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CENTRAL INTEGRATIVE SYSTEMS. D. C. MIKULECKY PROFESSOR OF PHYSIOLOGY AND FACULTY MENTORING PROGRAM. BODY RHYTHMS AND THE HYPOTHALAMUS. CIRCADIAN RHYTHMS AND BIOLOGICAL CLOCKS SLEEP. CIRCADIAN RHYTHMS AND BIOLOGICAL CLOCKS. OVER 100 BODY FUNCTIONS VARY ON A 24-HOUR SCHEDULE
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CENTRAL INTEGRATIVE SYSTEMS D. C. MIKULECKY PROFESSOR OF PHYSIOLOGY AND FACULTY MENTORING PROGRAM
BODY RHYTHMS AND THE HYPOTHALAMUS • CIRCADIAN RHYTHMS AND BIOLOGICAL CLOCKS • SLEEP
CIRCADIAN RHYTHMS AND BIOLOGICAL CLOCKS • OVER 100 BODY FUNCTIONS VARY ON A 24-HOUR SCHEDULE • THYROXIN SECRETION CONTROLLED BY THE HYPOTHALAMUS • ALSO ACTH AND CORTISONE • MASTER CLOCK: SUPRACHIASMATIC NUCLEUS OF THE HYPOTHALAMUS
MANIFESTATIONS OF DAILY RHYTHMS • BODY TEMPERATURE VARIATION • DISRUPTION CAUSES PROBLEMS: JET LAG
SLEEP • SLEEP HAS DIFFERENT STAGES • NEURAL MECHANISMS OF SLEEP • SLEEP DISORDERS
SLEEP HAS DIFFERENT STAGES • 3 TO 5 CYCLES PER NIGHT CONSISTING OF 5 STAGES (I - V AND REM) • SLEEP STAGES BASED ON EEG ACTIVITY • RAPID EYE MOVEMENT (REM) SLEEP • SLEEP PATTERNS VARY WITH AGE
3 TO 5 CYCLES PER NIGHT CONSISTING OF 5 STAGES (I - V AND REM) • FREQUENCY OF ELECTRICAL ACTIVITY DECREASES AS AMPLITUDE INCREASES • BY STAGE 4 HEART RATE AND BLOOD PRESSURE HAVE DECREASED WHILE GI MOTILITY INCREASES (PARASYMPATHETIC ACTIVITY) • REM SLEEP TAKES THE BRAIN FROM STAGE 4 BACK TO STAGE 1 (SYMPATHETIC ACTIVITY) • REM SLEEP IS ASSOCIATED WITH VISUAL DREAMING
SLEEP PATTERNS VARY WITH AGE • WITH AGE TOTAL SLEEP TIME DECREASES • ALSO THE % REM SLEEP • ALSO THE TIME SPENT IN STAGE 4
NEURAL MECHANISMS OF SLEEP • THE HYPOTHALAMUS AND BRAIN STEM ARE RESPONSIBLE FOR SLEEP/AWAKE CYCLES • THE PREOPTIC AREA OF THE HYPOTHALAMUS INDUCES NON-REM SLEEP • SEROTONON WILL ALSO INDUCE SLEEP WHEN INJECTED INTO THIS AREA • RAPHE NUCLEUS MAY BE THE GENERATOR OF REM SLEEP
SLEEP DISORDERS • INSOMNIA: INABILITY TO SLEEP, MAY BE CAUSED BY DISRUPTION OF CIRCADIAN RHYTHMS. • NARCOLEPSY: ATTACKS OF SLEEP AT ANY TIME, MAY BE DUE TO RAPHE NUCLEUS REM-SLEEP GENERATOR. AN INHERITED DISORDER. TREATED WITH AMPHETAMINES
MOTIVATIONAL SYSTEMS • HUNGER • THIRST • SEXUAL BEHAVIOR
HUNGER GLUCOSE RECEPTORS IN HYPOTHALAMUS REDUCED AVAILABILITY OF GLUCOSE SHORT TERM MECHANO- RECEPTORS IN STOMACH CONTRACTIONS OF EMPTY STOMACH HUNGER LACK OF FOOD LOW TRIGLYCERIDE LEVELS IN FAT CELLS LONG TERM PANCREAS
THIRST OSMORECEPTORS IN SUPRAOPTIC AND SUPRA- VENTRICULAR NUCLEI OF HYPOTHALAMUS THIRST WATER DEFICIENCY WATER RETENTION BY KIDNEY ADH SERETION BY PITUITARY
SEXUAL BEHAVIOR • ANTERIOR HYPOTHALAMUS ORGANIZES RESPONSES TO PHERMONES • OLIFACTORY CUES SENT TO PYRIFORM CORTEX AND AMYGDALA AND INDIRECTLY TO HYPOTHALAMUS • ANDROGENS DETERMINE RELEASE OF LEUTINIZING HORMONE- CONSTANT OR CYCLIC
LEARNING AND MEMORY • ASSOSCIATIVE VS NONASSOCIATIVE LEARNING • SHORT AND LONG TERM MEMORY • NEURONAL PATHWAYS • SPLIT BRAIN STUDIES • CELLULAR MANIFESTATIONS • USE AND DISUSE
ASSOSCIATIVE VS NONASSOCIATIVE LEARNING • HABITUATION AND SENSITIZATION ARE NONASSOCIATIVE • CLASSICAL CONDITIONING IS ASSOCIATIVE • OPERANT CONDITIONING IS ASSOCIATIVE
CONDITIONED REFLEX RESPONSE: CLOSE EYE RED NUCLEUS STIMULUS: AIR PUFF ON EYE CEREBELLUM PURKINJE CELL OLIVARY NUCLEUS CLIMBING FIBER
CONDITIONED REFLEX CONDITIONING STIMULUS: TONE RESPONSE: CLOSE EYE RED NUCLEUS COCHLEAR NUCLEUS STIMULUS: AIR PUFF ON EYE CEREBELLUM PURKINJE CELL OLIVARY NUCLEUS PONTINE NUCLEUS MOSSY FIBERS CLIMBING FIBER
CONDITIONED REFLEX CONDITIONING STIMULUS: TONE RESPONSE: CLOSE EYE RED NUCLEUS COCHLEAR NUCLEUS CEREBELLUM PURKINJE CELL PONTINE NUCLEUS MOSSY FIBERS
SHORT AND LONG TERM MEMORY • SHORT-TERM MEMORY INVOLVES IMMEDIATE USE, IS EASILY DISRUPTED AND AND IS SHORT LIVED • LONG-TERM MEMORY IS MORE STABLE • INFORMATION IS PASSED FROM SHORT- TERM TO LONG-TERM MEMORY BY A PROCESS CALLED CONSOLIDATION
NEURONAL PATHWAYS • MEMORY CIRCUITS PROVIDE A SIMPLE EXPLANAION FOR MEMORY • THESE INVOLVE THE HYPOTHALAMUS AND AMYGDALA AS WELL AS THE TEMPORAL LOBE AND THE HIPPOCAMPUS
SPLIT BRAIN STUDIES • INFORMATION IS PROCESSED AND STORED DIFFERENTLY IN DIFFERENT SPECIES • MONKEYS NEED BOTH HEMESPHERES WHILE CATS CAN LEARN IN ONE HEMISPHERE AND TRANSFER THE INFORMATION TO THE OTHER
CELLULAR MANIFESTATIONS • HABITUATION IS A DECREASE IN SYNAPTIC TRAQNSMISSION IN RESPONSE TO A REPEATED STIMULUS • SENSITIZATION INVOLVES AN INCREASE IN TRANSMITTER RELEASE • CLASSICAL CONDITIONING IS A SENSITIZATION PROCESS
USE AND DISUSE • IN EXERCISE MUSCLES INCREASE MASS WITH USE • NEURAL PATHWAYS CAN STRENGTHEN OR WEAKEN CONNECTIONS BETWEEN NERVE CELLS • THE OPPOSITE ALSO HAPPENS: ATROPHY WITH DISUSE
LANGUAGE SYSTEMS • DOMINANT AND NONDOMINANT HEMISPHERES • ANATOMICAL CORRELATES OF SPEECH DISORDERS
LOCALIZATION OF LANGUAGE FUNCTIONS ASSOCIATION COMPREHENSION MOTOR PROGRAMS
DOMINANT AND NONDOMINANT HEMISPHERES • TYPICALLY, SPEECH AREA IN DOMINANT HEMISPHERE IS LARGER • THIS DIFFERENCE APPEARS IN THE HUMAN FETUS BY THE 31ST WEEK OF GESTATION • NONDOMINANT HEMISPHERE IS RESPONSIBLE FOR INTONATION AND EMOTIONAL ASPECTS
ANATOMICAL CORRELATES OF SPEECH DISORDERS • NONDOMINANT CORRELATE OF WERNICKE’S AND BROCA’S AREAS: APROSODIAS-INABILITY TO UNDERSTAND OR EXPRESS INTONATION • APHASIAS: LANGUAGE DISORDER DUE TO BRAIN DAMAGE • DYSLEXIA: CONGENITAL DISORDER AFFECTING READING
APHASIAS • BROCA’S: DISRUPTION OF MOTOR CENTERS-AFFECTS BOTH SPEECH AND WRITING • WERNICKE’S AREA: LOSS OF COMPREHENSION
LATERALITY OF BRAIN FUNCTION • RIGHT AND LEFT BRAIN • GENDER DIFFERENCES
RIGHT AND LEFT BRAIN • RIGHT HEMISPHERE: SPATIAL ABILITIES, ARTISTIC AND MUSICAL ABILITY • LEFT HEMISPHERE: ANALYTICAL SKILLS
GENDER DIFFERENCES • MALES TEND TO EXHIBIT MORE LATERALIZATION OF SPECIFIC TASKS • FEMALES USE BOTH HEMISPHERES MORE SYMMETRICALLY