Consciousness
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Transcript of Consciousness
Consciousness
Chapter 7 – Myers Psychology
Levels of Consciousness •Normal or waking Consciousness – active conscious that you are currently thinking about•Preconscious – information that is not conscious but is retrievable into conscious awareness•Non-conscious: we are unaware of it happening–Heartbeat, breathing, etc.
Consciousness – continued
Unconscious level • Sigmund Freud - Psychoanalytic approach• Repressed thoughts and feelings drive behaviors
– Difficult/impossible to prove (not widely accepted)
Subconscious level • Information that we are not consciously aware of but we know
must exist due to behavior– Mere exposure effect
Altered States
Anything that enhances or diminishes consciousness
Drugs, supplements, deprivation of sustenance…
Most common is SLEEP
Sleep
• Sleep is a behavior and an altered state of consciousness
• Fast Facts: – 1/3 of lifetime (25 years) spent in sleep• 6 of these 25 are spent dreaming (approx. 100,000 dreams in a
lifetime)– Need for sleep varies (20 hours for infants)– Every animal sleeps
Theories of Sleep • Protects
• Our sleep suits our ecological niche – fits our environment• Hides us from harm; animals with least fear of predation sleep
least
• Restorative• Conserving energy for daylight hours, recuperating from
exhaustion/stress• Literally repairing neurons (weaken unused connections and
strength others)
Theories of Sleep - continued
• Remembering• Restores and rebuilds our fading memories of the day’s
experiences• Increases creative thinking
• Growth process• Pituitary releases growth hormones
Biological Rhythms
• Defn: periodic physiological fluctuations
• Annual cycles – migration, hibernation, humans – experience seasonal variations in appetite, sleep length, and moods– SAD(Seasonal Affective Disorder) – people become
depressed at the same time of year
Biological Rhythms – continued
• 28-day cycles – menstrual cycle
• 24-hour cycle – varying and falling alertness, body temperature, and growth hormone secretion.
• 90-minute cycle – cycle through various stages of sleep.
Circadian Rhythm• the “biological clock” • Regular body rhythms (body temp, and wakefulness
for example) that occur on a 24-hour cycle– High alertness portion of this cycle shifts as we age
(“owls” “larks”)• Retirement homes vs. dorms
Circadian Rhythm – Continued • Jet Lag – crossing time zones
– Spend the 1st day outdoors – helps you assimilate
• Shift work sleep disorder – work hours overlap normal sleep hours can lead to insomnia
• Suprachiasmatic Nucleus – pair of pinhead-sized clusters of 20,000 cells that control the circadian clock, located In hypothalamus – Partly does this by causing pineal gland to regulate melatonin
Stages of Sleep (repeats ~ every 90 minutes)
“Quiet sleep”- NREM (Non-Rapid Eye Movement)•Stage 0 (Awake, relaxed): relaxed with eyes closed
– You don’t know when you fall asleep (characteristic of sleep – state you don’t know you are in until you are out)
– But, an EEG will show exactly when you fell asleep• alpha waves
Stages of Sleep NREM, continued
• Stage 1: 30 seconds – 10 minutes– theta waves– hypnagogic (hypnic) jerks (usually falling or floating)– other hallucinations – false sensory experiences; seeing
something in the absence of an external visual stimulus
• Stage 2: 40-50% of sleep, 20 minutes– sleep spindles – bursts of rapid, rhythmic brain activity– sleep talking possible during this or later stages
• Stage 3: transition stage– beginning of delta waves (“slow-wave sleep” = stages 3
and 4)
Stages of Sleep NREM, continued
• Stage 4: about 30 minutes, decreases as night goes on– deep sleep, 20-50% delta waves, brain responds to
sounds– Sleepwalking and bedwetting
Function of Non-REM sleep:– Body tissues are restored, pituitary releases growth
hormone, body re-energizes
Stages of Sleep NREM, continued
Sleep Cycle
Stage 1 Stage 2 Stage 3 Stage 4 Stage 3 Stage 2 Stage 1 REM
(repeat)
REM Sleep • Resembles nearly-awake stage 1 sleep• Heart rate and breathing increase, approx. every ½ minute your eyes
dart around• Nearly all dreams occur in REM
• Vivid and story-like• 25% of night’s sleep (approx. 100 min per night)• temporary paralysis
Function of REM Sleep
• Necessity demonstrated by “REM Rebound”– Intoxication increases SWS (Slow-wave sleep) Stage 4,
resulting in REM Suppression – After removal of suppressant, rebound occurs
• hormones are released that counteract fatigue, irritability, and inattention
• Nervous system development (provided neural stimulation needed)
• Memory consolidation (esp. procedural memory)
Sleep Duration
• Take a one minute to think and write:– How much sleep is necessary? Explain your
thoughts.
Sleep Duration – Continued • What accounts for differences among individuals?– Genetics (identical twins more similar than fraternal)– Cultural (2001 Gallup avg = 6.7 / night, 1942 avg. = 7.6
hours)Sleep Debt: your body is not forgiving!
Age & Condition Avg. Sleep per Day
Newborn Up to 18 hours
1-12 months 14-18 hours
1-3 Years 12-15 hours
3-5 Years 11-13 hours
5-12 Years 9-11 hours
Adolescents 9-10 hours
Adults + elderly 7-8(+) hours
Pregnant women 8(+) hours
Effects of Sleep Deprivation – Causes problems with• Confusion• Attention - Causing accidents
– Chernobyl, Exxon Valdez, Three Mile Island accidents, BP oil spill• Misperceptions• Hand tremors, droopy eye-lids, focusing, sensitivity to pain• Suppressed immune systems (even cancer – people who sleep 7-
8 hours per night outlive the sleep deprived).
http://abcnews.go.com/WNT/video/sleep-deprivation-observed-21-volunteers-16120599
Sleep Deprivation - Continued
• Randy Gardner - 1964– 17 year old high school student– 264 hours (about 11 days), no stimulants• Wanted to show that he could break the record without
negative consequences. • Day 4 he thought a street sign was a person. • Day 11 he was asked by a reporter to continually subtract 7
starting with 100. He stopped at 65, and said he forgot what he was doing.
Sleep Deprivation
• Peter Tripp - 1950s disc jockey – 201 hour wake-a-thon, used some drugs (controlled
by psychiatrists)• https://www.youtube.com/watch?v=ko9MdrVW
vHM
Sleep Disorders • Dyssomnias – sleeping disorders that make it difficult to get
to (or remain) asleep – insomnia, sleep apnea, alcohol-dependent sleep disorder
– Insomnia – Recurring problems in falling or staying asleep• Onset Insomnia – Takes a long time (30 + min) to fall asleep• Maintenance Insomnia – awakening after a short period of sleep• Early Morning Awakening – 30-60 before person intends to rise
• Often worsened by worry over sleep loss
Sleep Disorders - Continued
– Sleeping pills and alcohol trigger SWS, not REM, so it just makes it worse.
Solutions? – Relax before you go to bed– Avoid caffeine– Exercise regularly (not late at night)– Sleep on a regular schedule
• Sleep apnea – temporary cessations of breathing during sleep – causes wakefulness– 1 in 20 people– Serious cases require a mask-like device to open airways
• Narcolepsy – uncontrollable sleep attacks (often directly in to REM sleep)– Narcoleptic Dog (
https://www.youtube.com/watch?v=-zVCYdrw-1o)
Sleep Disorders - Continued
Sleep Disorders – continued
• Parasomnias – involve abnormal movements, behaviors, emotions, perceptions, and dreams that occur while falling asleep, sleeping:– Bruxism – severe teeth grinding– Restless Legs Syndrome (RLS)– Somnambulism (Sleepwalking)– SIDS (crib death)– Jet Lag
Sleep Disorders - continued
• Night terrors – high arousal and appearance of being terrified; Stage 4, seldom remembered.
• Nightmares v. Night terrors– Mares – unpleasant dreams, REM sleep, memories– Terrors – physical symptoms, Stage 4, no memori