BIOPSYCH 0505 Edition 1nd Exam 2 Study Guide Lectures 8 17 Lecture 8 February 6th Sleep early evolutionary behavior and has an adaptive evolutionary function Recuperation theories of sleep Restorative theory Repairs and regenerations the body Deprived sleep entails lower body temperature and shiver more increased blood pressure a weakened immune system and the metabolism tends to slow down Restoration of the brain it s likely that sleep is more important for brain mainly the frontal lobe restoration than body restoration Necessary for optimal functioning of physiological systems muscle hormone and tissue growth occurs during sleep Elimination theory We sleep to get rid of excess sensory information The hippocampus activity level increases during sleep certain synaptic connections are strengthened and others are weakened Adaptation theories of sleep Circadian day and night cycle is related to the light dark cycle Immobilization theory Sleep is an innate response with species specific patterns humans cant see well in the dark so it makes sense to sleep during the night Keeps one inactive and safe in the least efficient part of the light cycle Energy conservation theory Following survival activities periods of inactivity are a good way to conserve energy What are the functions of slow wave sleep It is more essential for survival and is a deeper level restorative sleep It reduces free radicals which are atoms who have lost an electron and have to steal an electron from another cells produces cellular damage as the level of free radicals is correlated to diseaseless free radicals is better for the body What are the functions of REM sleep It promotes brain development The REM rebound phenomenon occurs in everyone when they are REM sleep deprived as you can make up for the lost REM sleep as a catch up making up the quality of sleep not the quantity of hours Measurement of sleep and arousal Electroencephalogram EEG electrical potential recorded from electrodes places on the scalp to monitor brain wave activity Eletrooculogram EOG measure of eye movements during sleep SWS rolling eye movements REM rapid eye movement Electromyogram EMG measures changes in muscle tension and activity practically in the facial and neck muscles the mentalist muscle is located between the lip and chin that will be tense while awake and totally relaxed when asleep Lecture 9 February 11th Theories of Sleep Passive theory of sleep Sleep is a passive process that if you weren t stimulated you would fall asleep Sleep was the result of inactivity Cerveau isole the isolated forebrain a cut through the midbrain so that the forebrain was completely separated from the rest of the brain and found that the cat slept all the time yet the auditory and visual systems were still in tact Encephale isole isolated brain the entire encephalon is separated from the spinal cord which is cut at the medulla yet the normal sleep wake patterns led Bremer to think that maybe sleep was not passive Active theory of sleep Found nuclei pathways when you separated the entire brain which allows for the regulation of sleep and wake The pathway of arousal was cut in the cerveau isole some neurons induce wakefulness and sleepiness Reticular activating system sending pathway of the reticular formation majority of it in the pons Sleep cycle lasts about 90 minutes Alert wakefulness Beta waves alert wakefulness of a high frequency Range for amplitude is up to 30 microvolts Frequency of hertz 13 30 Just before sleep Alpha waves occur just before falling asleep Considered to have a low amplitude 10 20 microvolts Frequency of 8 12 hertz Stage 1 sleep Theta waves that are of a mixed frequency which is irregular Have a medium amplitude up to 50 microvolts Frequency of 4 to 7 hertz across Transitional stage of sleep that lasts between 1 to 7 minutes or 5 of your sleep Stage 2 sleep Theta waves Still easy to wake out of this sleep Sleep spindles high frequency burst of wave that lasts about one second and can have 2 5 per minute correlated with muscle twitching K complexes large wave that have high amplitude and a low frequency and only found in stage 2 children have more sleep spindles and k complexes than adults Stage 3 sleep Delta waves are beginning to be seen which are large amplitude of 100 microvolts with a low frequency of 1 2 hertz Theta carriers are still there 10 of your sleep which is a transition to stage 4 Stage 4 sleep Mostly delta waves with very low frequency 20 50 of your sleep occurs in the first few hours Night terrors occur REM sleep stage 5 Dream stage of sleep as the dreams are more fluid and real like Occurs where stage 1 sleep typically occurs A lot of cortical arousal and is paradoxical where the wave patterns indicate that you are awake and asleep at the same time Have a mix of a few delta and mostly theta and alpha waves Lecture 10 February 13th Neurotransmitters Arousal waking state Acetylcholine Dorsal pons and basal forebrain right in front of hypothalamus Plays a role in arousal of the cerebral cortex The activity levels are high during REM sleep and higher during waking Involved in cortex and hippocampus arousal Norepinephrine Locus coeruleus in pons Plays a role in attention and vigilance and a possible role in behavioral arousal Activity levels are high only during waking and lover levels during SWS lowest levels during REM Impacts the cortex thalamus hippocampus cerebellum pons and medulla Serotonin Nuclei medial pons near the caudal end of the reticular formation Activity levels high during waking and low as descending into REM sleep Cortical and behavioral arousal plays a role in activating behavior chewing pacing Impacts the thalamus hypothalamus cortex hippocampus and the basal ganglia part of the motor system Histamine Tuberomammillary nucleus in the hypothalamus Activity levels high during waking and low during SWS and REM Implicated in the control of wakefulness and arousal Impacts the cortex thalamus hypothalamus basal ganglia and basal forebrain Orexin From the lateral hypothalamus Increase activity in the brain stem and forebrain arousal systems and connected to narcolepsy Stimulated by hunger satiety signals and the biological clock Slow wave sleep GABA from ventrolateral preoptic vlPOA area and uppresses alertness and behavioral arousal which promotes sleep Adenosine peptide is released by neurons during high levels of metabolic activity through out the day and is very low when you first wake up increases