Chapter 6 - States of Consciousness PDF

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States of Consciousness The Puzzle of Consciousness Consciousness is defined as our moment – to – moment awareness of ourselves and our environment  Among its characteristics, consciousness is 1. Subjective and Private – other people cannot directly known what reality is for you nor can you enter directly into their experiences 2. Dynamic (every – changing) – We drift in and out of various states throughout each day 3. Self – Reflective and Central to Our Sense of Self – the mind is aware of its own consciousness 4. Intimately Connected with the Process of Selective Attention Measuring States of Consciousness  Most common measure is Self – Report in which people describe their inner experiences  Self-reports offer the most direct insight into a person’s subjective experiences but they are not always verifiable  Physiological Measures establish the correspondence between bodily states and the mental processes  Behavioural Measures also are used including performance on specific tasks  Objective but we still must infer the person’s state of mind Levels of Consciousness  Sigmund Freud identified three levels of awareness 1. The conscious mind contains thoughts, perceptions and other mental events of which we are currently aware 2. Preconscious mental events are outside current awareness but can easily be recalled under certain conditions 3. Unconscious events cannot be brought into conscious awareness under ordinary circumstances The Cognitive Viewpoint  Reject the notion of an unconscious mind driven by instinctive urges and repressed conflicts  They view conscious and unconscious mental life as complementary forms of information processing Controlled (effortful) Processing is the voluntary use of attention and conscious effort Automatic Processing can be performed with little or no conscious effort  Occurs most often when we carry out routine actions or well – learned tasks Divided Attention is the ability to perform more than one activity as the same time The Emotional Unconscious  Results of numerous experiments have strengthened the view that unconscious processes can have an emotional and motivation flavour  Example: Researchers subliminally presented students with nouns that were either strongly negative (caner), mildly negative (Monday), mildly positive (parade) or strongly positive (friends) – later students rated their mood on standard psychological inventories – those that were shown the strongly negative words displayed saddest mood The Modular Mind  The mind is a collection of largely separate but interacting modules  These modules are information – processing subsystems within the brain that performs tasks related to sensation, perception, memory, problem solving, emotion and motor behaviour Circadian Rhythms: Our Daily Biological Clocks  Humans have adapted to a 24 – hour day – night cycle  Circadian Rhythms is when every 24 hours, our body temperature, certain hormonal secretions and other bodily functions undergo a rhythmic change that affects our mental alertness and readies our passage back and forth between states of wakefulness and sleep Keeping Time: Brain and Environment Suprachiasmatic Nuclei (SCN) are located in the hypothalamus and regulates most circadian rhythms  They link to the tiny pineal gland which secretes melatonin a hormone that has a relaxing effect on the body  SCN neurons become active during daytime and reduce the pineal gland’s secretion of melatonin, raising your body temperature and heightening alertness

Early Birds and Night Owls  Circadian rhythms influence whether we are an “early bird” or a “night owl”  Compared to night people, morning people go to bed and rise earlier and their bodily temperature, blood pressure and alertness peak earlier in the day Environmental Disruptions of Circadian Rhythms Seasonal Affective Disorder (SAD) is a cyclic tendency to become psychologically depressed during certain months of the year  Symptoms typically begin in fall or winter and then lift in spring  Many experts believed that the circadian rhythms of SAD sufferers may be particularly sensitive to light so as sunrises occur later in winter, the daily “onset” time of their circadian clocks may be pushed back to an unusual degree  Jet Lag is a sudden circadian disruption caused by flying across several time zones in one day  Night Shiftwork involves driving home in morning daylight making it harder to reset their biological clocks Sleeping and Dreaming Stages of Sleep  Approximately every 90 minutes while asleep, we cycle through different stages in which our brain activity and other physiological responses change in a generally predictable way Beta Waves take place when you are awake and alert and have a high frequency (about 15 to 30 cycles per second) but low amplitude or height Alpha Waves occur when you close your eyes and feel relaxed and drowsy; brain waves slow down to about 8 to 12 cycles per second  Sleep spindles are periodic – one to two second bursts of rapid brain-wave activity (12 to 15 cycles per second) begin to appear Stages 1 – 4 Theta Waves is when your brain – wave pattern becomes more irregular and slower – theta waves (3.5 to 7.5 cycles per second) increase    

Stage 1: A form of light sleep from which you can easily be awakened – probably spend a few minutes in this stage during which time some people experience images and sudden body jerks Stage 2: As sleep becomes deeper, sleep spindles – periodic one to two second bursts of rapid brain – wave activity begin to appear; muscles are more relaxed, your breathing and heart rate are slower and you are harder to awaken Stage 3: Mark by the regular appearance of very slow and large delta waves – as time passes, they occur more often Stage 4: When delta waves dominate the EEG pattern, you have reached stage 4 – often referred to as slowwave sleep. Your body is relaxed, activity in various parts of your brain has decreased and you are hard to awaken delta waves

REM sleep is when every half minute or so, bursts of muscular activity caused by the sleepers’ eyeballs to vigorously moved back and forth beneath their closed eyelids – because of this rapid eye movement, this stage was called REM sleep  When researchers awakened sleepers from REM periods, they discovered that a dream was almost always reported  During REM sleep, physiological arousal may increase to daytime levels, heart rate quickens, breathing becomes more rapid and irregular and brain – wave activity resembles that of active wakefulness  REM sleep paralysis is when you are “paralyzed” and unable to move Paradoxical Sleep is when your body is highly aroused, and yet it looks like you are sleeping peacefully because you move so little  REM dreams have their well – known story like quality, with vivid sensory and motor elements and the perception of reality  When you are in a REM dream, you have the experience of sensing people, objects and places of moving and behaving and witnessing and participating is a series of real events

Getting a Night’s Sleep: Brain and Environment  Areas at the base of the forebrain – basal forebrain and within the brain stem are particularly important in regulating our falling asleep  A different brain steam area – where the reticular formation passes through the pons – plays a key role in initiating REM sleep  This region contains “REM – sleep on” neurons that periodically activate other brain systems, each of which controls a different aspect of REM sleep, such as eye movements, muscular paralysis and genital arousal How Much Do We Sleep?  Newborn infants sleep an average of 16 hours a day and almost half their sleep time is in REM  As we age, three changes occur  We sleep less – on average, 15 – 24 year olds sleep an average of 8.5 hours per day and elderly adults average just under 6 hours  REM sleep decreases dramatically during infancy and early childhood but remains relatively stable thereafter  Time spent in stage 3 and 4 declines Sleep Deprivation  All three sleep deprivations had a negative impact on functioning  Mood suffered, followed by cognitive and then physical performance, although all three behaviours significant impairment from sleep loss  Student deprived of one night’s sleep performed more poorly on a critical thinking task than students allowed to sleep  In general, it takes several nights to recover from extended total sleep deprivation and we don’t make up all the sleep time that we have lost Why Do We Sleep?  According to the restoration model, sleep recharges our rundown bodies and allows us to recover from physical and mental fatigue  We need sleep to function at our emotional, mental and physical best  We need sleep to live  The biggest challenge is determining exactly what it is that “gets restored” in our bodies while we sleep  Researchers believe that a cellular waste product called adenosine plays a role  As it accumulates it influences brain systems that decrease alertness and promote sleep, signalling the body to slow down because too much cellular fuel has been burned Evolutionary/Circadian Sleep Models emphasize that sleep’s main purpose is to increase a species’ chances of survival in relation to its environmental demands Sleep Disorders Insomnia

Insomnia refers to chronic difficulty in falling asleep, staying asleep and experiencing restful sleep  Trouble falling asleep is most common among young adults and difficulty staying asleep is most common among older adults  Insomnia is the most common sleep disorder affecting approximately 10% – 40% of the population of various countries Pseudo - Insomniacs complain of insomnia but sleep normally when examined in the laboratory – awaken in the morning and claim that their insomnia was so bad that they didn’t get any sleep at all  Insomnia has biological, psychological and environmental causes  Some people are genetically predisposed to insomnia  Medical conditions, mental disorders such as anxiety and depression and many drugs can disrupt sleep  General worrying, stress at home and work, poor lifestyle habits and circadian disruptions such as jet lag and night shiftwork also trigger insomnia Narcolepsy Narcolepsy involves extreme daytime sleepiness and sudden, uncontrollable sleep attacks that may last from less than a minute to an hour  No matter how much narcoleptics rest at night, sleep attacks may occur at any time  When sleep attacks occur, narcoleptics may go right into REM stage and some of these REM stages have intense, dreamlike visual images and sounds  Also experience attacks of cataplexy, a sudden loss of muscle tone often triggered by laughter, excitement and other strong emotions  Narcoleptics report a lowered quality of life and are more prone to accidents  Scientists believed that a genetic predisposition combines with unknown environmental factors to cause narcolepsy REM – Sleep Behaviour Disorder REM – Sleep Behaviour Disorder (RBD) is the loss of muscle tone that causes normal REM sleep paralysis is absent  RBD sleepers may kick violently, throw punches, or get out of bed and move about wildly, leaving the bedroom in shambles  Many RBD patients seen in sleep clinics have injured themselves while sleeping and almost half have injured their sleeping partners Sleepwalking  Typically occurs during a stage 3 or stage 4 period of slow – wave sleep  Sleepwalkers often have blank stares and are unresponsive to other people but they seem vaguely conscious of the environment as they navigate around furniture, go the bathroom or find something to eat  Often return to bed and awaken in the morning with no memory of the event  Tendency to sleep walk may be inherited and daytime stress, alcohol, and certain illnesses and medication increase sleepwalking Nightmares and Night Terrors Nightmares are frightening dreams and virtually everyone has them Night Terrors are more intense than nightmares – the sleeper, usually a child, suddenly sit up and seem to awaken letting out a loud scream  Terrified and aroused to a near – panic state, the person might thrash about in bed or flee to another room as if trying to escape from something  Most common during deep sleep (stage ¾) and involve greatly elevated physiological arousal The Nature of Dreams – Why Do We Dream? Freud’s Psychoanalytical Theory  Freud believed that the main purpose of dreaming is wish fulfillment, the gratification of our unconscious desires and needs  These desires include sexual and aggressive urges that are too unacceptable to be consciously acknowledged and fulfilled in real life Activation – Synthesis Theory Activation – Synthesis Theory, during REM sleep the brain stem bombards our higher brain centres with random neural activity  Because we are asleep, this neural activity does not match any external sensory events but our cerebral cortex continues to perform its job of interpretation

It does this by creating a dream that provides the “best fit” to the particular pattern of activation that exists at any particular moment Cognitive Approaches Problem Solving Dream Models are dreams that can help us find creative solutions to our problems and conflict because they are not constrained by reality Cognitive – Process Dream Theories focus on the process of how we dream  Propose that dreaming and wake thought are produced by the same mental systems in the brain Toward Integration  Integration of cognitive, biological and modern psychodynamic concepts 

Drugs and Altered Consciousness Drugs and the Brain  Once the drugs are inside they alter consciousness by facilitating or inhibiting synaptic transmission How Drugs Facilitate Synaptic Transmission Agonist is a drug that increases the activity of a neurotransmitter  May enhance the production, storage or release of a neurotransmitter; activate the postsynaptic receptor or prevent the neurotransmitter from being deactivated How Drugs Inhibit Synaptic Transmission  A drug that inhibits the actions of a neurotransmitter is called an antagonist  An antagonist may reduce the synthesis, storage or release of a neurotransmitter or prevent a neurotransmitter from binding to its receptors on the postsynaptic neuron Tolerance and Withdrawal Tolerance is when the intensity of effects produced by the same dosage level decreases over time  As tolerance develops, the person must take increasingly larger doses to achieve the same physical or psychological effects  Tolerance stems from the body’s attempt to maintain a state of optimal physiological balance called homeostasis Compensatory Responses are reactions opposite to that of the drug Withdrawal is when the person experiences a strong reaction opposite to the one that the drug produced Depressants Depressants decrease nervous system activity  In moderate doses, they reduce feelings of tension and anxiety, and produce a state of relaxed euphoria Alcohol  Alcohol increases the activity of GABA, the main inhibitory neurotransmitter in the brain  By increasing the action of an inhibitory neurotransmitter, alcohol decreases brain activity  Alcohol also decreases the activity of glutamate, a major excitatory neurotransmitter, further decreasing brain activity Alcohol Myopia is a “short-sightedness” in thinking caused by the inability to pay attention to as much information as sober people Barbiturates and Tranquilizers Barbiturates are sleeping pills Tranquilizers are anti – anxiety drugs  These drugs depress the nervous system by increasing the activity of the inhibitory neurotransmitter GABA Stimulants Stimulants increase neural firing and arouse the nervous system – increase blood pressure, respiration, heart rate and overall alertness Amphetamines Amphetamines are powerful stimulants that are known as speed uppers and bennies  Prescribed to reduce appetite and fatigue, to decrease the need for sleep and sometime to reduce depression  Increase dopamine and norepinephrine activity  One form of amphetamines is crystal meth – inhaled or smoked

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 Abuse of crystal method causes irritability, insomnia, loss of REM sleep, hyperactivity, confusion, hallucinations, anxiety, paranoia and increased aggression Second form of amphetamines is MDMA – ecstasy  Primarily alters serotonin functioning by causing the release of serotonin and blocking its reuptake

Cocaine Cocaine is a powder derived from the coca plant which grows mainly in western South America  Usually inhaled or injected, it produced excitation, a sense of increased muscular strength and euphoria  Increase the activity of norepinephrine and dopamine but it does so in one major way: it blocks their reuptake  In large doses, it can produce fever, vomiting, convulsions, hallucinations and paranoid delusions Crack is a chemically converted form of cocaine that can be smoked and its effects are faster, more intense and more dangerous Opiates Opiates are drugs that are derived from opium, such as morphine, codeine and heroin  Two major effects 1. They provide pain relief 2. They cause mood changes which may include intense euphoria Oxycodone is a powerful painkiller and it rapidly became a widely abused drug because of its mood – altering effects Hallucinogens Hallucinogens are powerful mind – altering drugs that produce hallucinations  Usually distort or intensify sensory experience and can blur the boundaries between reality and fantasy  Have violent outburst, experience paranoia and panic, and have flashbacks after the “trip” has ended  Mental effects of hallucinogens are unpredictable Marijuana Marijuana is a product of the hemp plant THC (Tetrahyrdocannabinol) is marijuana’s major active ingredient, and it binds to its receptors on neurons throughout the brain  The reason for these receptor sites is because the brain produces its own THC – like substances called cannabinoids  May increase GABA activity and produces relaxing effects  THC increases dopamine activity which may account for some of its pleasurable subjective effects Hypnosis The Scientific Study of Hypnosis Hypnosis is a procedure in which “one person is guided by another to respond to suggestions for changes in subjective experience, alterations in perception, sensation, emotion, thought or behaviour” Hypnotic Induction is a process that creates a context for hypnosis Hypnotic Susceptibility Scales contain a standard series of pass/fail suggestions that are read to a subject after a hypnotic induction...