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Chapter 6.docx

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Department
Biology
Course
Biology 1001A
Professor
Tom Haffie
Semester
Fall

Description
Chapter 6: States of Consciousness (p. 206) - (1943) Swiss chemist Albert Hofmann discovered LSD - States of consciousness – pattern of subjective experience; a way of experiencing internal and external events o Altered state of consciousness – variations from normal waking state - Divisions of awareness  why you don’t fall off bed, while when you “zone out” during driving you don’t crash o Some part of you is aware The Puzzle of Consciousness - Consciousness defined: our moment-to-moment awareness of ourselves and our environment o Subjective and private. Other people can’t directly know what your reality is, and you can’t experience theirs directly either o Dynamic (ever-changing). We drift in and out of various states, but though stimuli change, consciousness is a continuously flowing “stream” of mental activity (not random perceptions/thoughts) o Self-reflective and central to our sense of self. Mind is aware of own consciousness. .: we always know that is it >> us << that is conscious of whatever our awareness is focused on o Intimately connected with the process of selective attention. Focus conscious awareness on some stimuli; shaft others Measuring States of Consciousness - Self-report most common, people describe inner experiences o Direct insight into subjective experiences (not verifiable though) - Physiological measures – correspondence between bodily states and mental processes o E.g. EEG recordings of brain activity show sleep stages o Objective, cannot tell us person’s subjective experience - Behavioural measures – performance on tasks (e.g. rouge test) o Objective, must infer subjective Levels of Consciousness: Psychodynamic and Cognitive Perspectives - Freud: 3 levels of awareness o Conscious mind has thoughts, perceptions, currently aware mental perceptions o Preconscious = outside current awareness, but can be recalled under conditions (e.g. someone says old friend’s name, you think of them though hadn’t thought of them for years) o Unconscious – cannot be brought into conscious awareness under ordinary conditions  e.g. unacceptable urges/desires stemming from instinctive sexual/aggressive drives, traumatic memories, threatening emotional conflict – kept out of conscious awareness because they cause anxiety, guilt, etc (negative emotions) - behaviourist disagree, as do cognitive/psychodynamic psychologists; research supports nonconscious influence though (e.g. placebo, split-brain patients, subliminal perceptions, etc) The Cognitive Unconscious - cognitive psychologists reject unconscious mind driven by instinctive urges/conflicts; conscious/unconscious mental life = complementary forms of information processing (un supports) Controlled vs automatic processing - controlled (effortful processing) – voluntary use of attention and conscious effort o e.g. learning driving, eating with utensils, typing  pay attention, practice makes automatic - automatic processing – performed with little or no conscious effort o i.e. routine tasks, familiar circumstances - highly complex skills can be minimum conscious thought after practice - automatic processing disadvantage: reduces chances of new ways to approach problems; effort although slower more flexible - automatic processing advantage: too much self-focused thinking hurts performance  “choking” under pressure vs autopilot o Yogi Berra “can’t think hit at same time” Divided attention - Divided attention (ability to perform more than one activity at same time) facilitated by automatic processing o E.g. talk and walk, eat and TV o If not, mental capacity overwhelmed as everything needs full attention o More difficult when tasks require same mental resources (e.g. messages in 2 earphones, “shadowing” o Negatives: people try doing too much e.g. collision rates 3x 4x with cell phone usage, slow reaction time The Emotional Unconscious - Some modern psychodynamic views use info-processing cognitive thoughts, but emotion and motivation influence behaviour unconsciously, we do/feel things can’t explain o E.g. amnesia women, pinprick, withdraw hand even after o E.g. good mood randomly? Because influenced by events in environment unconsciously o E.g. Chartrand and Bargh (1999,2000) subliminally show words, students with positive words were happiest, etc The Modular Mind - Freud and others: mind not single “entity”, but collection of separate interacting modules o Networks in brain perform tasks related to sensation, perception, memory problem solving, emotion, motor behaviour, and so on.  Independent processing, output from one can be input to another - Subjective experience of consciousness = integrated activity of modules  e.g. choir, hear everything not individual voice o .: many things affect modules .: affect consciousness state p. 210 - Consciousness refers to our moment-to-moment awareness of ourselves and the environment. It is subjective, dynamic, self-reflective, and central to our sense of identity. Selective attention focuses conscious awareness on some stimuli to the exclusion of others. - Scientists use self-report physiological, and behavioural measures to operationally define states of consciousness. - Freud believed that the mind has conscious, preconscious, and unconscious levels. He viewed the unconscious as a reservoir of unacceptable desires and repressed experiences. Cognitive psychologists view the unconscious as an information-processing system. - Controlled processing typically is required for learning new tasks. Automatic processing makes divided attention possible, enabling us to perform several tasks at once. Research on subliminal perception and other topics suggests that emotional and motivational processes also can operate nonconsciously and influence behaviour. - Many theorists propose that the mind consists of separate but interacting information processing modules. Our subjective experience of “unitary” consciousness arises from the integrated output of these modules. Circadian Rhythms: Our Daily Biological Clock - Every 24 hours temperature, some hormones, bodily functions undergo a rhythmic change affecting mental alertness and readies our passage back and forth between states of wakefulness and sleep  daily cycle called circadian rhythm Keeping Time: Brain and Environment - CR regulated by superchiasmatic nuclei (SCN) in hypothalamus (ie = brain’s clock) o Transplantable o Genetically programmed cycle of activity/inactivity o Linked to tiny pineal gland, which secretes melatonin (hormone that has relaxing effect on body) o Active in day, reduce pineal gland secretion, raising body temp and alertness; vice versa - Environment keeps SCN neurons on 24 hour schedule o Eyes neural connections to SCN .: light of day increases SCN activity, resets clock o Isolated SCNs drift into longer natural cycle (24.2 – 24.8 = free running circadian rhythm)  Can extend even longer, going to bed later and later each day if isolated; forcing it = sleep problems  E.f. 1989 New Mexico Follini Early Birds and Night Owls - Early birds peak earlier than night owls Environmental Disruptions of Circadian Rhythms - Gradual / sudden environmental changes can disrupt CR - Seasonal affective disorder (SAD) = cyclic tendency to become psychologically depressed during certain months of the year o Symptoms start fall/winter (shorter daylight), lift in spring  Experts: because CR of SAD sufferers sensitive to light .: wake up still sleepy - Jet lag – flying across several time zones in 1 day o Causes insomnia, decreased alertness, poor performance o Travelling west easier because lengthening travel day more compatible with natural free-running circadian cycle o Body naturally adjust 1 hour/day - Night shiftwork, problem o Driving home morning resets clock o Off-days fall back into day-night schedule to spend time with family, disrupting CR adjustments - 12 am – 6 am  biological clocks promote sleepiness here Psychological Applications: Combatting Winter Depression, Jet Lag, and Night Shiftwork Disruptions - Controlling Exposure to Light o Treating SAD  Phototherapy – properly timed exposure to bright artificial light  Can shift CR 2-3 hours per day  Dawn simulation – light gradually increases  .: sunlight not temp more affects SAD o Reducing Jet Lag  Flying east, fall behind .: light in morning; avoid light later  Flying west, ahead of local time.: avoid light in morning; get light afternoon/evening o Adjusting to Nightwork  Maintain schedule on days off  Bright lights in work  Dark quiet room for sleep o Melatonin Treatment: Uses and Cautions  Can shift CR 30-60 min /day  Not legal in Canada without prescription; US diet supplement  Tablets way too high doses o Regulating Activity Schedules  Easier to extend working day than compress it p. 214 - Circadian rhythms are 24-hour biological cycles that help regulate many bodily processes. The suprachiasmatic nuclei (SCN) are the brain’s master circadian clock. Environmental factors such as the day-night cycle, help to reset our daily clocks to a 24-hour schedule. - Circadian rhythms influence whether we are a “morning person” or a “night person” - Seasonal affective disorder (SAD), jet lag, and night shiftwork involve environmental disruptions of circadian rhythms. Treatments for circadian disruptions include controlling exposure to light, oral melatonin, and regulating daily activity schedules. Sleep and Dreaming - CR does not regulate sleep directly, but decreases nighttime alertness to promote readiness for sleep Stages of Sleep - Every 90 minutes asleep, cycle through stages (brain and other physiological responses) - EEG of brain activity shows pattern of beta waves when awake/alert, 15-30 cps, low amplitude o Relaxed/drowsy – alpha waves 8 to 12 cps Stage 1 through Stage 4 - Stage 1 o Brain-wave pattern irregular as sleep begins  theta waves (3.5 to 7.5 cps) increase o Light sleep easily awakened from o Few minutes or less o Images, sudden body jerks - Stage 2 o Sleep spindles (1 to 2 second bursts of rapid brain-wave activity (12 to 15 cps) o Muscles more relaxed, breathing/heartrate slower, harder to awaken - Stage 3 o Regular appearance of very slow (0.5 to 2 cps) and large delta waves - Stage 4 o Delta waves dominate EEG pattern - Slow wave sleep = stage 3 and 4 o Body relaxed, activity in various brain parts decreased, hard to awaken - 20-30 min later, EEG goes to 3, .: 1-2-3-4-3-2 (total: 60-90 minutes) REM Sleep - (1953) Eugene Aserinsky and Nathaniel Leitman, University Chicago - Every 30 seconds, rapid eye movements - If awakened, almost always dreaming (even if say never have dreams) - Physiological arousal may increase to daytime levels (heartrate quickens, breathing faster/irregular, brain wave active, erections/lubrication) - Brain signals make difficult for voluntary muscle contractions .: arms, legs, torso relax - Sleep paralysis / paradoxical sleep - Mental activity in all sleep - REM dreams: story-like, real - Non-REM dreams: shorter, less story, fixed (tableau without plot) - Sleep-thoughts (in non-REM sleep) because closer resemblance to daytime thinking, just simple and jumbled Getting a Night’s Sleep: Brain and Environment - No sleep centre in brain  stages controlled by different mechanisms - Sleep not “turning off” wakefulness regulators, but “turning on” sleep regulators - Base of forebrain (basal forebrain) in brain stem  important o Diff brainstem area (where reticular formation passes through pons – REM sleep ON neurons that periodically activate other brain systems which control different aspects of REM (eye movements, muscular paralysis, genital arousal) - Environment key o Seasons: fall/winger 15-60 minutes longer sleep o Shiftwork, jetlag, stress, noise hinders sleep quality (even “sleeping through noise” reduces time in good sleep) How Much Do We Sleep? - 4-5 REMs per night average - Age changes: o We sleep less – 19 to 30 = 8; elders 6 hours o REM sleep decreases then stable o Stage 3 and 4 time decrease o Varies between individuals significantly e.g. young adults 2/3 = 6.5-8.5, 1% > 10, 1% < 5 Short- and Long-Sleepers - Some people need more sleep; others need less - E.g. famous people 3 to 5.5 hours per night, sometimes nap; e.g. 70 year old 1 hour night From Genes to Lifestyles - Genetics influence long versus short sleepers, more or less in REM, more or less short wave sleep - Lifestyles: day vs night, pressure vs chill lives, noisy vs quiet sleeping environments - Central and South America / Mediterranean = 1-2 hour naps reducing night sleep Sleep Deprivation - Half Americans work not sleep, millions disordered - Short term total sleep deprivation (45 hours) - Long-term total sleep deprivation (>45 hours) - Partial deprivation (< 5 per night) - Mood, mental tasks, physical tasks o Average scores like bottom 9% of regulars o All suffered significantly in order: mood, mental, physical (least) - Think you are fine but critical thinking bad - Randy Gardner (17 year old, 1964, San Diego) 11 days awake Why Do We Sleep? - Restoration model, sleep recharges run-down bodies (physical / mental fatigue recovery) o Emotional, mental, physical best...LIFE (e.g. rats) needs sleep o Sleep 10 minutes longer on days we exercise - Adenosine o produced as cells consume fuel o accumulates and influences brain systems that decrease alertness / promote sleep, signalling body slow down (too much fuel burned)  caffeine similar structure blocks receptor sites - evolutionary/circadian sleep models o main purpose to increase species’ survival regarding environment  e.g. humans alive at night = eaten; day is when hunt, food gathering, traveling .: sleep at night  e.g. small prey hide sleep safe way .: sleep more  e.g. big prey sleep exposed .: sleep less o sleep conserves energy (10 to 25% slower metabolic rate while sleeping) o REM-rebound effect – tendency to increase REP sleep after deprived of it - REM vital for mental functioning, especially memory consolidation o High levels of brain activity strengthen neural circuits in remembering important information learned that day o Brain waking activity influences REM activity (e.g. reaction time activity = that brain activity in REM) o E.g. After Christmas exams, more REM Sleep Disorders - ½ to 2/3 Americans say problems Insomnia - Insomnia refers to chronic difficulty in falling asleep, staying asleep, experiencing restful sleep o Falling asleep problems common in youths; staying asleep common in adults - Most common sleep disorder (10 to 40% population) - Pseudoinsomniacs complain of insomnia but sleep fine; insomniacs also overestimate o After fine night, some claim no sleep! - Causes (bio, psychological, environmental) o Genetically disposed, and medical conditions, mental disorders (anxiety/depression), drugs, worrying, stress, poor lifestyle habits, circadian disruptions (jet lag, night shiftwork) disrupt - Non-drug treatments: o Stimulus control: (learning) condition body to associate stimuli in sleep environment (e.g. bed) with sleep  E.g. when awake no bedroom, if no sleep in 10 minutes leave bedroom and come back Improve Sleep - Regular pattern (CR) - Avoid sleeping in, regardless - Avoid naps - Don’t eat before sleep (or light, or L-tryptophan  serotonin) - Avoid stimulants - Avoid alcohol and sleeping pills (impairs REM) - Be relaxed in bed - Avoid exercise before bed - Avoid non-sleeping stuff in bedroom Narcolepsy - Narcolepsy = extreme daytime sleepiness and sudden, uncontrollable sleep attacks, last 1 to 60 min o Regardless of sleep previous night o 1/1000 people - Attacks = straight into REM stage - Cataplexy: loss muscle tone triggered by strong emotions (laughter, excitement, etc) o Abnormal version of REM normal muscle paralysis o .: narcolepsy = disorder where REM fronts on awake time - 75% narcs sleep driving, 12% nonnarcs - 1 twin narc, other 30% likely o .: genetic and environmental (unknown) o No cure, stimulant drugs reduce sleepiness and antidepressants (suppress REM) decrease cataplexy  Daytime naps help, positives alertness last few hours though REM-Sleep Behaviour Disorder - REM-sleep behaviour disorder (RBD): normal loss of muscle tone in REM paralysis absent, .: act out dreams o Kick, punch, jump, hurt themselves and half hurt partner o Brain abnormalities prevent signals that normally inhibit movement during REM from being sent (hypothesis) Sleep Apnea - Sleep apnea = stop restart breathing repeatedly in sleep - Stoppages 20-40 seconds, can be 1-2 minutes - Severe: 400-500 times per night - Caused by obstruction in upper airways (e.g. sagging tissue since muscles lose tone in sleep) - Chest/abdomen move, but no air through lungs o .: reflex and person gasps/startling snore, then awake for few seconds - 1-5% world - Surgery can remove obstruction, also treated by masks pumping air continuously - Stresses heart, hypertension, daytime sleepiness, higher car accidents Sleepwalking - Stage 3 or 4 of slow-wave sleep - Blank stares, unresponsive to others, vaguely conscious of environment (so can do things i.e. not hit furniture, washroom, eat) - Return to bed, wake up not remembering - 10-30% children do it once, less than 5% adults (if not as child, < 1% as adult) - Caused by: genes, stress, alcohol, certain illnesses, meds - Treatments: psychotherapy, hypnosis, drugs, wake up often, mostly just wait until outgrow it Nightmares and Night Terrors - Nightmares occur more often during REM and in hours closer to wakeup; physiological arousal same as with pleasant dreams - Night terrors (aka sleep terrors) more intense – child sits up awake screaming, terrified, panic, thrash or flee like escaping o Don’t remember next day o If made fully conscious, images / sense of danger (choking, attacking etc) o Most common during stages 3-4, high physiological arousal (double/triple heartrate) o 6% children; 1-2% adults; wait for kids to grow up The Nature of Dreams - Aboriginal Australians – dreams = “parallel” reality connecting to spiritual world and collective unconscious to ancestral past o Creation, belief, oral passing to generation - Other cultural identifies Senoi Malaysia = events in dreaming and waking life influence one another) When Do We Dream? - Mental activity throughout sleepcycle - Hypnagogic state (transitional state from wake to through early stage 2 sleep) continues, mental activity more dreamlike - 15-40% sleepers report dreamlike activity when awakened 6 minutes after falling asleep; 25% visual image 45 seconds later - More dreaming when brain more active (ie during REM vs non-REM) – 80% vs 15-50% o Higher final hours sleep than earlier (circadian sleep-wake cycle prepares us to rise) What Do We Dream About? - 35 years of research, coding system by Calvin Hall, Robert Van de Castle  dreams familiar settings, involve people we know - Flying dreams uncommon but bizarre so we remember - 80% dreams negative, 50% aggressive, 33% misfortune - Males 2/3 male; woman even - 50% dream contain some content reflecting experiences of our most recent day Why Do We Dream? Freud’s psychoanalytic theory - Wish fulfillment = gratification of our unconscious desires and needs o E.g. sexual and aggressive urges too unacceptable to talk acknowledge/fulfill in real life - Manifest content = “surface” story - Latent content = disguised psychological meaning (e.g. train, sex) - Dream work = process which dream’s latent content transformed to manifest content (e.g. symbols, characters combining features of real people) - .: you’re satisfied secretly so you’re peaceful and not anxious - Criticisms: subjective, no evidence Activation-synthesis theory - No purpose - (1977) J. Allan Hobson, Robert McCarley: physiological theory - During REM, brain stem bombards higher brain with random neural activity (activation), but doesn’t match sensory events (we’re asleep) and cerebral cortex continues job of interpretation  creates “best fit” dream (synthesis) o Trying to make sense of random neural activity, and since memories/experiences influence stories, seems like meaning - Critics: overestimates bizarreness, assumes REM unique activity causes, ignores non-REM dreams; still has support Cognitive approaches - Problem-solving dream models : dreams help us find creative solution to problems and conflicts because not restricted by reality o Critics: having problem in dream / thinking about dream after wake up does not equal solving problem IN dream - Cognitive-process dream theories: process of how we dream, based o modula model of consciousness = dreaming/waking same mental systems o .: why 3-4 year olds don’t dream in REM, 8-9 year olds do a little  dreaming requires imagery skills and other cognitive abilities that aren’t developed o .: developing mental abilities with age develops dream abilities - Rapid shifting of attention is a process common to dreaming and waking mental activity; dream/wake more similar than we thought Toward integration - Antrobus (1991) theory is mix: modules interact like awake. Reticular formation stimulates during REM (motivational, cognitive, emotional, perceptual) o Input from sensory IN inhibited; most motor module responses OUT also inhibited (besides respiration and eye movements) o .: brain gives best fit for internally generated images - Seymour Epstein (1999): also unconscious mind info processor integrating modules, but not wish fulfillment but emotional/motivational and cognitive o Extensions of waking though Daydreams and Waking Fantasies - Fantasy-prone personality: people live in vivid, rich fantasy world they control (2-4% population) o Mostly female o ¾ of people orgasm by fantasy, all experience real in 5 senses - Daydreams less vivid, emotional, weird but more imagery o Personal concerns  Similar to nighttime dreams .: nightdreams extension of waking thought p. 229 - EEG measurements of brain activity indicate five main stages of sleep. Stages 1 and 2 are lighter sleep, and stages 3 and 4 are deeper, slow-wave sleep. High physiological arousal and periods of rapid eye movements characterize the fifth stage, REM sleep. Several brain regions, including brain stem, regulate sleep. - Amount we sleep nightly changes as we age. Genetic, psychological, environmental factors affect our sleep patterns and sleep length. - Sleep deprivation negatively affects mood, mental performance, and physical performance. The restoration model proposes that we sleep to recover from accumulated mental and physical fatigue. Evolutionarylcircadian models state that species evolved unique waking- sleeping cycles that maximized their changes of survival. - Insomnia is the most common sleep disorder, but less common disorders such as narcolepsy, REM-sleep behaviour disorder, and sleep apnea can have extremely serious consequences. Sleepwalking typically occurs during slow-wave sleep, whereas nightmares occur most often during REM sleep. Night terrors create a near-panic state of arousal, typically occur in slow-wave sleep, and are most
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