Modules 7 - 9 Consciousness

Consciousness Awareness of ourselves and our environment: Subjective: own conscious experiences Selective attention: ability to focus awareness on a single stimulus Divided attention: different stimuli at the same time. Stream of consciousness: flow of thoughts, feelings, and sensations Many levels of consciousness

Circadian Rhythms The behavioral cycle of sleep and wakefulness that we naturally follow throughout our lives Circadian rhythms correspond to physiological changes, such as body temperature, blood pressure, and hormone levels.

LO 4.2 Why Sleep and How Sleep Works Circadian Rhythm LO 4.2 Why Sleep and How Sleep Works : a cycle of bodily rhythm that occurs over a twenty-four-hour period “circa”: about “diem”: day

Circadian Rhythms Jet lag The severity of this jet lag depends on whether you fly westward or eastward. When flying westward your regular sleep cycle is pushed back five hours (a phase delay). The jet lag resulting from such east-west travel is easier to adjust to—and thus, less severe—than eastward-induced jet lag. When flying eastward your day is being shortened (a phase advance), which is not only farther away from your natural 24-hour sleep-wake cycle but also is inconsistent with people’s day-stretching habits.

Circadian Rhythms Sleep-wakefulness cycles A small area of the hypothalamus known as the suprachiasmatic nucleus and the hormone melatonin, produced by the pineal gland, appear to be crucial in readjusting the body’s sleep-wake cycle.

Sleep A nonwaking state of consciousness characterized by minimal physical movement and responsiveness to one’s surroundings.

Why We Sleep Why do we sleep? Body needs sleep and will malfunction without a sufficient amount Restorative theory: Sleep allows the body to restore itself following the rigors of daily activity. Safety/conservation theory: It prevents us from moving about and being injured. It conserves energy. We honestly don’t know why we sleep.

LO 4.2 Why Sleep and How Sleep Works Necessity of Sleep LO 4.2 Why Sleep and How Sleep Works Hypothalamus: tiny section of the brain that influences the glandular system suprachiasmatic nucleus: deep within the hypothalamus; the internal clock that tells people when to wake up and when to fall asleep The hypothalamus tells the pineal gland to secrete melatonin, which makes a person feel sleepy.

Sleep Deprivation Effects of Sleep Loss fatigue impaired concentration immune suppression irritability slowed performance accidents planes autos and trucks

Sleep Deprivation Accident frequency Spring time change 2,400 2,700 2,600 2,500 2,800 Spring time change (hour sleep loss) 3,600 4,200 4000 3,800 Fall time change (hour sleep gained) Less sleep, more accidents More sleep, fewer accidents Monday before time change Monday after time change Accident frequency

Sleep Habits Vary by Age Newborns sleep about 16 hours Children average between 9 and 12 hours Adolescents average about 7.5 hours. Newborns and young children have the highest percentage of REM sleep. Many sleep experts believe that the heightened brain activity during REM sleep in the young promotes the development of new neural pathways.

Sleep Habits Vary by Age In adulthood, both quantity & quality of sleep decrease with age. Less time is spent in slow-wave sleep. There is more stage 1 sleep and more awakenings during the night. The percentage of REM sleep only diminishes in later life.

Sleep Patterns of Infants and Adults

Sleep Habits Vary Individually Morning people (25%) wake up early, with a good deal of energy and alertness, but are ready to retire before 10:00 p.m. Night people (25%) stay up much later and have a hard time getting up early in the morning. This different sleep pattern appears to be related to differences in circadian body temperatures. Morning persons’ body temperatures rise quickly rise upon awakening. The body temperature of night persons rises gradually and peaks later.

Sleep Habits Vary Culturally People in industrialized settings sleep less. This may have to do with work. Electricity also extends the time people can be active and productive.

Stages of Sleep Stage:1 hypnogogic state: transition between wakefulness and sleep myoclonic jerk; hypnogogic hallucinations Stage 2: lasts about 20 minutes and is characterized by sleep spindles Stage 3: slow-wave sleep; brain waves higher in amplitude and slower in frequency Stage 4: delta waves much more pronounced REM (rapid eye movement) sleep: “Active sleep” completes the sleep cycle.

LO 4.2 Why Sleep and How Sleep Works Brain Wave Patterns Electroencephalograph (EEG) allows scientists to see the brain wave activity as a person passes through the various stages of sleep and to determine what type of sleep the person has entered alpha waves: brain waves that indicate a state of relaxation or light sleep theta waves: brain waves indicating the early stages of sleep delta waves: long, slow waves that indicate the deepest stage of sleep LO 4.2 Why Sleep and How Sleep Works

Sleep

LO 4.3 Stages of Sleep and Dreaming Non-REM stage 1: light sleep may experience: hypnagogic images: vivid visual events hypnic jerk: knees, legs, or whole body jerks Non-REM stage 2: sleep spindles (brief bursts of activity only lasting a second or two) LO 4.3 Stages of Sleep and Dreaming

LO 4.3 Stages of Sleep and Dreaming Non-REM stages 3 and 4: delta waves pronounced deep sleep: when 50 percent or more of waves are delta waves.

Stages of Sleep Stage:1 hypnogogic state: transition between wakefulness and sleep myoclonic jerk; hypnogogic hallucinations Stage 2: lasts about 20 minutes and is characterized by sleep spindles Stage 3: slow-wave sleep; brain waves higher in amplitude and slower in frequency Stage 4: delta waves much more pronounced REM (rapid eye movement) sleep: “Active sleep” completes the sleep cycle.

First Cycle (90 Minutes) of Sleep

LO 4.3 Stages of Sleep and Dreaming Rapid eye movement (REM): stage of sleep in which the eyes move rapidly under the eyelids and the person is typically experiencing a dream NREM (non-REM) sleep: any of the stages of sleep that do not include REM LO 4.3 Stages of Sleep and Dreaming

REM Sleep REM phase of sleep is paradoxical. People dream during REM. Brain waves are active. Body is paralyzed. People dream during REM. Eugene Aserinsky discovered the association between rapid eye movement and dreaming. 78 % of people awakened from REM sleep report dreaming.

Importance of REM Sleep Participants deprived of REM sleep often report feeling more tired. They may experience dreamlike images during the day They spend extra time REM sleep following deprivation. This is called REM rebound.

LO 4.3 Stages of Sleep and Dreaming REM Sleep and Dreaming LO 4.3 Stages of Sleep and Dreaming REM sleep is paradoxical sleep (high level of brain activity). If wakened during REM sleep, sleepers almost always report a dream. REM rebound: increased amounts of REM sleep after being deprived of REM sleep on earlier nights

Theories of Dreams Biological Dream Theories Dreams as interpreted brain activity Dreaming is simply a by-product of brain activity. Activation-synthesis theory A dream is the forebrain’s attempt to interpret the random neural activity initiated in the midbrain during sleep. There is no consensus on the cause or meaning of dreams.

Theories of Dreams Psychological Dream Theories Dreams as wish fulfillment (Freud) Dreams are disguised wishes originating in the unconscious mind. Dreams as problem solving (emotions) Dreams provide people with the opportunity to creatively solve their everyday problems. Dreams as information processing (memory) Off-line dream theory contends that the cognitive processing that occurs during dreaming consolidates and stores information gathered during the day.

LO 4.10 What Are Hypnogogic and Hypnopompic Hallucinations? Hypnogogic Hallucination: a type of hallucination that can occur just as a person is entering Stage 1 sleep Hypnopompic Hallucination: a hallucination that happens just as a person is in the between-state of being in REM sleep (in which the voluntary muscles are paralyzed) and not yet fully awake LO 4.10 What Are Hypnogogic and Hypnopompic Hallucinations?

LO 4.4 Sleep Disorders and Normal Sleep Problems during Sleep LO 4.4 Sleep Disorders and Normal Sleep Insomnia: the inability to get to sleep, stay asleep, or get a good quality of sleep Sleep apnea: disorder in which the person stops breathing for nearly half a minute or more CPAP: continuous positive airway pressure device

Sleep Disorders Insomnia Narcolepsy recurring problems in falling or staying asleep Narcolepsy uncontrollable sleep attacks sufferer may lapse directly into REM sleep, often at inopportune times

Stage Four Sleep Disorders LO 4.4 Sleep Disorders and Normal Sleep Sleepwalking (Somnambulism) Occurring during deep sleep, sleepwalking is an episode of moving around or walking around in one’s sleep. Sleepwalking is more common among children than adults. Sleeptalking

Stage Four Sleep Disorders LO 4.4 Sleep Disorders and Normal Sleep Night terrors relatively rare disorder in which the person experiences extreme fear and screams or runs around during deep sleep without waking fully

LO 4.4 Sleep Disorders and Normal Sleep Nightmares bad dreams occurring during REM sleep REM Behavior Disorder a rare disorder in which the mechanism that blocks the movement of the voluntary muscles fails, allowing the person to thrash around and even get up and act out nightmares

Problems Related to REM Sleep LO 4.4 Sleep Disorders and Normal Sleep Narcolepsy: sleep disorder in which a person falls immediately into REM sleep during the day without warning cataplexy: sudden loss of muscle tone

Psychoactive Drugs

LO 4.7 Physical and Psychological Dependence on a Drug Psychoactive Drugs Psychoactive drugs: drugs that alter thinking, perception, and memory Physical Dependence tolerance: more and more of the drug is needed to achieve the same effect withdrawal: physical symptoms that can include nausea, pain, tremors, crankiness, and high blood pressure, resulting from a lack of an addictive drug in the body systems LO 4.7 Physical and Psychological Dependence on a Drug

LO 4.7 Physical and Psychological Dependence on a Drug Psychoactive Drugs Psychological dependence: the feeling that a drug is needed to continue a feeling of emotional or psychological well-being LO 4.7 Physical and Psychological Dependence on a Drug

LO 4.8 How Do Stimulants and Depressants Affect Consciousness? Stimulants: drugs that increase the functioning of the nervous system amphetamines: drugs that are synthesized (made in labs) rather than found in nature cocaine: natural drug; produces euphoria, energy, power, and pleasure nicotine: active ingredient in tobacco LO 4.8 How Do Stimulants and Depressants Affect Consciousness?

LO 4.8 How Do Stimulants and Depressants Affect Consciousness? Stimulants: drugs that increase the functioning of the nervous system caffeine: the stimulant found in coffee, tea, most sodas, chocolate, and even many over-the-counter drugs LO 4.8 How Do Stimulants and Depressants Affect Consciousness?

LO 4.8 How Do Stimulants and Depressants Affect Consciousness? Depressants: drugs that decrease the functioning of the nervous system barbiturates: depressant drugs that have a sedative effect benzodiazepines: drugs that lower anxiety and reduce stress Rohypnol: the “date rape” drug LO 4.8 How Do Stimulants and Depressants Affect Consciousness?

LO 4.8 How Do Stimulants and Depressants Affect Consciousness? Alcohol Alcohol: the chemical resulting from fermentation or distillation of various kinds of vegetable matter Often taken for a stimulant, alcohol is actually a depressant on the CNS. LO 4.8 How Do Stimulants and Depressants Affect Consciousness?

Table 4.5 (continued) Blood Alcohol Level and Behavior Associated With Amounts of Alcohol

LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana A class of opium-related drugs, narcotics suppress the sensation of pain by binding to and stimulating the nervous system’s natural receptor sites for endorphins. opium: substance derived from the opium poppy from which all narcotic drugs are derived morphine: narcotic drug derived from opium; used to treat severe pain heroin: narcotic drug derived from opium that is extremely addictive LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana

LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana Psychogenic Drugs drugs including hallucinogens and marijuana that produce hallucinations or increased feelings of relaxation and intoxication hallucinogens: drugs that cause false sensory messages, altering the perception of reality LSD (lysergic acid diethylamide): powerful synthetic hallucinogen PCP: synthesized drug now used as an animal tranquilizer that can cause stimulant, depressant, narcotic, or hallucinogenic effects LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana

LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana Psychogenic Drugs (cont’d) MDMA (Ecstasy or X): designer drug that can have both stimulant and hallucinatory effects Stimulatory hallucinogenics: drugs that produce a mixture of psychomotor stimulant and hallucinogenic effects Mescaline: natural hallucinogen derived from peyote cactus buttons LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana

LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana Psychogenic Drugs (cont’d) psilocybin: natural hallucinogen found in certain mushrooms LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana

LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana Marijuana (pot or weed): mild hallucinogen derived from the leaves and flowers of a particular type of hemp plant This woman is preparing a cannabis (marijuana) cigarette. Cannabis is reported to relieve pain in cases of multiple sclerosis and chronic pain from nerve damage. Such use is controversial as cannabis is classified as an illegal drug in some countries. LO 4.9 Dangers of Narcotics, Hallucinogens, and Marijuana