Waking and Sleeping Rhythms

Waking Consciousness Consciousness our awareness of ourselves and our environments

Sleep and Dreams Biological Rhythms Circadian Rhythm periodic physiological fluctuations Circadian Rhythm the biological clock regular bodily rhythms, such as of wakefulness and body temperature, that occur on a 24-hour cycle

Sleep and Dreams REM (Rapid Eye Movement) Sleep Sleep recurring sleep stage vivid dreams “paradoxical sleep” muscles are generally relaxed, but other body systems are active Sleep periodic, natural, reversible loss of consciousness

Sleep and Dreams Measuring sleep activity

Brain Waves and Sleep Stages Alpha Waves slow waves of a relaxed, awake brain Delta Waves large, slow waves of deep sleep Hallucinations false sensory experiences

Stages in a Typical Night’s Sleep 1 2 3 4 5 6 7 Sleep stages Awake Hours of sleep REM

Sleep Stages - Stage One Breathing becomes slow and even The heartbeat becomes regular Blood pressure falls Brain temperature decreases Blood flow to the brain is reduced Little or no body movement.

Sleep Stages- Stage Two Larger brain waves and occasional quick bursts of activity. The sleeper will not see anything even if the eyes are opened. A sleeper can easily be awakened by sounds. Bodily functions slow down. Blood pressure, metabolism, secretions, and cardiac activity decrease.

Sleep Stages - Stage Three Brain waves are slow (at the rate of 0.5 to 4 per second) and quite large (five times the size of waves in Stage 2). (Delta Waves) The sleeper is far more difficult to awaken as compared to stage 1 or 2 sleep. It takes a louder noise or an active attempt to wake him or her.

Sleep Stages-Stage Four The brain waves (called delta brain waves) are quite large, making a slow, jagged pattern on the EEG. The sleeper experiences virtual oblivion. If the sleeper is a sleepwalker or a bed wetter, those activities will begin in this phase. Bodily functions continue to decline to the deepest possible state of physical rest. This first period of deep sleep is the deepest. The sleeper awakened from deep sleep will probably be groggy, confused, or disoriented. "Sleep inertia" or "sleep drunkenness," seeming unable to function normally for quite some time. After the first phase of deep sleep ends, the sleeper returns to Stage 2 and then enters the REM state.

Sleep Across the Lifespan

Stages in a Typical Night’s Sleep Hours of sleep Minutes of Stage 4 and REM 1 2 3 4 5 6 7 8 10 15 20 25 Decreasing Stage 4 Increasing

Sleep Deprivation Effects of Sleep Loss fatigue impaired concentration depressed immune system greater vulnerability to accidents

Sleep Deprivation Spring time change (hour sleep loss) 2,400 2,700 2,600 2,500 2,800 Spring time change (hour sleep loss) 3,600 4,200 4000 3,800 Fall time change (hour sleep gained) Less sleep, more accidents More sleep, fewer accidents Monday before time change Monday after time change Accident frequency

Sleep Disorders Insomnia Narcolepsy Sleep Apnea persistent problems in falling or staying asleep Narcolepsy uncontrollable sleep attacks Sleep Apnea temporary cessation of breathing during sleep momentary re-awakenings

Night Terrors and Nightmares 1 2 3 4 5 6 7 Sleep stages Awake Hours of sleep REM Night Terrors occur within 2 or 3 hours of falling asleep, usually during Stage 4 high arousal-- appearance of being terrified seldom remembered

Night Terrors occur within 2 or 3 hours of falling asleep, usually during Stage 4 Person is frightened but cannot be awakened or comforted Person’s eyes are wide open but they don’t know anyone is there Person may think objects or persons in the room are scary Episode lasts from 10 to 30 minutes Can include thrashing, other violent movements Person often does not remember the episode in the morning

Theories on Dreams

I: Dreams: Psychoanalytic Theory Freud Sigmund Freud-- The Interpretation of Dreams (1900 wish fulfillment discharge otherwise unacceptable feeling Manifest Content remembered story line Latent Content underlying meaning

I: Dreams: Freud Characteristics of Dreams sequence of images, emotions, and thoughts passing through a sleeping person’s mind hallucinatory imagery discontinuities incongruities delusional acceptance of the content difficulties remembering

Wish Fulfillment Freud first to identify dreams as these kinds of fantasies life fulfillment compensatory reconciliation

II. Activation-Synthesis Theory J. Allan Hobson & Robery McCarley 1977 Physiological processes cause dreaming Limbic System: Hippocampus & Amygdala Dreams not meaningless, perhaps creative, new connections in brain

III: Information-Processing Theory A kind of problem-solving: “sleeping on it” Rehearsing stressful events

IV: Neural Housekeeping/Physiological Theory Keeping some “Files” Dumping others Synaptic connections weakened