Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Chapter 5: States of Consciousness Nathan Jacquez Sleep Circadian rhythm. The biological clock. The suprachiasmatic nucleus (SCN) is in the hypothalamus and increases or decreases the secretion of melatonin from the pineal gland. Light also affects the circadian rhythm and secretion of melatonin. Sleep Stages Nathaniel Kleitman and Aserinsky used an EEG to discover the stages of sleep. Being aware produces alpha waves. Stage One sleep shows theta waves. Stage Two shows sleep spindles (bursts of activity). Stages Three and four show delta waves. REM sleep (paradoxical sleep) occurs after each stage is complete. Sleep Loss Causes fatigue and impairs concentration, creativity, and communication. Leads to obesity, hypertension, a suppressed immune system, irritability, and slowed performance. Sleep deprivation increases ghrelin and decreases leptin. Increases cortisol, which increases stress and stimulates the body to make fat. Functions of Sleep Protection: our ancestors lived longer when not traveling at night and instead sleeping in a cave. Recuperation: repairs brain tissue and lessens the production of free radicals. Making memories: restores and rebuilds our fading memories. Creative thinking: sleep boost to learning and thinking. Growing: pituitary gland releases a growth hormone during sleep. Sleep Disorders Insomnia: recurring problems in staying or falling asleep. How to prevent it: Exercise regularly (late afternoon is the best) Avoid caffeine Relax before bedtime Sleep schedule Manage stress levels Go to bed earlier or later Sleep Disorders Narcolepsy: uncontrollable sleep attacks. Attacks usually last five minutes but often occur at inopportune times. People with severe cases may drop directly into REM sleep. Occurs 1 in every 2000 of us. Why does it happen? Absence of orexin which is linked to alertness. It is a brain disease, not “in your mind.” Sleep Disorders Sleep apnea: temporary cessation or breathing during sleep and repeated momentary awakenings. Associated with obesity. Night terrors: high arousal and an appearance of being terrified during sleep. Occurs during stage 4 sleep, as well as sleepwalking, within two or three hours of falling asleep. Not usually remembered. Dreams Five major views of the functions of dreams: 1. Freudian: safety valve, manifest content, and latent content. 2. Information-processing: sort out the day and fix them in memories. 3. Brain stimulation: preserve neural pathways in the brain. 4. Activation-synthesis: make sense of neural static. 5. Brain-maturation/cognitive-development: represent levels of development, knowledge, and understanding. Occurs during REM sleep. REM rebound. Hypnosis Social interaction in which one person suggests to another the certain perceptions, feelings, thoughts, or behaviors will spontaneously occur. Does not enhance the recall of forgotten events. Can help relieve pain. Posthypnotic suggestions have helped people harness their own healing powers. Mind over body. Some psychologists say hypnosis is dissociation, which is a split between normal sensations and conscious awareness. Others say it is just a social phenomenon due to social influence. Some even say there is a unified approach. Combining social influence and dissociation. Drugs and Consciousness Psychoactive drugs are chemicals that alter perceptions and moods. Tolerance is the diminishing effect with regular use of the same dose of a drug, requiring the user to take larger doses before experiencing the drug’s effect. Withdrawal is the discomfort and distress that follow discontinuing the drug’s effect. Physical dependence is a physiological need for a drug. Psychological dependence is a psychological need for a drug. Addiction is a compulsive craving for a substance despite adverse consequences. Depressants Drugs that reduce neural activity and slow body functions. Alcohol Disinhibition Slowed neural processing Memory disruption Reduced self-awareness and self-control Expectancy: if you believe that you have been drinking alcohol, you will act like it. Depressants Barbiturates- tranquilizers Reduces anxiety and impairs memory. Mimic the effects of alcohol. Sometimes used to induce sleep, but can cause death in large doses. Opiates- opium Reduce anxiety and pain. Heroin and narcotics. Short-term pleasure but a long-term price. Brain stops producing endorphins. Stimulants Methamphetamines excite neural activity and speed up body functions May cause permanently depressed dopamine level functioning. Caffeine is the world’s most widely consumed psychoactive substance. Nicotine Cocaine As powerfully and quickly addictive as heroin and cocaine. Releases epinephrine and norepinephrine. Enters bloodstream quickly resulting in euphoria. Blocks reuptake of dopamine, norepinephrine, and serotonin. Ecstasy or MDMA A stimulant and a mild hallucinogen. Triggers dopamine release and blocks reabsorption of serotonin. Can lead to severe overheating, increased blood pressure, and death. Can damage serotonin-producing neurons. Suppresses immune system, impairs memory, and disrupts sleep. Hallucinogens Psychedelic drugs that distort perceptions and evoke sensory images in the absence of sensory input. LSD Near-death experience Discovered by Albert Hoffmann Extremely hallucinogenic Similar to serotonin An altered state of consciousness reported after a close brush with death. Similar to drug-induced hallucinations. Marijuana THC triggers a variety of effects, including mild hallucinations. Relaxes, disinhibits, and may produce a euphoric high. Impairs motor coordination, perceptual skills, and reaction time. Influences on Drug Use Biological Influences Psychological Influences More susceptible to alcohol dependence if one or both biological parents have a history of it. Identical twin has alcohol dependence. Some genes do predispose people to alcohol dependence. Feeling that one’s life is meaningless. Significant stress. Social-Cultural Influences Peers/friends