Ch. 6: Consciousness

3 Levels of Consciousness Conscious: awareness of what’s going on in and around us You are aware of your dog locking your hand. Subconscious: just below awareness You feel uncomfortable, but aren’t aware that it is because your friend is treating you differently. Unconscious: no awareness You make it home without any awareness of how you got there.

Biological Clock Body temperature Kidneys Sleep-wake cycle

Sleep-Wake Entrainment and circadian rhythm The human body has a natural free-run rhythm of 25 hours – we have to function on 24! Our bodies hit a low point between 3am and 5am – low body temp, blood pressure, etc. Can change circadian rhythm, kind of, but takes months.

The Body and Sleep The first hour of sleep is the deepest with dramatic fall in heart rate, blood pressure, breathing, etc. When we sleep, body makes new cells, brain chemicals are restored, body hair grows.

REM Sleep Happens 4-5 times a night (every 90 minutes); brain activity, blood pressure, heart rate, breathing all spike. Body is paralyzed. Dreams last 5-40 minutes. REM happens when we are not in deep sleep and each REM lasts longer than the one before. Sleep gets lighter.

3 types of brain waves Beta waves: rapid brain waves; appear when a person is awake. Alpha waves: fairly relaxed brain waves that occur in stage 1, just before we go to sleep. Delta waves: slow, lazy, deep-sleep brain waves. After about an hour of sleep, you reach delta/stage 4 and begin to move back toward stage 1. Instead of reaching stage 1, you go into REM.

NREM Sleep Sleep involving partial thoughts, images, or stories that are poorly organized. NREM is all the sleep below REM. In adolescents, growth hormone is secreted during deep NREM sleep.

3 hypotheses for dreams 1st hypothesis – process information - dreams get the brain reorganized after the day. Keeps brain busy while it recharges. 2nd hypothesis – unsolved problems - dreams help solve problems from the day. 3rd hypothesis – make sense of random stimulation - dreams make sense of the random stuff the brain is sorting through and organizing.

Freud and dreams Freud believed dreams were symbolic expressions of our unconscious conflicts.

Dream Themes Most dreams are about very ordinary events. 70% of our dreams are about people we know. 40% of females and 27% of males dream about bodies of water. Common themes are: falling, being chased, sex and romance, violence, talking to dead friends or relatives, shoplifting, being naked in public, and discovering the secret of the universe.

Nightmares About 5% of people have them as often as once a week. More common when REM has been missed (because you have more dreams) Nightmares happen to everyone and are normal.

Night Terrors Unexpectedness of it sends bodily processes zooming, heart rate to 170+, feeling of choking, panic, and fear of dying. Fairly common in young children. When they occur in adults, usually something is physically wrong.

How much sleep? People differ, but we generally need 7-8 hours of sleep. Almost no one can get by with less than 5 regularly. Teens need 8-9 hours. Many people sleep less nowadays in order to do more, leading to more mental confusion and accidents. After 11 hours, our brain functions drowsily.

Sleep walking and talking When random electrical impulses hit speech and movement areas of brain, you sometimes walk or talk. This is not abnormal. Usually happens during deep stage 4 NREM.

Sleep problems About 10% of adult Americans have trouble sleeping. Usually self-created problem. Biggest causes are being out of circadian cycle and taking drugs or alcohol. Drugs (including sleeping pills) block REM sleep. Heavy extended alcohol use can cause such severe REM rebound that dreams appear while awake.

Hypnosis The brain has the power to control incoming stimulation – tune things out, focus on things, etc. Hypnotists use the power of suggestion to help focus on or block out certain things. Anything we can do with hypnosis we can also do without it. Some people just don’t have the confidence to do it.

Meditation Can help lower blood pressure and slow heart rate.