THIS VESSEL SERVES THE CHOROID PLEXUS OF THE TEMPORAL
HORN, THE HIPPOCAMPAL FORMATION, PARTS OF THE AMYGDALOID COMPLEX, AND
ADJACENT STRUCTURES SUCH AS THE TAIL OF THE CAUDATE NUCLEUS, THE STRIA
TERMINALIS, AND THE SUBLENTICULAR AND RETROLENTICULAR LIMBS OF THE
INTERNAL CAPSULE.
• VESSELS SERVING HYPOTHALAMIC NUCLEI THAT ARE FUNCTIONALLY ASSOCIATED
WITH THE LIMBIC SYSTEM ORIGINATE FROM THE CIRCLE OF WILLIS. IN GENERAL,
ROSTRAL AREAS OF THE HYPOTHALAMUS ARE SERVED BY BRANCHES FROM THE
ANTERIOR COMMUNICATING ARTERY AND ANTERIOR CEREBRAL ARTERY; POSTERIOR
AREAS ARE SERVED BY BRANCHES FROM THE POSTERIOR COMMUNICATING ARTERY
17. HIPPOCAMPAL FORMATION
• LOCATION: FLOOR OF
TEMPORAL HORN OF THE
LATERAL VENTRICLE.
• CONSISTS OF DENTATE GYRUS,
HIPPOCAMPUS PROPER
(AMMON’S HORN) & SUBICULAR
COMPLEX.
• DENTATE GYRUS &
HIPPOCAMPUS ARE
TRILAMINATE STRUCTURE.
18. HIPPOCAMPUS PROPER
• BASED ON CYTOARCHITECTURE &
CONNECTIVITY, HIPPOCAMPUS IS
DIVIDED INTO 3 FIELDS: CA3, CA2,
CA1.
• PORTION OF THE HIPPOCAMPUS
ADJACENT TO CA3 & WITHIN ‘C’
CREATED BY GRANULE CELL LAYER OF
DENTATE GYRUS IS REFERRED AS HILUS
OF DENTATE GYRUS.
• WHITE MATTER ADJACENT TO
POLYMORPHIC LAYER OF
HIPPOCAMPUS IS KNOWN AS ALVEUS.
19. FUNCTIONS OF HIPPOCAMPUS
• LEARNING & RECENT MEMORY.
• AROUSAL RESPONSE.
• CHEMORECEPTOR- ENDOCRINE FUNCTION.
• HIPPOCAMPAL FUNCTION IS LOST IN ALZHEIMERS DISEASE.
• BILATERAL LESIONS CAUSE PROFOUNDLY IMPAIR RECENT MEMORY.
SOMETIMES PRODUCES KORSAKOFF’S SYNDROME.
• IT PLAYS A ROLE IN THE ORIGIN & PROPAGATION OF EPILEPTIC
SEIZURES.
20. MEMORY FORMATION
• THE COMPLEX PROCESSES OF MEMORY ENCODING IN THE
HIPPOCAMPUS AND RETRIEVAL OF EXPERIENCES FROM THE FRONTAL
LOBE INVOLVE TWO PROMINENT PATHWAYS: POLYSYNAPTIC AND
DIRECT PATHWAYS. THE POLYSYNAPTIC PATHWAY IS IMPORTANT
FOR THE SEMANTIC MEMORY (FACTS AND CONCEPTS), AND THE
DIRECT PATHWAY IS IMPORTANT FOR THE EPISODIC (RECOLLECTION
OF EVENTS) AND SPATIAL MEMORY (RECOGNITION).
21. Entorhinal cortex
Dentate gyrus
Pyramidal cells
CA3
Mossy fibres
Opposite hippocampus
via corpus callosum
CA1
Schaffer collateral pathways
Inferior temporal cortex, temporal pole, and prefrontal cortex
Process of Memory Formation
22. AMYGDALA
• LOCATION- IT IS A CLUSTER OF NUCLEI LOCATED AT MEDIAL
TEMPORAL LOBE, JUST ANTERIOR TO HIPPOCAMPAL FORMATION.
• SUBDIVISIONS- 1)BASOLATERAL COMPLEX, 2)CENTRAL AMYGDALOID
GROUP AND 3)OLFACTORY GROUP WITH CORTICAL AMYGDALOID
NUCLEI.
23. AMYGDALA
• THE AMYGDALA APPEARS TO BE A CRITICALLY IMPORTANT GATE
THROUGH WHICH INTERNAL AND EXTERNAL STIMULI ARE INTEGRATED.
INFORMATION FROM THE PRIMARY SENSES IS INTERWOVEN WITH
INTERNAL DRIVES, SUCH AS HUNGER AND THIRST, TO ASSIGN EMOTIONAL
SIGNIFICANCE TO SENSORY EXPERIENCES.
• THE AMYGDALA MAY MEDIATE LEARNED FEAR RESPONSES, SUCH AS
ANXIETY AND PANIC, AND MAY DIRECT THE EXPRESSION OF CERTAIN
EMOTIONS BY PRODUCING A PARTICULAR AFFECT. NEUROANATOMICAL
DATA SUGGEST THAT THE AMYGDALA EXERTS A MORE POWERFUL
INFLUENCE ON THE CORTEX, TO STIMULATE OR SUPPRESS CORTICAL
ACTIVITY, THAN THE CORTEX EXERTS ON THE AMYGDALA.
24. AMYGDALA
• PATHWAYS FROM THE SENSORY THALAMIC RELAY STATIONS
SEPARATELY SEND SENSORY DATA TO THE AMYGDALA AND THE
CORTEX, BUT THE SUBSEQUENT IMPACT OF THE AMYGDALA ON THE
CORTEX IS THE MORE POTENT OF THE TWO RECIPROCAL
CONNECTIONS.
• IN CONTRAST, DAMAGE TO THE AMYGDALA HAS BEEN REPORTED
TO ABLATE THE ABILITY TO DISTINGUISH FEAR AND ANGER IN
OTHER PERSONS’ VOICES AND FACIAL EXPRESSIONS. PERSONS WITH
SUCH INJURIES MAY HAVE A PRESERVED ABILITY TO RECOGNIZE
HAPPINESS, SADNESS, OR DISGUST.
26. AMYGDALA
Corticomedial Nuclear Group
Basolateral Medical Group
Central Nucleus
Olfactory System
Temporal Lobe
(associated with visual,
auditory, tactile senses)
rainstem: (viscerosensory relay
Nuclei: solitary nucleus and
Parbrachial nucleus)
Ventral amygdalofugal fibres
Septal nuclei hypothalamu
Dorsal medical thalamic nucle
Nucleus Accumbens
hypothalamus
Nuclei of ANS
Stria Terminalis
AFFERENTS EFFERENTS
27. FUNCTIONS OF AMYGDALA
• IT INTEGRATES INPUTS FROM SENSORY, COGNITIVE & LIMBIC
PATHWAYS.
• APPROPRIATE BEHAVIORAL RESPONSE
• ENDOCRINE ACTIVITY
• SEXUALITY & REPRODUCTION.
28. • STIMULATION OF AMYGDALA- CAUSES CHANGES IN MOOD. ALSO IT MAY
ACTIVATE VARIOUS SYMPATHETIC & PARASYMPATHETIC RESPONSES
INVOLVING PUPILLARY, CARDIOVASCULAR & VISCERAL RESPONSES AND
ALTERATION OF BREATHING.
• DESTRUCTION OF AMYGDALA- RESULTS IN PASSIVE, DEFENSIVE,
AGGRESSIVE BEHAVIOR.
• IT CAN PRODUCES EMOTIONAL INSTABILITY, RESTLESSNESS, INCREASED
INTEREST IN FOOD, HYPERSEXUALITY & KLUVER-BUCY SYNDROME.
29. KLUVER-BUCY SYNDROME
• RESULTS FROM BILATERAL DESTRUCTION OF TEMPORAL LOBES OR
AMYGDALA.
• CHARACTERISTICS:
• TAMENESS
• EXCESSIVE AND INDISCRIMINATE SEXUAL BEHAVIOR
• HYPERMETAMORPHOSIS
• HYPERORALITY
• IN HUMANS, PATHOLOGIES INCLUDE: TRAUMA, HERPES SIMPLEX
ENCEPHALITIS, AND FRONTOTEMPORAL DEMENTIA
30. SEPTAL AREA
• IT IS A GRAY MATTER STRUCTURE.
• LOCATED ABOVE ANTERIOR COMMISSURE.
• SEPTAL NUCLEI ARE RECIPROCALLY CONNECTED WITH
HIPPOCAMPUS, AMYGDALA & HYPOTHALAMUS.
• FUNCTION-
• PLEASURE RESPONSE
• SUPPRESSION OF AGGRESSION.
31. • THE SEPTAL NUCLEI RECEIVE RECIPROCAL CONNECTIONS FROM THE
OLFACTORY BULB, HIPPOCAMPUS, AMYGDALA, HYPOTHALAMUS,
MIDBRAIN, HABENULA, CINGULATE GYRUS, AND THALAMUS.
• THE SEPTAL AREA (MEDIAL OLFACTORY AREA) HAS NO RELATION TO
THE SENSE OF SMELL, BUT IT IS CONSIDERED A PLEASURE ZONE IN
ANIMALS.
32. FUNCTIONS OF SEPTAL AREA
• THE SEPTAL AREA IS A SUBCORTICAL REGION THAT HAS STRONG
PROJECTIONS TO EMOTION-GENERATING AREAS AND HAS A
KEY ROLE IN FEELINGS OF SOCIAL CONNECTEDNESS AND BONDING.
• IN EXPERIMENTAL STUDIES, THE SEPTAL NUCLEI APPEAR TO PLAY A
ROLE IN EMOTIONAL BEHAVIORS, SEXUAL BEHAVIOR, AGGRESSIVE
BEHAVIOR, MODULATION OF AUTONOMIC FUNCTIONS, AND
ATTENTION AND MEMORY FUNCTIONS (FROM THE CHOLINERGIC
NEURONS).
33. CONNECTIONS OF SEPTAL AREA
• AFFERENTS:
• HIPPOCAMPUS
• CORTICOMEDIAL AND
BASOLATERAL AMYGDALA
• VENTRAL TEGMENTAL NUCLEUS IN
THE MIDBRAIN
• SEVERAL HYPOTHALAMIC NUCLEI.
• EFFERENTS:
• HIPPOCAMPUS AND DENTATE
GYRUS (VIA THE FORNIX)
• HABENULAR NUCLEI (VIA THE STRIA
MEDULLARIS THALAMI)
• MEDIAL DORSAL NUCLEUS OF
THE THALAMUS (VIA THE STRIA
MEDULLARIS THALAMI)
• VENTRAL TEGMENTAL AREA (VIA
THE MEDIAN FOREBRAIN BUNDLE)
• SEVERAL HYPOTHALAMIC NUCLEI.
34. REWARD BEHAVIOR & PLEASURABLE
SENSATION
• ALSO SEEM TO HAVE LIMBIC BASIS.
• ANIMALS WITH ELECTRODES IMPLANTED IN A SEPTAL REGION.
(ELECTRICAL SELF-STIMULATION AND REWARD)
• IN THIS EXPERIMENT, REACTIONS SUGGEST SEPTAL AREA AS A PLEASURE
CENTRE.
• PAUL YAKOVLEV SUGGESTED, POSTERIOR CINGULATE GYRUS CONTAINED
A FEELING GOOD CENTRE, WHICH MIGHT CONTROL MOODS OF ELATION,
BUT AMYGDALA & OTHER LIMBIC CONNECTIONS ALSO PARTICIPATE IN IT.
35.
36. HYPOTHALAMUS
• THE HYPOTHALAMUS IS LOCATED IN THE VENTRAL AREA OF THE
BRAIN BETWEEN THE PITUITARY GLAND AND THE THIRD VENTRICLE.
• IT IS CHARACTERIZED AS A BILATERAL GROUP OF NUCLEI WHICH
SURROUND MAMMILLARY BODIES.
• EACH GROUP OF NUCLEI IS COMPRISED OF DISTINCTIVE NEURONAL
POPULATIONS WHICH FORMULATE SEVERAL NEUROTRANSMITTERS
AND NEUROPEPTIDES WHICH WORK TO REGULATE THE BODILY
FUNCTIONS REFERRED TO AS HOMEOSTASIS.
37. CONNECTIONS
• AFFERENT:
• THALAMUS
• CEREBRAL CORTEX
• BRAINSTEM
• OLFACTORY AREAS
• BASAL GANGLIA
• ONE OF THE MOST SIGNIFICANT
EFFERENT PATHWAYS CONSISTS
OF THE NETWORK THAT LINKS
THE SUPRAOPTIC AND
PARAVENTRICULAR NUCLEI OF
THE HYPOTHALAMUS TO THE
MEDIAN EMINENCE, WHICH
VERGE TO THE POSTERIOR AND
ANTERIOR PITUITARY GLANDS.
38.
39. FUNCTIONS OF HYPOTHALAMUS
FUNCTIONS:
• REGULATES HOMEOSTASIS
• HUNGER
• THIRST
• BODY TEMP, BLOOD PRESSURE
• SEX DRIVES & BEHAVIOR
• EMOTIONS VIA LIMBIC SYSTEM
• PITUITARY GLAND
• CIRCADIAN RHYTHMS
40. • LATERAL PORTION OF HYPOTHALAMUS CONTAINS LOW DENSITY OF
NEURONS, WHICH INTERCONNECTED WITH FOREBRAIN, BRAIN STEM
& SPINAL CORD.
• LATERAL HYPOTHALAMUS ALSO CONTAINS NEURONS EXPRESS
OREXIN NEUROPEPTIDES- OREXIN A & B. OREXIN NEURONS ARE
INVOLVED IN SLEEP & WAKEFULNESS.
• OREXIN DEFICIENCY IS A MAIN CAUSE OF NARCOLEPSY.
41. MAMILLARY BODIES
• LOCATION: AT THE END OF FORNIX.
• ACT AS A RELAY FOR IMPULSES COMING FROM THE HIPPOCAMPUS.
• AND VIA THE MAMILLO-THALAMIC TRACT TO THE THALAMUS.
• THIS CIRCUIT, FROM HIPPOCAMPUS TO MAMMILLARY BODIES, AND
THEN ON TO THE THALAMUS, IS PART OF THE 'PAPEZ CIRCUIT'.
42.
43. • MAMMILLOTEGMENTAL TRACT: IS A SMALL BUNDLE OF EFFERENT
FIBERS FROM THE HYPOTHALAMUS RUNNING FROM
THE MAMMILLARY BODY TO THE TEGMENTUM. ITS FUNCTIONS ARE
NOT WELL DEFINED FOR HUMANS, BUT BASED ON ANIMAL STUDIES
IT SEEMS TO BE RELATED TO REGULATING VISCERAL FUNCTION AND
PROCESSING SPATIAL INFORMATION.
• THEY, ALONG WITH THE ANTERIOR AND DORSOMEDIAL NUCLEI IN
THE THALAMUS, ARE INVOLVED WITH THE PROCESSING OF MEMORY.
44. LESION TO THE MAMMILLARY BODIES
• DAMAGE TO THE MAMMILLARY BODIES DUE
TO THIAMINE DEFICIENCY IS IMPLIED IN PATHOGENESIS
OF WERNICKE-KORSAKOFF SYNDROME.
• SYMPTOMS INCLUDE IMPAIRED MEMORY, ALSO
CALLED ANTEROGRADE AMNESIA, SUGGESTING THAT THE
MAMMILLARY BODIES MAY BE IMPORTANT FOR MEMORY.
• LESIONS OF THE MEDIAL DORSAL AND ANTERIOR NUCLEI OF THE
THALAMI AND LESIONS OF THE MAMMILLARY BODIES ARE
COMMONLY INVOLVED IN AMNESIC SYNDROMES IN HUMANS.
45. • MAMMILLARY BODY ATROPHY IS PRESENT IN A NUMBER OF OTHER
CONDITIONS, SUCH AS COLLOID CYSTS IN THE THIRD VENTRICLE,
ALZHEIMER’S DISEASE, SCHIZOPHRENIA, HEART FAILURE, AND SLEEP
APNEA.
46. ANTERIOR NUCLEUS OF THALAMUS
• COLLECTION OF NUCLEI AT THE ROSTRAL END OF THE DORSAL
THALAMUS. THEY COMPRISE THE ANTEROMEDIAL, ANTERODORSAL,
AND ANTEROVENTRAL NUCLEI.
48. DAMAGE TO ANTERIOR NUCLEUS
• DAMAGE TO THE ANTERIOR NUCLEUS OF THALAMUS LEADS TO
IMPAIRMENT IN EPISODIC MEMORY.
49. NEUROPSYCHIATRIC ASPECT OF LIMBIC
SYSTEM
• THE LIMBIC SYSTEM HAS BEEN PARTICULARLY IMPLICATED IN
NEUROPATHOLOGICAL STUDIES OF SCHIZOPHRENIA. EUGEN
BLEULER’S WELL-KNOWN FOUR A’S OF SCHIZOPHRENIA—AFFECT,
ASSOCIATIONS, AMBIVALENCE, AND AUTISM—REFER TO BRAIN
FUNCTIONS SERVED IN PART BY LIMBIC STRUCTURES.
• IN PATHOLOGICAL AS WELL AS IN MAGNETIC RESONANCE IMAGING
(MRI) REPORTS, PERSONS WITH SCHIZOPHRENIA MAY HAVE REDUCED
VOLUME OF THE HIPPOCAMPUS, AMYGDALA, AND
PARAHIPPOCAMPAL GYRUS.
50. • ANXIETY DISORDERS: IN PET SCANS FOR PANIC ATTACK PATIENT,
AMYGDALA APPEARS HIGHLY ACTIVATED TRIGGERING A
SYMPATHETICALLY MEDIATED ‘FIGHT OR FLIGHT’ RESPONSE.
51. • LIMBIC EPILEPSY -VOLUMINOUS MENTAL STATE : DÉJÀ VU,
DEPERSONALIZATION/DEREALIZATION, MICROPSIA AND
MACROPSIA.
• PAROXYSMAL LIMBIC PHENOMENA: MICROPSIA, MACROPSIA,
METAMORPHOPSIA, DÉJÀ VU, AND JAMAIS VU, DÉJÀ ÉCOUTÉ, AND
JAMAIS ÉCOUTÉ.
52. • PERSISTING SUBSTANTIAL AMNESTIC DEFICITS IN MULTIPLE
MODALITIES.
• GLIOMAS OF LIMBIC SYSTEM & CORPUS CALLOSUM :CHANGES IN
MOOD, AFFECT, DRIVE & GENERAL BEHAVIOR.
• LIMBIC ENCEPHALITIS: AUTOANTIBODIES LIKE ANTI-HU, ANTI-MA2,
ANTI-NMDA RECEPTOR
The EC is the main interface between the hippocampus and neocortex. The EC-hippocampus system plays an important role in declarative (autobiographical/episodic/semantic) memories and in particular spatial memories including memory formation, memory consolidation, and memory optimization in sleep.
These regions form the trilaminar loop, which is the processing center of long-term memory. Long-term potentiation (LTP), which is a form of neural plasticity, occurs in the hippocampus, and LPT is a vital brain mechanism involved in memory storage.
Korsakoff syndrome is a chronic memory disordercaused by severe deficiency of thiamine (vitamin B-1).Korsakoff syndrome is most commonly caused by alcohol misuse, but certain other conditions also can cause the syndrome.
Hypermetamorphosis: A tendency to attend indiscriminately and react to every visual stimulus
A circadian rhythm is a natural, internal process that regulates the sleep-wake cycle and repeats roughly every 24 hours.
Narcolepsy is a sleep disorder characterized by excessive sleepiness, sleep paralysis, hallucinations, and in some cases episodes of cataplexy (partial or total loss of muscle control, often triggered by a strong emotion such as laughter).
Déjà vu:a feeling of having already experienced the present situation.
Depersonalisation: a state in which one's thoughts and feelings seem unreal or not to belong to oneself.
Metamorphopsia is a visual defect that causes linear objects, such as lines on a grid, to look curvy or rounded.
Jamais vu: phenomenon of experiencing a situation that one recognizes in some fashion, but nonetheless seems very unfamiliar.
Deja ecoute: is the feeling of having already dreamed something that you are now experiencing.
jamais écouté: sensation of unfamiliarity with a sound that should be recognized.