Sleep & Dreams Chapter 5 Section 2

Main Idea:  Sleeping and dreaming are essential to human health, although many questions remain. Some people are troubled by various sleep problems.

The Sleep Cycle  Circadian rhythms (biological clock)- include a sequence of bodily changes, body temperatures, blood pressure, & sleepiness and wakefulness that occurs every 24 hours

Stages of Sleep  Stages are defined in terms of brain-wave patterns, which are measured by an electroencephalograph (EEG)  Brain waves are cyclical, they vary on the basis of whether we are awake, relaxed, or sleeping  Four different brain waves- beta, alpha, theta, and delta  Stages are defined in terms of brain-wave patterns, which are measured by an electroencephalograph (EEG)  Brain waves are cyclical, they vary on the basis of whether we are awake, relaxed, or sleeping  Four different brain waves- beta, alpha, theta, and delta

 Awake and alert- beta waves (short and quick)  Drowsy- alpha waves (little slower than beta)  Drowsy phase is followed by the 5 stages of sleep  Awake and alert- beta waves (short and quick)  Drowsy- alpha waves (little slower than beta)  Drowsy phase is followed by the 5 stages of sleep

 Stage 1- stage of the lightest sleep- slower pattern of theta accompanied by brief images that resemble vivid photos  So light that we may not have felt like we slept at all  (stage 1 lasts about minutes)  Stage 1- stage of the lightest sleep- slower pattern of theta accompanied by brief images that resemble vivid photos  So light that we may not have felt like we slept at all  (stage 1 lasts about minutes)

 After stage 1 we move into stages 2,3,4  Stage 2- deeper sleep than 1  Stage 3 & 4- experience delta waves and deeper sleep  Stage 4- deepest level of sleep, hardest to wake a person in stage 4  After stage 1 we move into stages 2,3,4  Stage 2- deeper sleep than 1  Stage 3 & 4- experience delta waves and deeper sleep  Stage 4- deepest level of sleep, hardest to wake a person in stage 4

 After about 30 mins of sleep in stage 4 we revert back to stage 1  After about 90 mins changes occur- suddenly we breathe more irregularly, blood pressure rises, and heart beats faster, brain waves become similar to that of stage 1  After about 30 mins of sleep in stage 4 we revert back to stage 1  After about 90 mins changes occur- suddenly we breathe more irregularly, blood pressure rises, and heart beats faster, brain waves become similar to that of stage 1

 Final stage- rapid-eye-movement (REM)  Beneath our eyelids our eyes are moving rapidly  Preceding 4 stages referred to as non-rapid-eye- movement (NREM)  Typical 8 hour night of sleep most go through these stages about 5 times- each 1 sleep cycle  Final stage- rapid-eye-movement (REM)  Beneath our eyelids our eyes are moving rapidly  Preceding 4 stages referred to as non-rapid-eye- movement (NREM)  Typical 8 hour night of sleep most go through these stages about 5 times- each 1 sleep cycle

The Importance of Sleep & Dreams  People need sleep to help revive the tired body and to build up resistance to infection  Helps recover from stress and help consolidate certain memories from previous day  Randy Gardner-age 17  11 days no sleep; irritable, could not focus his eyes, speech difficulties, memory lapse  People need sleep to help revive the tired body and to build up resistance to infection  Helps recover from stress and help consolidate certain memories from previous day  Randy Gardner-age 17  11 days no sleep; irritable, could not focus his eyes, speech difficulties, memory lapse

Dreams  REM- most vivid dreams; dreams are most likely to have clear imagery and plots that make sense, even if some of the events aren’t realistic  During NREM- plots are vaguer and images more fleeting  Some dreams involve fantastic adventures, most are extensions of the activities of the day  REM- most vivid dreams; dreams are most likely to have clear imagery and plots that make sense, even if some of the events aren’t realistic  During NREM- plots are vaguer and images more fleeting  Some dreams involve fantastic adventures, most are extensions of the activities of the day

The Freudian View  “A dream is a wish the heart makes.”

Bio-psychological Approach  Begins with biological activity  According to this view, during sleep neurons fire in a part of the brain that controls movement and vision. These neuron bursts are random and the brain tries to makes sense of them; does so by weaving a story- dream  After a difficult day- troubling dreams  After an easy day- pleasant happy dreams  Begins with biological activity  According to this view, during sleep neurons fire in a part of the brain that controls movement and vision. These neuron bursts are random and the brain tries to makes sense of them; does so by weaving a story- dream  After a difficult day- troubling dreams  After an easy day- pleasant happy dreams

Sleep Problems  Insomnia- inability to sleep  Most common is difficulty falling asleep  Nightmares and night terrors  Night terrors more severe than nightmares; heart races, gasping for air, sudden movements, talking incoherently  Most common in young children  Night terrors occur in stages 3-4  Nightmares occur during REM sleep  Insomnia- inability to sleep  Most common is difficulty falling asleep  Nightmares and night terrors  Night terrors more severe than nightmares; heart races, gasping for air, sudden movements, talking incoherently  Most common in young children  Night terrors occur in stages 3-4  Nightmares occur during REM sleep

 sleepwalking  Many children walk in their sleep  Sleep apnea- breathing interruptions that occur during sleep  Do not automatically start breathing again until they suddenly sit up and gasp for air, once they begin breathing again they fall back to sleep  sleepwalking  Many children walk in their sleep  Sleep apnea- breathing interruptions that occur during sleep  Do not automatically start breathing again until they suddenly sit up and gasp for air, once they begin breathing again they fall back to sleep

 Narcolepsy- rare sleep problem in which people suddenly fall asleep, no matter time or place