PSYC 100 Ch. 5 Textbook Notes.docx

CHAPTER 5: VARIATION IN CONSCIOUSNESS - Somniloquy: talk while sleeping - Narcolepsy: serious sleep disorder; sleep uncontrollably while doing everyday routine - Figure: William Dement- sleep disorder is the only disorder that is caused by a flaw in the primary sleep systems in the brain - sleep deprivation has been linked to various negative outcomes (negative emotional stimuli) - sufficient sleep is critical to well-being 1) THE NATURE OF CONSCIOUSNESS - Consciousness: awareness of external and internal stimuli - Figure: William James – stream of consciousness because our consciousness is constantly changing 1.1 Variations in Awareness and Control - Koch and Tsuchiya: can have either attention or consciousness - Mind wandering concept: people’s experience of task-unrelated thoughts -- thoughts that are unrelated to what they are trying to do at the moment - Automatic Process: happens without intentional control or effort - Controlled Process: happens with intentional control or effort - Figure: Malcolm Gladwell with his book of Blink- how effortlessly some judgments and choices seem to be made 1.2 Unconscious Thought Effects >Theory of Unconscious Thought: - proposed by Ap Dijksterhuis of University of Amsterdam - when people are unconscious, the decision made will be better than when they are conscious - Attention is the key to distinguish between conscious and unconscious thought - conscious is a thought with attention while unconsciousness is a decision without attention -unconscious thought is said to be better because it doesn’t have information constraint compared to conscious thought 1.3 Consciousness and Brain Activity - consciousness doesn’t originate from brain structure, but rather from activity in distributed network of neural pathway - brain imaging method: explore level of brain activity and consciousness -- through EEG: monitor brain electrical activity over time as the purpose to record by attaching electrodes to the scalp surface -- summarize line tracing known as brain-wave (they vary in height and frequency) - brain wave is divided into 4 principal bands : alpha (relaxing), beta (problem-solving), delta (dreamless sleep), theta (light sleep) 2) BIOLOGICAL RHYTMS AND SLEEP - Kenton Crocker- sleep was originally thought as the absence of phenomena -- all activities become inactive -William Dement of Stanford University: transform the lab research for sleep from study of dreams to the study of the nature of sleep - Joseph de Koninck – important links between sleep quality and the body’s natural rhythm - Biological rhythm: periodic fluctuations in physiological functioning 2.1 The Role of Circadian Rhythms - Circadian rhythm: 24 hour biological clock found in human and other species - Influence: regulation of sleep, blood pressure, urine production, hormonal secretion, alertness, short-term memory - Without exposure to light, circa cycles run longer (24.2) because daily exposure to light readjust people’s biological clocks -during the exposure, retina send inputs to small structure in hypothalamus called suprachiasmatic neucleus (SNC) - Ralph Mistlberger and Mary Harrington- SCN send signals to pineal gland whose secretion of melatonin plays a key role in adjusting biological clocks - Benjamin Rustak- mammalian circa system is more complex 2.2 Ignoring Circadian Rhythms - William Dement: sleep debt must be paid by hours missed - getting out of sync also means jet lag - when fly westward the adjustment is easier (because the day is longer) and fly eastward is harder (because the day is shorter) 2.3 Melatonin and Circadian Rhythms - Melatonin is said to regulate human biological clock (but the finding isn’t consistent) - contributing by the fact that it is difficult to optimize the right timing for melatonin intake 3) THE SLEEP AND WAKING CYCLE - sleep is generally thought as the phase of shut down - devices used to study sleeping phenomena: EEG (electroencephalograph), electromyography (EMG) which records muscular activity and tensions, electrooculograph (EOG) which records eye movements -- other instruments: monitor heart rate, breathing, pulse rate and body temperature 3.1 Cycling through the Stage of Sleep - there 5 stages during sleep 3.1.A Stages 1-4 - Stage 1: brief transitional stage of light sleep that lasts for 1-7 mins (alpha dominates) -- breathing and heart rate slow as muscle tension and body temperature decline -- alpha gives way to theta (light sleep) -- Hypnic jerks: brief muscular contractions occur as people fall asleep - Stage 2: brief bursts (higher frequency brain waves) called sleep spindles occur. Period: 10- 25 mins -- amplitude becomes higher and slower in frequency -- gradually descend into deep sleep (delta comes in) - Stage 3 and 4 (DEEP SLEEP) - slow-wave sleep consists of 3 and 4 where high amplitude, lower frequency, delta waves dominate - period: 30 minutes Then the recycle reverses 3.1th REM sleep - 5 stage: rapid eye movement (REM) where EOG is used - Nathaniel Kleitman and REM term coined by William Dement - REM is the deep stage of sleep where muscle movement is minimal (paralyzed) irregular breathing and pulse rate - dreams mostly occur at this stage - Carlyle Smith: brain activity during sleep consolidates information during the day and different stages of sleep may be implicated by different types of tasks or information -- Stage 2: consolidate procedural motor-type tasks -- REM: important for complex logic-type tasks Conclusion - REM: deep stage of sleep, rapid eye movement, high frequency, low-amplitude and vivid dreaming - Non-REM (NREM): consists 1-4, absence of REM, little dreaming and varied EEG activity 3.2 Repeating the Cycle - rsteated 4 times - 1 REM is short and gets longer (40-60 mins) - on contrary: NREM becomes shorter 3.3 Age Trends in Sleep - 2 types of sleep: REM and NREM - infant spends longer REM but decreases from 50% to about 20% as they grow - young adults need more sleeps - elderly needs less sleep 3.4 Culture and Sleep - sleep does not vary from culture - co-sleeping: family sleeping together (in Japan) 3.5 Neural Bases of Sleep - subcortial structures that lie deep within the brain is responsible for regulating sleep rhythm and waking - reticular information is in the core of the brainstem (responsible for wakefulness and sleep) - Ascending reticular activating system (ARAS) consists of afferent fibers running through the reticular formation that influence physiological arousal Other brain structures: - pons and adjacent areas in the midbrain: critical to the generation of REM sleep - hypothalamus: regulation of sleep and wakefulness - medulla, thalamus and basal forebrain : control of sleep and various neurotransmitters 3.6 Doing Without: Sleep Deprivation - 2 types: Partial deprivation (sleep restriction) and selective deprivation 3.6.A Sleep Restriction - when people is okay with getting less sleep than the usual amount - study: the effect depends on the amount of sleeping period deprived and the nature of the job - deprived subjects rate their performance higher than those who get enough sleep - results: sleep deprived people are bad at predicting - sleep is important for our emotional well being 3.6.B Selective Deprivation - subjects are awakened when they fall into REM or NREM stages - Deprived REM: shift sleeping patterns as they tend to shift into REM more frequently -- experience rebound effect: they try to make up for the loss - Deprived of slow wave sleep (during stage 3 and 4): - Importance of getting enough REM and SWS: firming up the learning process, each promotes different types of memory -- sleep enhances subject’s memory of specific learning activities -- foster creative insights - REM sleeps fosters neurogenesis (the generation of new neuron) which facilitates learning - Hippocampus facilitates formation of memories 3.6.C Sleep Loss and Health - sleep restriction triggers hormonal changes that increase hunger - short sleep duration with increased obesity - impaired immune system functioning - but: the studies largely depend on self-report for which the result may be distorted 3.7 Problems in the Night: Sleep Disorders 3.7.A Insomnia - Mean: chronic problems in getting adequate sleep -3 patterns: difficult to fall asleep, difficulty in remaining asleep and persistent early-morning awakening Prevalence - the study on this is rather inaccurate as it totally depends on respondents’ subjective judgments - nearly everyone has sleep difficulty problem (stress, disturbed circa rhythm) - pseudo-insomnia: they underestimate their total duration when it is actually enough Causes - many, like anxiety, tension that keep them awake - study: some people just have higher physiological arousal - Hyperarousal model of insomnia suggests that some people exhibit hormonal patterns associated with arousal Treatment - 2 types: benzodiazepine and nonbenzodiazepine - Benzodiazepine ( Dalmane, Halcion, Restoril) : to relieve anxiety - Nonbezodiazepine (Ambien, Sonarata Lunesta): designed for sleep problems - poor long term solutions, overdose with alcohol and opiate drugs, less effective with frequent intake, will increase insomnia problem - can be overcame with: relaxation procedure and behavioral interventions -- cognitive behavioural therapy (CBT) 3.7.B Other Sleep Problems - there are 6: - Narcolepsy: sudden irresistible onset of sleep during normal waking periods -- suddenly fall into REM state while doing daily routine (10-20 mins) - Sleep apnea: frequent, gasping for air while sleeping -- people stop breathing for a minimum of 10 sec -- heart failure problem - nightmares: anxiety-arousing dreams that lead to awakening during REM stage -- victim cant recall but may remember one frightening image -- associate with neuroticism, trait anxiety, state anxiety and depression - Night terrors (sleep terrors) : abrupt awakening from NREM sleep accompanied by intense autonomic arousal and feelings of panic - remarkable heart acceleration which occurs during stage 4 - Somnambulism: sleepwalking occurs when a person arises and wanders around while remaining asleep, REM stage - REM sleep behavior disorder (RBD): troublesome dream enactment during REM period -- yell, gesture