File
Transcription
File
Psychology – 8th Edition (David Myers) Chapter 7 – States of Consciousness Consciousness and Information Processing Consciousness – our awareness of ourselves and our environment Beneath the surface, our brain processes unconscious information on parallel tracks (simultaneously)… o Ex: we see a bird flying and are consciously aware of our thought processing – “It’s a hummingbird!” – but not consciously aware of our subconscious processing of the bird’s color, form, movement, distance, and identity. Theories on consciousness… o Consciousness is the result of brain activity among interconnected brain areas that crosses a threshold of intensity o Consciousness emerges from the interaction of individual brain events o Consciousness lags behind the brain activities that produce it Info processing for conscious mind – relatively slow, sequenced/serial, limited capacity at one time, but is skilled at problem solving Info processing for unconscious mind – fast, multiple/parallel tracks simultaneously Sleep and Dreams Biological rhythms – periodic physiological fluctuations – controlled by your “biological clock” Annual cycles – hibernation, migration, humans - seasonal variations in appetite/moods (seasonal affective disorder) 28-day cycles – menstrual cycle in females 24-hour cycles – varying alertness, body temperature, growth hormone secretion 90-minute cycles – various stages of sleep in 90 minute cycles The Rhythm of Sleep Circadian rhythm – the biological clock; regular bodily rhythms that occur in a 24-hour period Light, processed by the retina, signals to the brain to be alert by the production of melatonin in the pineal gland (more melatonin in the evening, and less in the morning/day) – you can buy melatonin OTC to aid with sleep. Biological clocks can be reset or disrupted by adjusting your sleeping schedule (jetlag, sleeping in too late, etc) Artificial light delays sleep 25-hour circadian rhythm Sleep Stages Sleep – periodic, natural, reversible loss of consciousness 5 distinct sleep stages – 90 minutes Awake/relaxed Alpha waves Stage 1 slowed breathing, irregular brain waves (typical of unremembered moments) may experience hallucinations – sensory experiences that occur without sensory stimuli – feeling of free falling to be awoken by a jerk Stage 2 20 minutes Periodic appearance of sleep spindles (bursts of rapid, rhythmic brain wave activity) Stage 3 Several minutes Begin to produce large delta waves – the large, slow brain waves associated with deep sleep Hard to awaken Stage 4 Combined with stage 3 to last about 30 minutes Delta waves – deep sleep Hard to awaken At the end, sleepwalking or wetting the bed may occur Sleep-talking can occur in any stage REM sleep REM sleep – rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur (also known as paradoxical sleep because the muscles are relaxed but other body systems are active.) Occurs about an hour into sleep cycles Return through stages 3 and 2 from stage 4 10 minutes of sharp, short brain waves – look like waves of stage 1 Heart rate rises, breathing quickens and becomes irregular, eyes dart around behind the lids Genitals aroused, except during very scary dreams Motor cortex is active, but blocks movement messages – essentially paralyzed – paradoxical sleep Hard to awaken Gets longer throughout the night (accounts for 20-25% of a night’s sleep) Hallucinatory dreams – vivid, story-like No snoring While in deep sleep, your brain can still process some stimuli o You can move in bed, but not fall out o You will not roll over an infant (unless intoxicated) o Occasional sounds (cars, tv, etc) will not awaken you, but sounds from a crib might o The sound of your name will alert you Everyone dreams, however everyone does not remember their dreams o 600 hrs/yr dreaming o 1500 dreams/year o 100,000 dreams/lifetime Why Do We Sleep? Not everyone needs 8 hours of sleep o Newborns spend 2/3 of the day asleep o Adults spend no more than 1/3 of the day asleep Smaller sleep differences can be genetic Sleep differences can also be cultural o Industrialized nations sleep less – light bulb, shift work, social diversions Most adults, if unhindered, would sleep 9 hrs/night = no grogginess Deprived of sleep – tired, irritable, etc Sleep Deprivation Sleep can… o Strengthen memory o Improve concentration o Boost mood o Moderate hunger and obesity o Strengthen the immune system Teenagers need about 9 hours of sleep a night, but usually get around 7… sleepiness in class Sleep deprivation can increase depression, the likelihood of accidents, and irritability, while decreasing mood, alertness and concentration Sleep Theories Several theories… o Sleep protects us (evolutionary theory) – our ancestors were better off in a cave to rest and be out of harm’ rather than try to hunt or navigate treacherous conditions in the dark o Sleep helps us recuperate – restores and repairs brain tissue; weakens unused connections between neurons o Sleep helps us remember – restores and rebuilds our fading memories of the day’s experiences; helps with creative thinking/problem solving by allowing us to “sleep on it” (incubation) o Sleep helps us grow – during sleep, the pituitary gland releases growth hormone (sleep often when young and less when older – lessened amount of growth hormone as we age) Sleep Disorders Insomnia – recurring problems in falling or staying asleep o Common quick fixes – alcohol and pills Alcohol is not helpful because it can lessen REM sleep leaving the person feeling tired the next day Pills can cause addictions which lead to higher doses and the inability to fall asleep without them. o Better trustworthy fixes Relax before sleeping in dim light (no tv or cell phones or computers) Avoid caffeine Have a regular sleep schedule Avoid naps Exercise regularly but not in the evening Reassure yourself that a little loss of sleep is not a huge deal. Hide the clock to avoid being stressed out by the time if you cannot sleep Aim for less sleep to make yourself tired Narcolepsy – uncontrollable sleep attacks; falling directly into REM sleep at inappropriate times o Lasts only about 5 minutes o 1 in 2,000 people o Brain disease – underproduction of neurotransmitters that help alertness o Can be treated with medication that stimulates alertness Sleep apnea – temporary cessations of breathing during sleep and repeated momentary awakenings o Mostly overweight men, high blood pressure o Causes irritability due to being awaken up hundreds of times in the night - less deep sleep o 1 in 20 people o Can cause snoring o Suffers may not be aware they have sleep apnea o Can be treated with weight loss or wearing a metal mask attached to a machine that pumps air into the lungs keeping the airway open Night terrors – high arousal and an appearance of being terrified; more severe than nightmares o Occur during the first few hours of sleep in stage 4, not REM when nightmares occur o Seldom remembered o Targets mostly children Sleepwalking (somnambulism) and sleep talking o Occur in stage 4 sleep o Mostly children o Genetic o As we grow older, stage 4 sleep decreases as do sleepwalking and nightmares Dreams Occur in REM sleep Dream – a sequence of images, emotions, and thoughts passing through a sleeping person’s mind; notable for hallucinatory imagery, discontinuities, and incongruities, and for the dreamer’s delusional acceptance of the content and later difficulties remembering it. o Hallucinations of the sleeping mind o Tend to involve familiar details from our lives (people, events mundane activities) Lucid dreaming –aware of dreaming while having a dream; testing the dream to see if it is a dream (trying to float in mid-air and succeeding I’m in a dream right now) Most dreams report negative emotions (rejection, sadness, fear, failure, being attacked, chased, etc) If woken in REM sleep, you can report your dream more vividly than other times. sensory input may also be present – the sound of a nearby tv, an odor, telephone ringing things that happen in the 5 minutes before slipping into sleep are typically not remembered Why Do We Dream? Regardless of the theory (listed/explained below) all sleep scientists agree that the body needs REM sleep. o If woken several times in REM sleep, you will fall back into REM sleep quicker than before (REM rebound) To satisfy our own wishes - Sigmund Freud claimed that the content of dreams represented our unconscious wishes o Freud, The Interpretation of Dreams (1900) – dreams fulfill wishes as a psychic safety valve that discharges otherwise unacceptable feelings. Manifest content – the remembered story line of a dream; sometimes involves the previous days’ experiences and events Freud - Is a censored or symbolic version of the latent content Latent content – the underlying meaning of a dream Freud - consists of unconscious drives and wishes that would be threatening if expressed directly (often sexual desires, but not represented sexually in the manifest representation) o Freud considered dreams to be the key to understanding our inner conflicts. o Scientists dismiss Freud’s theories No scientific evidence to support the claim that the manifest content represents any kind of hidden latent content Even if dreams have latent meanings, everyone can interpret these differently To file away memories – dreams allow for information processing to help sift, file, store, or discard information o People deprived of REM sleep (when dreams occur) do poorly on memory tests and other tasks than those who experience REM sleep and dreams o Students who get more REM sleep do better in school compared to those without as much sleep and REM sleep don’t cram for tests, the brain needs time to process the information with sleep/dreams To develop and preserve neural pathways – psychological function of dreams to help stimulate neural pathways that are needed and weaken those are not needed o Babies spend a good deal of time in REM sleep, possibly to help build neural pathways/networks/connections To make sense of neural static – activation-synthesis theory of dreams proposes that dreams result from the brain trying to make sense of random neural firings while sleeping o Firings in the occipital lobe can cause visions without sensory input o Firings in the limbic system can produce emotions o Firings in the frontal lobe can inhibit actions causing us to act inhibited in our dreams. To reflect cognitive development – dreams reflect maturation and cognitive development (their knowledge and understanding) Hypnosis Hypnosis – a social interaction in which one person (the hypnotist) suggests to another (the subject) that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur Popularized by Anton Mesmer (1734-1815) who would pass magnets over ailing peoples’ bodies, some of whom would fall into a trancelike (“mesmerized”) state, then awaken feeling better and improved discredited by a commission led by Benjamin Franklin when found to have no actually curing powers SNL Hypnotist skit - http://www.hulu.com/#!watch/404165 During hypnosis, the hypnotist gives a brief introduction and then presents a series of suggested experiences that range from easy to difficult. Facts and Falsehoods The power of hypnosis lies not in the hypnotist, but in the subject’s openness to suggestion Can anyone experience hypnosis? To some extent, nearly everyone is suggestible. o Ex: if told to stand with your eyes closed and sway, you will probably sway a little. 20% of people are highly suggestible – typically become engrossed in movies, novels, stories; have rich fantasy lives Anyone can be hypnotized to some degree if led to expect the results and believe in the power of the suggestions Can Hypnosis Enhance Recall of Forgotten Events? No – repressed memories uncovered in hypnosis are highly susceptible to be obtained with leading questions or suggestions from the hypnotist People who report recalling past memories and events (especially UFO abductions) are found to be highly suggestible people, often undergoing hypnosis before Can Hypnosis Force People to Act Against Their Will? 1965 study found that hypnosis could induce people to commit dangerous/involuntary acts, however it depends on the suggestibility of the hypnotized and also their conformity to orders from people in authority positions Can Hypnosis Be Therapeutic? Post hypnotic suggestions – a suggestion made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviors. o Has helped alleviate headaches, asthma, skin related disorders o Found unhelpful for helping those with drug, alcohol, or smoking addictions. Can Hypnosis Alleviate Pain? Yes – hypnosis can relieve fear which can be linked to stress and pain (dentists); hypnotized patients in surgical experiments were found to require less medication, recover sooner, and leave the hospital earlier inhibition of pain-related brain activity. Theory 1: Dissociation – a split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others. o Hypnosis can dissociate the sensation of the pain stimulus from the emotional suffering that defines the pain experience. Theory 2: The alleviation of pain can come from selective attention – not focusing on the painful stimulus (like distraction) Hypnosis does not block sensory input, but it may block our attention to and perception of the stimuli does hypnosis relieve pain by dissociating the pain sensation from conscious awareness OR does hypnosis relieve pain by distracting our attention on to other things or away from certain things? Is Hypnosis an Altered State of Consciousness? Hypnosis as a Social Phenomenon Social Influence Theory o Power of social influence o Attention guiding perception (ex: distracted attention from pain, not hypnosis, changes the perception of pain) o Imaginative actors getting caught up in playing the good hypnotism patient Hypnosis as Divided Consciousness Divided Consciousness Theory o Special state of divided alertness/consciousness Hypnosis could be explained by both theories Biological Distinctive brain activity Unconscious information processing Hypnosis as a Biopsychosocial Phenomenon Psychological Focused attention (selective attention) Expectations Heightened suggestibility Dissociation between normal sensations and conscious awareness Social-Cultural Presence of an authoritative figure in legitimate context Role-playing “good subject” Drugs and Consciousness Psychoactive drugs – a chemical substance that alters perceptions and mood Dependence and Addiction Tolerance – the diminishing effect with regular use of the same dose of a drug requiring the user to take larger and larger doses before experiencing the drug’s effect. Neuroadaption – the brain adapts its chemistry to offset the drug Withdrawal – the discomfort and distress that follows discontinuing the use of an addictive drug (aches, nausea, distress) o Physical dependence – a physiological need for a drug, marked by unpleasant withdrawal symptoms when the drug is discontinued o Psychological dependence – a psychological need to use a drug, such as to relieve negative emotions Misconceptions About Addiction Addiction – compulsive drug craving and use Addictive drugs do not lead every user to quick and chronic addiction. o 10% of people using a psychoactive drug develop addiction o People typically do not become addicted to medical drugs with psychoactive properties Addictions can be overcome individually or alone, or with the help of groups/therapy. o it depends on the individual and their needs There is debate on whether the addiction-as-disease model can be extended past drug/substance addictions and be applied to all rewarding/repetitive actions. o Can we call “gambling addictions” fed by embezzling a disease? What about extensive credit card debt due to “shopping addiction?” Psychoactive Drugs Depressants, stimulants, and hallucinogens Work at the brain’s synapses by stimulating, inhibiting, or mimicking neurotransmitters Effects also influenced by expectations Depressants Depressants – drugs that reduce neural activity and slow body functions (slow the activity in the CNS) o Alcohol, barbiturates, opiates Alcohol o Increases harmful tendencies (aggressive, sexually aggressive) o Increases helpful tendencies (leaving large tips for waiters, becoming more chatty and pleasant) o The urges you would feel if you were sober are the ones you will more likely act upon if intoxicated. o Slow reaction time, slurred speech, decreased skills, lower inhibitions o More alcohol higher blood alcohol content/level (BAC/BAL) o Large amounts of alcohol blackouts in memory because alcohol suppresses REM sleep when your day’s events become memories o Alcohol works biologically, but also is affected by expectations of drunkenness Barbiturates o Barbiturate – (tranquillizers) suppress the CNS, reduce anxiety, impair memory and judgment o Can be used as anti-anxiety drugs or sleep aids o Often consumed during suicides Opiates o Opiates – opium and its derivatives, such as morphine and heroin; lessen pain and anxiety o Can cause the brain to stop producing endorphins (natural opiates) Stimulants Stimulants – drugs that easily excite neural activity and speed up body functions o Amphetamines – drugs that stimulate neural activity causing speeded up body functions and associated energy and mood changes. Caffeine, nicotine, cocaine o Methamphetamine – a powerfully addictive drug that stimulates the CNS with speeded up body functions and associated energy and mood changes; reduces baseline dopamine levels permanent dopamine deficiency o Increase heart rate, decrease appetite (blood sugar increases), energy/self-confidence rises o Addictive, followed by a “crash” (fatigue, irritability, depression) o Cocaine Sniffed (“snorted”) or injected/smoked (“free-based”) Quick euphoria. Followed by deep crash Crack is a more potent form of cocaine (higher high, lower low) Emotional disturbance, suspiciousness/paranoia, convulsions, cardiac arrest, respiratory failure, aggression Highly addictive (studies show monkeys, rats, and cats that are addicted will push buttons thousands of times to receive cocaine or will sustain shocks to receive the drug) Its effects are also linked to expectations placebo cocaine and same results o Ecstasy – MDMA, stimulant and hallucinogen; produces euphoria and social intimacy, with risks to serotonin-producing neurons, and risks to mood and cognition Triggers the release of dopamine and serotonin, but blocks the reabsorption of serotonin A few hours of social connectedness and intimacy Dehydration, overheating, increased blood pressure, death; damage to serotonin producing neurons permanently reduced mood Hallucinogens Hallucinogens – psychedelic drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input o LSD – a powerful hallucinogenic drug; also known as acid o Effects depend on expectations – pleasure or panic Marijuana o Leaves and flowers of the hemp plant o THC – major active ingredient in marijuana, triggers a variety of effects including mild hallucinations o Smoked or eaten o Relaxes, lowers inhibitions, may produce a euphoric high; amplifies sensitivity to color, sound, taste, and smell o Effects depend on the users expectations o Can be therapeutic in relieving pain o Disrupts memory, impairs motor coordination and reaction time o Brain has special cannabinoid receptors that prove the brain naturally produces a THC pain relieving substance. o Byproducts of THC can linger in the body for months Influences on Drug Use Drug use increased in the 1970s (in the US) and has fluctuated since Biological Drug Use Psychological Social Cultural Genetic tendencies (alcoholism) Dopamine reward circuit – drug use activates the reward circuit triggering the production of dopamine signaling reward/pleasure… increased drug use = tolerance = more drugs to feel effect cycle Lacking sense of purpose or direction Significant stress and urge to avoid Psychological disorders, such as depression Cultural ethnic group Belonging to a drug using culture group Peer pressure/influence Possible channels for drug prevention for young people… Education about drugs’ negative effects Efforts to boost self esteem and purpose in life Attempts to modify peer associations, or inoculate youth against peer pressure Near Death Experiences – an altered state of consciousness reported after a close brush with death; often similar to drug-induced hallucinations Replay of memories Out-of-body sensations Vivid visions of tunnels and bright lights 1/3 of people who have had a brush with death report having a near-death experience Can the mind exist apart from the body? o Dualism – the presumption that the mind and body are two distinct entities that interact. o Monism – the presumption that mind and body are different aspects of the same thing.