Copyright © 2007 Pearson Education Canada 1 Body Rhythms and Mental States Chapter 5

Copyright © 2007 Pearson Education Canada 2 Chapter Outline Biological rhythms: The tides of experienceBiological rhythms: The tides of experience The rhythms of sleepThe rhythms of sleep Exploring the dream worldExploring the dream world Consciousness-altering drugsConsciousness-altering drugs The riddle of hypnosisThe riddle of hypnosis

Copyright © 2007 Pearson Education Canada 3 Biological Rhythms: Tides of Experience Understanding biological rhythmsUnderstanding biological rhythms Endogenous biological rhythmsEndogenous biological rhythms Circadian rhythmsCircadian rhythms When internal clocks are out of syncWhen internal clocks are out of sync Moods and long-term rhythmsMoods and long-term rhythms Menstrual cycles and moodsMenstrual cycles and moods

Copyright © 2007 Pearson Education Canada 4 Understanding Biological Rhythms ConsciousnessConsciousness –Awareness of oneself and the environment. Biological rhythmsBiological rhythms –A periodic, more or less regular fluctuation in a biological system; may or may not have psychological implications EntrainmentEntrainment –Biological rhythms are synchronized with external events such as changes in clock time, temperature, and daylight

Copyright © 2007 Pearson Education Canada 5 Endogenous Biological Rhythms Circadian RhythmsCircadian Rhythms –Occur about every 24 hours –Example: The sleep-wake cycle Infradian RhythmsInfradian Rhythms –Occur less often than once a day –Examples include birds migrating, bears hibernating Ultradian RhythmsUltradian Rhythms –Occur more frequently than once a day, about every 90min –Examples include stomach contractions and hormone levels

Copyright © 2007 Pearson Education Canada 6 Circadian Rhythms Occur in plants, animals, and peopleOccur in plants, animals, and people To study endogenous circadian rhythms, scientists isolate volunteers from time cuesTo study endogenous circadian rhythms, scientists isolate volunteers from time cues Suprachiasmatic nucleus (SCN)Suprachiasmatic nucleus (SCN) –Located in the hypothalamus, responsible for circadian rhythms by regulating melatonin, a hormone secreted by the pineal gland

Copyright © 2007 Pearson Education Canada 7 When Internal Clocks are Out of Sync Internal desynchronizationInternal desynchronization –A state when biological rhythms are not in phase with one another –Circadian rhythms are influenced by changes in routine. Examples include: Airplane flights across time zonesAirplane flights across time zones Adjusting to new work shiftsAdjusting to new work shifts Also, illness, stress, fatigue, excitement, drugs, and mealtimesAlso, illness, stress, fatigue, excitement, drugs, and mealtimes

Copyright © 2007 Pearson Education Canada 8 Moods and Long-term Rhythms Seasonal Affective Disorder (SAD)Seasonal Affective Disorder (SAD) –A controversial disorder in which person experiences depression during the winter and an improvement of mood in the spring –Treatment involves phototherapy or exposure to fluorescent light –Evaluating frequency of and treatment for SAD is difficult

Copyright © 2007 Pearson Education Canada 9 Menstrual Cycles and Mood Physical symptoms are commonPhysical symptoms are common –Cramps, breast tenderness and water retention Emotional symptoms are rareEmotional symptoms are rare –Irritability and depression –Fewer than 5% of women have symptoms predictably

Copyright © 2007 Pearson Education Canada 10 Why Women Overestimate “PMS” They notice depression or irritability when these moods occur premenstrually but overlook times when moods are absent premenstruallyThey notice depression or irritability when these moods occur premenstrually but overlook times when moods are absent premenstrually They attribute irritability before menstruation to PMS and attribute irritability at other times to other reasonsThey attribute irritability before menstruation to PMS and attribute irritability at other times to other reasons They are influenced by cultural attitudes and myths about menstruationThey are influenced by cultural attitudes and myths about menstruation

Copyright © 2007 Pearson Education Canada 11 Research Conclusions about “PMS” No gender differences exist in moodNo gender differences exist in mood There is no relation between stage of menstrual cycle and emotional symptomsThere is no relation between stage of menstrual cycle and emotional symptoms No consistent “PMS” pattern exists across menstrual cyclesNo consistent “PMS” pattern exists across menstrual cycles No connection exists between “PMS” and behaviourNo connection exists between “PMS” and behaviour

Copyright © 2007 Pearson Education Canada 12 The Rhythms of Sleep Why we sleepWhy we sleep Sleep deprivation & disordersSleep deprivation & disorders The realms of sleepThe realms of sleep

Copyright © 2007 Pearson Education Canada 13 Why We Sleep The exact function of sleep is uncertain but sleep appears to provide time for:The exact function of sleep is uncertain but sleep appears to provide time for: –the body to eliminate waste products from muscles –repair cells –strengthen the immune system, and –recover abilities lost during the day

Copyright © 2007 Pearson Education Canada 14 Sleep Deprivation & Disorders Sleep deprivation leads to decreases in physical and mental functioning.Sleep deprivation leads to decreases in physical and mental functioning. Sleep apneaSleep apnea –Breathing briefly stops during sleep, causing the person to choke and gasp and momentarily waken. NarcolepsyNarcolepsy –A sleep disorder involving sudden and unpredictable daytime attacks of sleepiness or lapses into REM sleep Staying up late and not allowing oneself enough sleepStaying up late and not allowing oneself enough sleep –2/3 of North Americans get fewer than recommended 8 hours

Copyright © 2007 Pearson Education Canada 15 Realms of Sleep Stage 1. Feel self drifting on the edge of consciousnessStage 1. Feel self drifting on the edge of consciousness Stage 2. Minor noises won’t disturb youStage 2. Minor noises won’t disturb you Stage 3. Breathing and pulse have slowed downStage 3. Breathing and pulse have slowed down Stage 4. Deep sleepStage 4. Deep sleep REM. Increased eye movement, loss of muscle tone and dreamingREM. Increased eye movement, loss of muscle tone and dreaming

Copyright © 2007 Pearson Education Canada 16 A Typical Night’s Sleep for a Young Adult

Copyright © 2007 Pearson Education Canada 17 Exploring the Dream World Dreams as unconscious wishesDreams as unconscious wishes Dreams as efforts to deal with problemsDreams as efforts to deal with problems Dreams as a by-product of mental housekeepingDreams as a by-product of mental housekeeping Dreams as thinkingDreams as thinking Dreams as interpreted brain activityDreams as interpreted brain activity

Copyright © 2007 Pearson Education Canada 18 Dreams as Unconscious Wishes Freud concluded that dreams provide insight into our unconsciousFreud concluded that dreams provide insight into our unconscious Manifest content includes aspects of the dream we consciously experience and latent content includes unconscious wishes and thoughts symbolized in the dreamManifest content includes aspects of the dream we consciously experience and latent content includes unconscious wishes and thoughts symbolized in the dream To understand a dream we must distinguish manifest content from latent contentTo understand a dream we must distinguish manifest content from latent content Not everything in dreams is symbolicNot everything in dreams is symbolic

Copyright © 2007 Pearson Education Canada 19 Dreams may reflect ongoing conscious issues such as concerns over relationships, work, sex or healthDreams may reflect ongoing conscious issues such as concerns over relationships, work, sex or health Dreams are more likely to contain material related to a person’s current concerns than chance would predictDreams are more likely to contain material related to a person’s current concerns than chance would predict –Example: college students and testing Males and females appear to dream about similar issues now that lives and concerns of two sexes have become more similarMales and females appear to dream about similar issues now that lives and concerns of two sexes have become more similar Dreams as Efforts to deal with Problems

Copyright © 2007 Pearson Education Canada 20 Dreams as By-product of Mental Housekeeping Unnecessary neural connections in the brain are eliminated and important ones are strengthenedUnnecessary neural connections in the brain are eliminated and important ones are strengthened The brain divides new information into “wanted” and “unwanted”The brain divides new information into “wanted” and “unwanted” What we recall as dreams are only brief snippets from scanning and sorting that occurs during REM sleepWhat we recall as dreams are only brief snippets from scanning and sorting that occurs during REM sleep

Copyright © 2007 Pearson Education Canada 21 Dreams as Thinking Dreams are a modification of the cognitive activity that goes on when we are awakeDreams are a modification of the cognitive activity that goes on when we are awake Difference between wakefulness and dreaming is that we are cut off from sensory input and bodily feedback during dreamingDifference between wakefulness and dreaming is that we are cut off from sensory input and bodily feedback during dreaming

Copyright © 2007 Pearson Education Canada 22 Dreams as Interpreted Brain Activity Activation-synthesis theoryActivation-synthesis theory –Dreaming results from the cortical synthesis and interpretation of neural signals triggered by activity in the lower part of the brain –At same time, brain regions that handle logical thought and sensation from the external world shut down

Copyright © 2007 Pearson Education Canada 23 Activations Synthesis Theory

Copyright © 2007 Pearson Education Canada 24 Consciousness-altering Drugs Classifying drugsClassifying drugs The physiology of drug effectsThe physiology of drug effects The psychology of drug effectsThe psychology of drug effects The drug debateThe drug debate

Copyright © 2007 Pearson Education Canada 25 Classifying Drugs Psychoactive drugPsychoactive drug –Substance capable of influencing perception, mood, cognition, or behaviour –Types Stimulants speed up activity in the CNSStimulants speed up activity in the CNS Depressants slow down activity in the CNSDepressants slow down activity in the CNS Opiates relieve painOpiates relieve pain Psychedelic drugs disrupt normal thought processesPsychedelic drugs disrupt normal thought processes

Copyright © 2007 Pearson Education Canada 26 The Physiology of Drug Effects Psychoactive drugs work by acting on brain neurotransmitters. These drugs can:Psychoactive drugs work by acting on brain neurotransmitters. These drugs can: –increase or decrease the release of neurotransmitters –prevent reabsorption of excess neurotransmitters by the cells that have released them –block the effects of neurotransmitters on receiving cells, or –bind to receptors that would ordinarily be triggered by a neurotransmitter or a neuromodulator

Copyright © 2007 Pearson Education Canada 27 Cocaine’s Effect on the Brain Cocaine blocks the brain’s reabsorption (“reuptake”) of the neurotransmitters dopamine and norepinephrine, so levels of these substances riseCocaine blocks the brain’s reabsorption (“reuptake”) of the neurotransmitters dopamine and norepinephrine, so levels of these substances rise –Results in an overstimulation of certain brain circuits and a brief euphoric high –When drug wears off, depletion of dopamine may cause user to “crash”

Copyright © 2007 Pearson Education Canada 28 The Psychology of Drug Effects Reactions to psychoactive drugs depend on:Reactions to psychoactive drugs depend on: –Physical factors such as body weight, metabolism, initial state of emotional arousal and physical tolerance –Experience or the number of times a person has used a drug –Environmental factors such as where and with whom one is drinking –Mental set or expectations for drug’s effects

Copyright © 2007 Pearson Education Canada 29 The Drug Debate Can we distinguish between use and abuse?Can we distinguish between use and abuse? Many ‘legal’ drugs are highly consumed e.g., coffee, tobacco, alcoholMany ‘legal’ drugs are highly consumed e.g., coffee, tobacco, alcohol Many ‘illegal’ drugs reportedly have positive or medical usesMany ‘illegal’ drugs reportedly have positive or medical uses Canadians debate over marijuana use and benefits as well as “safe-injection sites” for heroin, cocaine and other IV drugsCanadians debate over marijuana use and benefits as well as “safe-injection sites” for heroin, cocaine and other IV drugs

Copyright © 2007 Pearson Education Canada 30 The Riddle of Hypnosis Defining hypnosisDefining hypnosis The nature of hypnosisThe nature of hypnosis Theories of hypnosisTheories of hypnosis

Copyright © 2007 Pearson Education Canada 31 Defining hypnosis A procedure in which the practitioner suggests changes in the sensations, perceptions, thoughts, feelings or behaviour of the subjectA procedure in which the practitioner suggests changes in the sensations, perceptions, thoughts, feelings or behaviour of the subject

Copyright © 2007 Pearson Education Canada 32 The Nature of Hypnosis Hypnotic responsiveness depends more on the person being hypnotized than on the skill of the hypnotistHypnotic responsiveness depends more on the person being hypnotized than on the skill of the hypnotist Hypnotized people can’t be forced to do things against their willHypnotized people can’t be forced to do things against their will Feats performed under hypnosis can be performed by motivated people without hypnosisFeats performed under hypnosis can be performed by motivated people without hypnosis

Copyright © 2007 Pearson Education Canada 33 The Nature of Hypnosis Hypnosis doesn’t increase accuracy of memoryHypnosis doesn’t increase accuracy of memory Hypnosis doesn’t produce a literal re- experiencing of long-ago eventsHypnosis doesn’t produce a literal re- experiencing of long-ago events Hypnotic suggestions have been used effectively for medical and psychological purposesHypnotic suggestions have been used effectively for medical and psychological purposes

Copyright © 2007 Pearson Education Canada 34 Theories of Hypnosis Dissociation theoriesDissociation theories –Hypnosis is a split in consciousness in which one part of the mind operates independently of the rest of the consciousness, or –During hypnosis, dissociation occurs between an executive control system in the brain (probably frontal lobes) and other brain systems involved in thinking and acting

Copyright © 2007 Pearson Education Canada 35 Theories of Hypnosis Sociocognitive theoriesSociocognitive theories –Effects of hypnosis result from interaction between social influence of the hypnotist (socio) and the abilities, beliefs and expectations of the subject (cognitive) –Can explain “alien abduction” and “past-life regression