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Consciousness and Its Variations

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1 Consciousness and Its Variations
McNeely PSYC2301

2 Consciousness Described as a stream or river by William James
Introspection tried to capture the structure of consciousness Modern study includes roles of psychological, physiological, social, and cultural influences McNeely PSYC2301

3 Circadian Rhythm Any rhythmic change that continues at close to a 24-hour cycle in the absence of 24-hour cues body temperature cortisol secretion sleep and wakefulness In the absence of time cues, the cycle period will become somewhat longer than 24 hours Keywords: circadian rhythm McNeely PSYC2301

4 Circadian Rhythm McNeely PSYC2301

5 The Body’s Clock Suprachiasmatic nucleus (SCN)—cluster of neurons in the hypothalamus that governs the timing of circadian rhythms Melatonin—hormone of the pineal gland that produces sleepiness Bright light decreases production of melatonin; decreased light increases melatonin McNeely PSYC2301

6 Stages of Sleep

7 EEG Waves ~jmp/dreams.html McNeely PSYC2301

8 Sleep Changes Throughout Life
Changes in quality and quantity are apparent McNeely PSYC2301

9 Functions of Sleep Restoration theory—body wears out during the day and sleep is necessary to put it back in shape Adaptive theory—sleep emerged in evolution to preserve energy and protect during the time of day when there is considerable danger Keywords: restoration theory, preservation and protection theory McNeely PSYC2301

10 Sleep Deprivation Microsleep--episodes lasting only a few seconds
REM rebound--deprivation of REM sleep causes increase in time spent in REM sleep to “catch up” NREM rebound--catching up on Stages 3 and 4 sleep Keywords: sleep deprivation McNeely PSYC2301

11 Individual Differences in Sleep Drive
Nonsomniacs—sleep far less than most, but do not feel tired during the day Some individuals need more and some less than the typical 8 hours per night Insomniacs—have a normal desire for sleep, but are unable to and feel tired during the day Keywords: nonsomniacs, insomniacs McNeely PSYC2301

12 Sleep Disorders Insomnia—inability to fall asleep or stay asleep
Night terrors—sudden arousal from sleep and intense fear accompanied by physiological reactions (e.g., rapid heart rate, perspiration) that occur during slow-wave sleep Narcolepsy—overpowering urge to fall asleep that may occur while talking or standing up Restless Legs Syndrome--RLS unpleasant sensations in lower legs and urge to move legs disrupts sleep. Sleep apnea—failure to breathe when asleep REM sleep behavior disorder—sleeper acts out his or her dreams Keywords: somnambulism, nightmares, night terrors, narcolepsy, sleep apnea McNeely PSYC2301

13 Dreams and REM Sleep True dream—vivid, detailed dreams consisting of sensory and motor sensations experienced during REM Sleep thinking—lacks vivid sensory and motor sensations, is more similar to daytime thinking, and occurs during slow-wave sleep Keywords: true dream, sleep thought McNeely PSYC2301

14 Brain and REM Sleep Active areas during REM--amygdala and hippocampus
Inactive areas during REM--frontal lobes and primary visual cortex REM sleep plays a role in memory consolidation McNeely PSYC2301

15 Significance of Dreams
Psychoanalytic Interpretation Activation Synthesis Model Keywords: side effect view of dreaming McNeely PSYC2301

16 Psychoanalytic Interpretation
Manifest content—elements of the dream that are consciously experienced and remembered Latent content—the unconscious wishes that are concealed in the manifest content Dreams as “wish fulfillments” McNeely PSYC2301

17 Activation Synthesis Model
Brain activity during sleep produces dream images (activation) which are combined by the brain into a dream story (synthesis). Meaning is to be found by analyzing the way the dreamer makes sense of the progression of chaotic dream images. McNeely PSYC2301

18 Highly focused attention Increased responsiveness to suggestion
Hypnosis State of awareness Highly focused attention Increased responsiveness to suggestion Vivid imagery Willingness to accept distortions of logic Alteration of sensation and perception McNeely PSYC2301

19 Hypnosis and Memory Posthypnotic suggestion--during hypnosis a suggestion is made for the person to carry out some behavior after hypnosis is over Posthypnotic amnesia--inability to remember specific information because of a posthypnotic suggestion Hypermnesia--enhancement of memory because of posthypnotic suggestion McNeely PSYC2301

20 Meditation Sustained concentration that focuses attention and heightens awareness Lowered physiological arousal decreased heart rate decreased BP Predominance of alpha brain waves McNeely PSYC2301

21 Meditation Techniques
Concentration techniques--control attention by focusing awareness on a visual image, word, or phrase Opening-up techniques--control attention by focusing on the “here and now” McNeely PSYC2301

22 Psychoactive Drugs Depressants—inhibit brain activity
Opiates—produce pain relief and euphoria Stimulants—increase brain activity Psychedelics—distort sensory perceptions McNeely PSYC2301

23 Common Properties Physical dependence Tolerance Withdrawal symptoms
Drug rebound effect McNeely PSYC2301

24 Depressants Alcohol—CNS depressant
Barbiturates—induce sleep but can cause dependence and as a result serious withdrawal symptoms Tranquilizers—relieve anxiety but can be addictive Effects are additive McNeely PSYC2301

25 BAC Effects Euphoria (BAC = 0.03 to 0.12)
Excitement (BAC = 0.09 to 0.25) Confusion (BAC = 0.18 to 0.30) Stupor (BAC = 0.25 to 0.4) Death (BAC more than 0.50 ) They become more self-confident or daring. Their attention span shortens. They may look flushed. Their judgment is not as good - they may say the first thought that comes to mind, rather than an appropriate comment for the given situation. They have trouble with fine movements, such as writing or signing their name. McNeely PSYC2301

26 Areas of the brain that may be affected by FAS
The illustration below is from Vol. 18, No. 1, 1994 of the Journal Alcohol Health & Research World. From website: Areas of the brain that may be affected by FAS McNeely PSYC2301

27 Opiates Chemically similar to morphine and have strong pain-relieving properties, can be addictive Mimic the brain’s endorphins Heroin, methadone Percodan, Demerol McNeely PSYC2301

28 Stimulants Caffeine Nicotine Amphetamines Cocaine
Stimulant induced psychosis McNeely PSYC2301

29 Psychedelics Create perceptual distortions Mescaline LSD Marijuana
Flashback reactions and psychotic episodes McNeely PSYC2301

30 “Club” Drugs Ecstasy (MDMA)—feelings of euphoria, increased well-being
Side effects—dehydration, hyperthermia, tremor, rapid heartbeat Dissociative anesthetics—include PCP and Ketamine. Deaden pain, produce stupor or coma, and may induce hallucinations. McNeely PSYC2301

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