Sleep Disorders. Sleep. Circadian Rhythms

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Sleep Disorders Sleep The Sleep Wakefulness Cycle: Circadian Rhythms Internally generated patterns of bodily functions that vary over a ~24-hour period Function even in the absence of normal

1 Sleep Disorders Sleep The Sleep Wakefulness Cycle: Circadian Rhythms Internally generated patterns of bodily functions that vary over a ~24-hour period Function even in the absence of normal cues 2 Circadian Rhythms Disruptions to the circadian rhythm Can lead to thinking less clearly, inattentiveness, and feeling sleepy Due to shifting work schedules, jet lag, pulling an all nighter 3 1

2 Circadian Rhythms Accommodating disruptions to the circadian rhythm Change schedule slowly Follow normal schedule, rather than trying to adjust to the new time zone Get exposure to bright light to increase wakefulness Small doses of melatonin promote sleep 4 Sleep Stages REM and NREM Sleep 1. Studying Sleep Electroencephalograms (EEGs) Graphically record brain-wave activity through electrodes placed on the scalp and forehead EEG waves vary in frequency and amplitude 5 EEGs These differ in frequency: These differ in amplitude: 6 2

3 Two Types of Sleep 1. Rapid Eye Movement (REM) Sleep High-frequency, low amplitude brainwave activity Systematic eye movements also occur during REM REM sleep occurs only after four stages of non-rem (NREM) sleep 7 Two Types of Sleep 2. NREM Sleep Increasing bodily relaxation Slower EEG activity Slower heart rate and respiration More difficult to awaken as the four stages of NREM sleep progress 8 Sleep Stages Stages 1-4 Non-Rapid Eye Movement NREM) Light sleep. Low amp, mixed frequency. Easily awakened. Low amp. Relaxed deeper sleep. Slower & high amp, low frequency. Delta waves. Most difficult to awaken. cycles minutes. ( 1, 2, 3, 4, 3, 2, 9 1). 3

4 REM Sleep Very different from NREM sleep Difficult to distinguish from being awake on the basis of physiological measures People in REM are more difficult to awaken Sleepwalking can not occur during REM sleep 10 REM Sleep Sleepers are more likely to report dreams when awakened from REM Dreams do occur in other stages Dreams are more vivid, long-lasting, and detailed in REM sleep REM Sleep sometimes called paradoxical sleep Asleep but aroused Small movements, but paralyzed 11 Sleep Deprivation The longer a person is deprived of sleep, the greater the effect will be 12 4

5 Sleep Deprivation Chronic neglect of sleep is a common and dangerous problem Can not study total sleep deprivation in humans for ethical reasons However, rats totally deprived of sleep die 13 Why Do We Sleep? Because we are tired Sleep has a restorative function What is restored by sleep has not been identified Fatigue does not relate directly to sleep Bedridden people sleep as much as people on their feet all day Heavy exercise has little effect on need for sleep 14 Repair & Restoration Theory Makes repairs, restores digestion, removes waste, restore Norepi & dopamine Neural Basis: hypothalamus, forebrain, limbic system, brain stem. Exercises neurons. 15 5

6 Evolution/Adaptation Theory Sleep requires less energy and keeps us out of danger However, also seems to represent a nonadaptive vulnerability Hibernation: Decreases heart rate, brain activity, conserve energy, metabolism, body temp 16 Consolidation of Memory Rehearse or preserve information learned though out the day 17 Why Do We Sleep? Obviously, no single theory fully explains why we sleep Sleep likely serves many functions Several theories may be needed to explain it Is there a sleep switch? What makes people go to sleep and wake up? Brain systems in the hypothalamus seem to turn on sleeping and waking 18 6

7 Sleep Disorders Dysomnias: Predominantly disturbances in the amount, quality, or timing of sleep. NOT DUE TO DRUGS/ALCOHOL, EDICATION OR GENERAL MEDICAL CONDITION DSM IV: Primary sleep disorders 19 Narcolepsy Sudden, uncontrollable episodes of sleep People with narcolepsy experience muscle weakness and fall uncontrollably asleep Affects about 1 in 2,000 people Has a genetic component Effective drug treatment has been developed 20 Sleep Apnea The sleeper stops breathing, chokes, then wakens briefly Causes airflow to stop for at least 15 seconds Loud snoring is a symptom Can be life threatening Associated with excessive daytime sleepiness, and possibly memory loss, severe headaches, work-related injuries, SIDS Middle-aged, overweight men are at increased risk, but sleep apnea can even affect children Several effective therapies that keep the airway clear have been developed 21 7

8 Insomnia Difficulty in getting or staying asleep Affects as many as 1 in 10 people Insomniacs feel listless and tired during the day Etiology: stress, anxiety, bad sleep habits, psychopathology, age More common in females Behavioral treatments for insomnia include relaxation training, thought restructuring, and self-hypnosis 22 Hypersomnia Excessive daytime sleepiness (for at least one month). - Falls asleep easily w/i 5 min. anytime - Common with obesity - Usually treated with stimulants, antidepressants. 23 Circadian Rhythm Sleep Disorder Mismatch between a person s sleep wake pattern that is normal with his/her environment 24 8

9 Parasomnias Predominant disturbance is an abnormal behavioral or physiological event occurring during sleep 25 Nightmare Disorder Formerly known as Dream Anxiety Disorder Bad dreams Repeated awakenings from sleep with detailed recall of frightening dreams. Occurs during periods of REM 26 Sleep Terror Disorder Repeated episodes of abrupt awakenings from sleep, usually with a panicky scream. Person is difficult to calm. No recollection the next morning. Panic attacks that occur within minutes of falling asleep They occur in NREM sleep, usually stage

Sleep Terror Disorder They are not nightmares Sleep terrors are common in children between ages 3 and 8 Cause is not well understood 28 Sleep Walking Disorder Repeated episodes of the person leaving

10 Sleep Terror Disorder They are not nightmares Sleep terrors are common in children between ages 3 and 8 Cause is not well understood 28 Sleep Walking Disorder Repeated episodes of the person leaving bed & walking about w/o being conscious of the episode or later remembering it 29 Sleep Walking Disorder Runs in families More common in male children It tends to decrease with age Sleepwalkers are in stage 4 sleep In stage 4, motor portions of the brain are active Cognitive portions of the brain show little activity in this stage Person may be confused or startled upon awakening 30 10

11 Dreams and Dreaming What is a Dream? A state of consciousness that occurs during sleep Usually accompanied by vivid imagery Associated with REM sleep Dreams do occur during NREM sleep, but tend to be less bizarre and contain less action imagery Most people have dreams every night, but forget them when they do not awaken during or soon after a dream More dreaming occurs during the second part of the night If we dream in 80% of REM periods, we dream three 31 or four times a night Content of Dreams Dreams are mostly visual, and most are in color Most dreams focus on events and people a person comes into contact with Lucid dreaming occurs when one is aware of dreaming as it happens 32 Dream Theories Psychodynamic Views (Freud) Dreams are the royal road to the unconscious Freud believed dreams expressed desires, wishes, and unfulfilled needs that exist in the unconscious 33 11

12 Freud Two types of content Manifest content Consists of its overt story line, characters, and setting Latent content The deeper meaning, usually involving symbolic ideas and wishes These wishes might make the person uncomfortable if expressed overtly 34 Psychodynamic Views Carl Jung ( ) Three purposes of dreams: An attempt to make sense of life s tasks To compensate for unconscious urges To predict the future Jung asserted dreams give expression to the collective unconscious 35 Carl Jung Collective Unconscious Storehouse of primitive ideas and images inherited from our ancestors that is shared by all people These inherited ideas and images are archetypes Representations of archetypes emerge as dreams 36 12

13 Modern Approaches Evidence from neuroscience seen as consistent with Freud s view that dreams are expressions of the unconscious Other see similarities with Native American philosophies Dreams as a route to empowerment and enlightenment Not seen as a separate state of consciousness, but as an altered reality 37 Cognitive View Dreams reflect the same kind of thinking people do when they are awake Dreams express current wishes, desires, and issues the person is dealing with Bilingual people dream about things related to the language they used before sleeping 38 13

Psychology of Consciousness

Psychology of Consciousness Chapter 4 Consciousness I. What is Consciousness? II. What Happens When We Sleep? III. What Are Dreams and What Do They Mean? IV. Is it Possible to Control Consciousness by