Consciousness and Its Variations

1. Consciousness and Its Variations

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

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

4. Circadian Rhythm

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

6. Stages of Sleep

7. EEG Waves ist-socrates.berkeley.edu/ ~jmp/dreams.html

8. Sleep Changes Throughout Life • Changes in quality and quantity are apparent

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

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

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

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

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

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

15. Significance of Dreams • Psychoanalytic Interpretation • Activation Synthesis Model

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”

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.

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

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

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

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”

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

23. Common Properties • Physical dependence • Tolerance • Withdrawal symptoms • Drug rebound effect

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

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 )

26. Areas of the brain that may be affected by FAS

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

28. Stimulants • Caffeine • Nicotine • Amphetamines • Cocaine • Stimulant induced psychosis

29. Psychedelics • Create perceptual distortions • Mescaline • LSD • Marijuana • Flashback reactions and psychotic episodes

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.