Presentation on theme: "States of Consciousness. I. Sleep A. Circadian Rhythms: cycles of activity and inactivity generally lasting about one day. B. Shifting Sleep Schedules."— Presentation transcript:
I. Sleep A. Circadian Rhythms: cycles of activity and inactivity generally lasting about one day. B. Shifting Sleep Schedules 1) Jet Lag: the period of weariness and discomfort that occurs while your body clock is out of step with your new time zone. 3) Suprachiasmic Nucleus (SCN): tiny structure in the brain that governs the circadian cycle of sleep and wakeful states. The SCN controls the sleep-wake cycle in part by regulating the secretion of the hormone melatonin by the pineal gland. 2) Staying up late and shifting work schedules…
C. Why Do We Sleep? 1) Repair and Restoration Theory of Sleep: the reason that we sleep is to allow the body time to recover from the exertions of the day. 2) Energy Conservation Theory (Evolutionary Theory): evolution has equipped all animals with a regular pattern of sleep and wakefulness to help us conserve energy and avoid dangers. D. Stages of Sleep 1) Rapid-Eye Movement (REM): the sleeper’s eyes are moving rapidly around under the closed eyelids.
2) Non-REM (NREM) Stages of Sleep Stage 1: there is little eye movement, and a fair amount of brain activity. Stage 2: a gradual transition to slow brain wave deep sleep. Stages 3 and 4: stages of even deeper sleep. You gradually move back through stages 3 and 2 and then have your first brief REM episode of the night. (REM replaces stage 1 and then the cycle of stages repeats). A healthy adult has several 90-100 minute sleep cycles during the night. The last sleep cycles of the night are usually comprised of alternations between stage 2 and REM.
II. Dreaming A. Adults awakened during REM sleep report dreams 85-90% of the time. B. Adults awakened during NREM sleep report dreams 50-60% of the time. C. Children less than 5 years old rarely report any dreams. D. Dreams appear to follow REM in length; 1 minute of REM produces a brief dream, longer periods are associated with more complex dream stories.
F. Infants get more REM sleep than children, and children get more than adults. E. When people are deprived of only REM sleep (experimenters will monitor sleepers and then wake them up only during REM sleep), their brains will engage in more and more of it on subsequent nights. They will also become quite irritable, anxious and distracted.
2) Activation-Synthesis Theory of Dreams: input from the brainstem activates the brain during REM sleep. The cerebral cortex tries to make sense of the random activity by imposing a story on the stimuli that activate the sense organs during this process. Manifest Content: the surface content of the dream. Latent Content: the hidden content, represented only in symbols. According to Freud, the meaning of the latent content can only be determined via the dreamer’s associations to the details of the manifest content. G. Theories of Dreaming 1) Freud’s Theory…
H. Lucid Dreaming: a dream state in which one is conscious enough to recognize that one is in the dream state. 3) Neurocognitive Theory: the stronger the imagination of the person when awake, the greater the chance of dreaming.
III. Abnormalities of Sleep A. Insomnia: lack of sleep. B. Sleep Apnea: the person may fail to breathe for a minute or longer and wake up gasping for breath. C. Narcolepsy: sudden attacks of extreme and irresistible sleepiness during the day. D. Sleep Talking: is not a symptom of any mental or emotional disorder. E. Sleep Walking: is usually found in children.
F. Sleep Hallucinations: an individual opens their eyes during sleep and will see people or objects that aren’t physically present. G. Sleep Terrors: involve waking up during slow-wave sleep in an extreme panic. H. Restless Leg Syndrome: prolonged “crawly” sensations in the legs, accompanied by strong repetitive leg movements that can wake the sleeper. I. Hypersomnia: excessive sleep that is unrefreshing.
IV. Hypnosis: a condition of increased suggestibility that occurs in the context of a special hypnotist-subject relationship. A. How do you induce hypnosis? B. Uses and limitations of hypnosis… 4) It will NOT give a person new mental or physical abilities, like enhancing memory or lifting up automobiles. 1) Increased relaxation. 2) Better concentration. 3) Temporary changes in behavior that sometimes persist beyond the end of the hypnotic state.
C. Posthypnotic Suggestion: a suggestion to do or experience something particular after coming out of hypnosis. D. Distortions of perception can occur under hypnosis. E. Is hypnosis an altered state of consciousness? F. Meditation: a method of inducing a calm, relaxed state through the use of special techniques.
V. Drugs: operate at the synaptic level. They can increase the release of neurotransmitters, block reuptake, or directly stimulate or block receptors. A. Stimulants: drugs that boost energy, heighten alertness, increase activity and produce a pleasant feeling. B. Depressants: drugs that largely decrease physiological arousal. 1)Alcohol: a class of chemicals including methanol, ethanol, and propyl (rubbing) alcohol. 2) Tranquilizers: make people relax and possibly fall asleep.
C. Narcotics: drugs that produce drowsiness, insensitivity to pain, and overall decreased responsiveness to environmental Stimuli (ex. morphine, heroin). 1) Opiates: can be derived naturally from the opium poppy or synthesized in the laboratory. E. Marijuana: intensifies sensory experiences and has a calming effect or sometimes an arousing effect. D. Hallucinogens: drugs that induce sensory distortions and false sensory experiences. 1) Peyote: a naturally derived hallucinogen. 2) LSD: a hallucinogen that is artificially manufactured. 3) Ecstasy: acts as a stimulant at low doses and a hallucinogen at high doses.
VI. Chronic Drug Effects A. Withdrawal: an unpleasant effect, the opposite of how a drug made the user feel initially. B. Tolerance: a decrease in effect develops as the user continues to take the drug. C. Physical Dependence: when the user feels compelled to use a drug chiefly to reduce the unpleasant withdrawal symptoms. D. Psychological Dependence: a craving to use a drug not motivated by the physical symptoms of withdrawal.