psy i ch.4

Copyright © Allyn & Bacon 2006

States of Consciousness

Chapter Four

This multimedia product and its contents are protected under copyright law. The following are prohibited by law:

• Any public performance or display, including transmission of any image over a network;

• Preparation of any derivative work, including the extraction, in whole or in part, of any images;

• Any rental, lease, or lending of the program.Slide author:

Cynthia K. Shinabarger Reed

Book authors:

Samuel Wood

Ellen G. Wood

Denise Boyd


Chapter Four Overview

What is Consciousness? Circadian Rhythms

The Influence of Circadian Rhythms The Suprachiasmatic Nucleus Jet Lag Shift Work Circadian Rhythm Timing and Neurological

Disorders



Sleep NREM and REM Sleep Sleep Cycles Variations in Sleep Explaining the Function of Sleep Sleep Deprivation Dreams Interpreting Dreams Sleep Disorders



Meditation and Hypnosis Meditation Hypnosis Theories of Hypnosis

Culture and Altered States of Consciousness



Psychoactive Drugs How Drugs Affect the Brain Reasons for Substance Abuse Drug Addiction The Behavioral Effects of Psychoactive

Drugs Herbal Remedies and Supplements


What is Consciousness?

• Consciousness

– Everything of which we are aware at any given time including our thoughts, feelings, sensations, and perceptions of the external environment.

– William James likened consciousness to a flowing stream that sometimes is influenced by the will and sometimes is not.



• Consciousness (continued)

– Sigmund Freud emphasized the notion that unconscious wishes, thoughts, and feelings are hidden from consciousness because they evoke too much anxiety.

– John Watson urged psychologists to abandon the study of consciousness, claiming that it could not be studied scientifically.



• Altered states of consciousness

– Changes in awareness produced by sleep, meditation, hypnosis, and drugs

– Modern brain-imaging techniques have allowed psychologists to accumulate a large body of evidence leading to a better understanding of the neurological basis of consciousness


Circadian Rhythms• Influence of circadian rhythms

– Within each 24-hour period, the regular fluctuation from high to low points of certain bodily functions

– Two circadian rhythms of importance to the study of sleep

• Sleep/wakefulness cycle• Body temperature

– Normal body temperature ranges from a low of about 97 or 97.5 degrees between 3:00 and 4:00 a.m. to a high of about 98.6 degrees between 6:00 and 8:00 p.m.

– People sleep best when their body temperature is lowest


Circadian Rhythms

• Suprachiasmatic nucleus (SCN)– A tiny pair of structures in the brain’s

hypothalamus that controls the timing of circadian rhythms

– The ebb and flow of circadian rhythms is not strictly biological; environmental cues also play a part

• Melatonin– A hormone secreted by the pineal gland

from dusk to shortly before dawn– Induces sleep


Circadian Rhythms• Jet lag

– When traveling, you reach your destination at a time when it is daylight there, but it would have been time to go to sleep at the place you started

– Can produce memory deficits that may be permanent

– Melatonin supplements have been found to be helpful for alleviating jet lag in some long-distance travelers

– For others, exposure to bright sunlight during the early morning hours and avoidance of bright lights during the evening hours may be more effective


Circadian Rhythms• Shift work

– When people work during the night and sleep during the day

– Shift workers average 2 to 4 hours less sleep than nonshift workers of the same age

– Subjective night• The time during a 24-hour period when body

temperature is lowest and when the biological clock is telling a person to go to sleep

• During subjective night, energy and efficiency are at their lowest point, reaction time is slowest, productivity is diminished, and industrial accidents are significantly higher


Circadian Rhythms

• Shift work (continued)– Rotating work schedules forward from days

to evenings to nights makes adjustment easier because people find it easier to go to bed later and wake up later than the reverse

– Shift workers who temporarily reside at their workplaces, such as offshore oil rigs, appear to adjust more easily to the demands of night work than do those who live at home

– Light exposure is another important factor affecting adjustment to shift work


Circadian Rhythms

• Circadian Timing and Neurological Disorders– A number of neurological diseases and

psychiatric disorders are associated with disturbances in circadian functioning

– Abnormal circadian rhythms are common in Alzheimer’s patients

– Individuals with non-Alzheimer’s types of dementia do not exhibit circadian disturbances; this may provide researchers with a simple way of distinguishing between Alzheimer’s and other types of dementia


Sleep• NREM sleep

– Sleep in which there are no rapid eye movements

– Characterized by slow, regular heart rate and respiration

– Blood pressure and brain activity are at a 24-hour low point

– Has four stages, with Stage 1 being the lightest sleep and Stage 4 being the deepest

– Each stage can be identified by its brain-wave pattern


Brain-Wave Patterns Associated with Different Stages of Sleep



Sleep

• REM sleep– Sleep characterized by rapid eye

movements, paralysis of large muscles, fast and irregular heart rate and respiration rate, increased brain-wave activity, and vivid dreams

– Sometimes called “active sleep”– REM sleep behavior disorder

• Individuals are not paralyzed during REM sleep

• They often act out their dreams


Sleep

• REM sleep (continued)

– Eugene Aserinsky

• Discovered the bursts of rapid eye movements when in the REM state

– William Dement and Nathaniel Kleitman

• Made the connection between rapid eye movements and dreaming


Sleep

• Nocturnal erection– Regardless of the content of dreams, males

have a full or partial erection during REM sleep, and females experience vaginal swelling and lubrication

– In males suffering from impotence, the presence of an erection during REM sleep, even occasionally, indicates that the impotence is psychological; the consistent absence of an erection indicates that the impotence may be physiological in origin


Sleep• Function of REM sleep

– Researchers say that REM sleep aids in information processing, helping people sift through daily experience, to organize and store in memory information that is relevant to them

– Researchers have found that sleep may be critical to the consolidation of memories after learning

– Francis Crick and Graeme Mitchison suggest that REM sleep functions as mental housecleaning, erasing trivial and unnecessary memories and clearing overloaded neural circuits that might interfere with memory and rational thinking


Sleep• Function of REM sleep (continued)

– The fact that newborns show a high percentage of REM sleep has led to the conclusion that this type of sleep is necessary for maturation of the brain during infancy.

– When people are deprived of REM sleep they will make up for the deprivation by getting an increased amount of REM sleep afterward, a phenomenon called REM rebound.


Sleep

• Sleep cycles– A cycle of sleep lasting about 90 minutes and

including one or more stages of NREM sleep followed by a period of REM sleep

– Stage 1 sleep is the transition stage between waking and sleeping

– Stage 2 sleep puts a person somewhat more deeply asleep and harder to awaken; sleep spindles appear

– As sleep gradually becomes deeper, brain activity slows, and more delta waves appear in the EEG


Sleep

• Sleep cycles (continued)

– Stage 3 sleep is entered when the EEG registers 20% delta waves; this is the beginning of slow-wave sleep

– When delta waves reach more than 50%, people enter Stage 4 sleep; this is the deepest sleep and the person is hardest to awaken


Sleep• Sleep cycles (continued)

– After the first two sleep cycles of about 90 minutes each, the sleep pattern changes and sleepers usually get no more Stage 4 sleep

– During each additional 90-minute sleep cycle, people alternate mainly between Stage 2 and REM sleep for the remainder of the night

– Most people have about five sleep cycles


Sleep

• Variations in sleep

– There is considerable individual variation in the amount of sleep people need, and, for each individual, a certain amount of sleep may be sufficient at one point in life but insufficient at another


Sleep• Sleep changes over the life span

– In a longitudinal study begun in 1982, more than a million Americans were asked about their sleep habits• Twenty years later, people who reported

sleeping 6 or fewer hours per night, along with those who slept more than 8, were more likely to have died than adults who slept about 7 hours each night


Sleep• Sleep changes over the life span

(continued)

– As people age, the quality and quantity of sleep usually decrease

– Older adults have more difficulty falling asleep than younger people do, and typically sleep more lightly


Sleep

• Larks and owls– Larks

• Awaken early every morning and leap out of bed with enthusiasm, eager to start the day

• Body temperature rises rapidly after they awaken and stays high until about 7:30 p.m.

• Turn in early and have the fewest sleep problems


Sleep

– Owls• Fumble for the alarm clock and push the

snooze button to get a few more precious minutes of sleep

• Body temperature of an owl gradually rises throughout the day, peaking in the afternoon and not dropping until later in the evening


Sleep• Larks and owls (continued)

– Guthrie and others

• Compared the performance of several hundred college students classified as larks or owls

• Found that the larks made better grades in early morning classes, while the owls made higher grades in classes they took later in the day

• A gene that runs the biological clock is responsible, in part, for the differences between larks and owls


Sleep

• Explaining the Function of Sleep– Restorative theory of sleep

• The theory that the function of sleep is to restore body and mind

– Circadian (evolutionary) theory of sleep• The theory that sleep evolved to keep

humans out of harm’s way during the night, possibly from becoming prey for some nocturnal predator


Sleep

• Explaining the function of sleep (continued)– Alexander Borbely believes that

• people feeling sleepy at certain times of day is consistent with the circadian theory

• sleepiness increasing the longer a person is awake is consistent with the restorative theory

• the urge to sleep is partly a function of how long a person has been awake and partly a function of the time of day


Sleep

• Sleep deprivation– Research indicates that even the rather

small amount of sleep deprivation associated with delaying your bedtime on weekends leads to decreases in cognitive performance and increases in negative mood on Monday morning

– After 60 hours without sleep, cognitive performance declines substantially


Sleep

• Sleep deprivation (continued)– Microsleep

• 2- to 3-second lapses from wakefulness into sleep, usually occurring when a person has been sleep-deprived

– A meta-analysis by Pilcher and Huffcutt using data from more than 1,900 subjects indicated that sleep deprivation seriously impairs human functioning


Sleep

• Sleep deprivation (continued)– It negatively impacts mood, alertness, and

performance and reduces the body’s ability to warm itself, even at relatively comfortable temperatures

– Partial sleep loss, even for one night, can significantly reduce the effectiveness of the human immune system


Sleep• Sleep deprivation and the brain

– Sleep deprivation impairs a variety of cognitive functions

– Drummond and others• Used brain-imaging techniques to map the

patterns of brain activity during a verbal learning task in two groups of participants

• Those in an experimental group were deprived of sleep for about 35 hours, while those in a control group had slept normally

• The prefrontal cortex and the temporal lobes were highly active in the control group, but the temporal lobes were almost totally inactive and the prefrontal cortex even more active in the sleep-deprived group


Sleep

• Dreams

– REM dreams

• The vivid dreams people remember and talk about are usually REM dreams

• Have a story-like quality

• occurring almost continuously during each REM period; more vivid, visual, and emotional than NREM dreams


Sleep

• Dreams (continued)

– NREM dreams

• Mental activity occurring during NREM sleep that is more thought-like in quality than REM dreams are

• Less frequent and less memorable than REM dreams


Sleep

• Content of dreams

– Griffith and others

• Asked 250 college students about the themes of their dreams

• Most common themes: 70% or more of the sample reported falling, being attacked or chased, trying repeatedly to do something, and studying


Sleep

• REM sleep, dreaming, and the brain

– Brain-imaging studies suggest that our general perception that events in REM dreams are stranger and more emotion-provoking than our waking experiences is probably true

– The emotional areas of the brain, as well as the primary visual cortex, are active during REM dreams


Sleep• REM sleep, dreaming, and the brain

(continued)– The prefrontal cortex is suppressed,

suggesting that the bizarre events that happen in dreams result from the inability of the brain to structure perceptions logically during REM sleep

– Areas associated with memory are also suppressed

– Different neurotransmitters are dominant in the cortex during wakefulness and during REM sleep


Sleep

• REM sleep, dreaming, and the brain (continued)– When we are awake, powerful inhibiting

influences exert control over the functioning of the cortex, keeping us anchored to reality, less subject to impulsive thoughts and acts, and more or less “sane”

– These inhibiting influences are maintained principally by cortical neurons that are responding to serotonin and noradrenalin


Sleep• REM sleep, dreaming, and the brain

(continued)

– Mark Solms

• Believes that there is mounting evidence that dreaming and REM sleep, while normally occurring together, are not one and the same

• Instead, the REM state is controlled by neural mechanisms in the brainstem, while areas in the forebrain provide the neural pathway for the complex and often vivid mental experiences we call dreams


Sleep

• REM sleep, dreaming, and the brain (continued)

– Vivid REM dreams are associated with distributions of activity in the forebrain that are very similar to those exhibited by individuals with delusional disorders while they are awake


Sleep• Lucid dreaming

– A dream during which the dreamer is aware of dreaming and is often able to influence the content of the dream while it is in progress

– Research suggests that individuals who are good at controlling their thoughts when awake are also successful at lucid dreaming


Sleep• Interpreting dreams

– Sigmund Freud• Believed that dreams function to satisfy

unconscious sexual and aggressive wishes

• Manifest content: Freud’s term for the content of a dream as recalled by the dreamer

• Latent content: Freud’s term for the underlying meaning of a dream


Sleep

• Interpreting dreams (continued)– In recent years, the focus has shifted away

from the Freudian interpretation of dreams to the manifest content

– J. Allan Hobson• Rejects the notion that nature would equip

humans with a capability and a need to dream dreams that would require a specialist to interpret


Sleep

• Interpreting dreams (continued)

– Activation-synthesis hypothesis

• Advanced by Hobson and McCarley

• The hypothesis that dreams are the brain’s attempt to make sense of the random firing of brain cells during REM sleep

– Hobson believes that dreams also have psychological significance, because the meaning a person imposes reflects that person’s experiences, remote memories, associations, drives, and fears


Sleep

• Sleep disorders– Parasomnias

• Sleep disturbances in which behaviors and psychological states that normally occur only in the waking state take place during sleep

–Somnambulism: Sleepwalking; occurs during partial arousal from Stage 4 sleep


Sleep– Sleep terrors

• Happen during a partial arousal from Stage 4 sleep

• Usually begin with a piercing scream and the sleeper springs up in a state of panic with open eyes

• The sleeper is perspiring, breathing rapidly, with the heart pounding at two or more times the normal rate


Sleep

• Sleep disorders (continued)– Nightmares

• Frightening dreams that occur during REM sleep and are likely to be remembered in vivid detail

– Somniloquy• Sleep talking; can occur during any sleep

stage and is more frequent in children than adults


Sleep• Major sleep disorders

– Narcolepsy

• An incurable sleep disorder characterized by excessive daytime sleepiness and uncontrollable attacks of REM sleep, usually lasting 10 to 20 minutes

• People with narcolepsy are subject to more accidents virtually everywhere

• Caused by an abnormality in the part of the brain that regulates sleep, and it appears to have a strong genetic component


Sleep

• Major sleep disorders (continued)

– Sleep apnea

• Periods during sleep when breathing stops and the individual must awaken briefly in order to breathe

• The major symptoms are excessive daytime sleepiness and extremely loud snoring, often accompanied by snorts, gasps, and choking noises

• Alcohol and sedatives aggravate the condition


Sleep

• Sleep apnea (continued)– Can lead to chronic high blood pressure,

heart problems, and even death– Neuroscientists have also found that it can

cause mild brain damage– The interrupted sleep experienced by

individuals with this disorder affects cognitive as well as physiological functioning


Sleep• Major sleep disorders (continued)

– Insomnia• A sleep disorder characterized by difficulty

falling or staying asleep, by waking too early, or by sleep that is light, restless, or of poor quality

• Symptoms can lead to distress and impairment in daytime functioning

• Transient (temporary) insomnia lasts for 3 weeks or less

• Chronic insomnia lasts for months or even years and plagues about 10% of the adult population


Meditation and Hypnosis

• Meditation

– A group of techniques that involve focusing attention on an object, a word, one’s breathing, or body movement in order to block out all distractions, to enhance well-being, and to achieve an altered state of consciousness



• Meditation Techniques– Yoga

• A meditator typically assumes a cross-legged position known as the lotus and gazes at a visual stimulus, a mandala or an object such as a vase or flower

– Zen• The individual counts breaths or

concentrates on the breathing process



• Meditation techniques (continued)

– Transcendental

• The meditator is given a mantra which he or she repeats over and over during meditation

– Herbert Benson

• Claims that the beneficial effects of meditation can be achieved through simple relaxation techniques


Meditation and Hypnosis• Benson’s relaxation steps

–Step 1: Find a quiet place and sit in a comfortable position.

–Step 2: Close your eyes.

–Step 3: Relax all your muscles deeply. Begin with your feet and move slowly upward, relaxing the muscles in your legs, buttocks, abdomen, chest, shoulders, neck, and finally your face. Allow your whole body to remain in this deeply relaxed state.


Meditation and Hypnosis• Benson’s relaxation steps (continued)

– Step 4: Now concentrate on your breathing, and breathe in and out through your nose. Each time you breathe out, silently say the word “one” to yourself. If a distracting thought comes to mind, just ignore it.

– Step 5: Repeat this process for 20 minutes. (You can open your eyes to look at your watch periodically, but don’t use an alarm.) When you are finished, remain seated for a few minutes, first with your eyes closed, then with them open.



• Benson’s relaxation steps (continued)

–Step 6: Practice this exercise one or two times each day, but not within two hours of your last meal. Digestion interferes with the relaxation response.


Meditation and Hypnosis• Meditation (continued)

– Researchers have found that regular meditation helps individuals, even those who are severely depressed, learn to control their emotions

– Meditation may lower blood pressure, cholesterol levels, and other measures of cardiovascular health

– Meditation may be an important component of a comprehensive approach to preventing and treating cardiovascular disease


Meditation and Hypnosis• Hypnosis

– A procedure through which one person, the hypnotist, uses the power of suggestion to induce changes in thoughts, feelings, sensations, perceptions, or behavior in another person, the subject

– About 80–95% of people are hypnotizable to some degree, but only 5% can reach the deepest levels of the hypnotic state

– Silva and Kirsch• Found that individuals’ fantasy-proneness

and their expectation of responding to hypnotic suggestions were predictors of hypnotizability



Myths about hypnosis• Hypnotized people are under the complete

control of the hypnotist and will violate their moral values if told to do so.

• People can demonstrate superhuman strength and perform amazing feats under hypnosis.

• Memory is more accurate under hypnosis.• People under hypnosis will reveal

embarrassing secrets.• People under hypnosis can relive an event

that occurred when they were children and can function mentally as if they were that age.



Medical Uses of Hypnosis• Hypnosis is accepted by the American Medical

Association, the American Psychological Association, and the American Psychiatric Association.

• Hypnosis has been particularly helpful in the control of pain.

• Hypnosis has also been used successfully to treat a wide range of disorders.

• For the most hypnotizable people, hypnosis can be used instead of general anesthesia in surgery.


Meditation and HypnosisTheories of hypnosis

• Sociocognitive theory of hypnosis

• Suggests that the behavior of a hypnotized person is a function of that person’s expectations about how subjects behave under hypnosis

• Kinnunen and others

–Used skin conductance to indicate whether a person was truly hypnotized

–Found that 89% of supposedly hypnotized people had been truly hypnotized



Theories of hypnosis (continued)

• Neodissociation theory of hypnosis

• A theory proposing that hypnosis works by causing a split, or dissociation, between two aspects of the control of consciousness; the planning and the monitoring functions

• Proposed by Ernest Hilgard

• Hilgard called the monitoring function, when separated from conscious awareness, “the hidden observer”



Theories of hypnosis (continued)• Theory of dissociated control

• The theory that hypnosis is an authentic altered state of consciousness in which the control the executive function exerts over other subsystems of consciousness is weakened

• Proposed by Bowers and his colleagues

• Kihlstrom suggested that a more complete picture of hypnosis would emerge from some combination of the sociocognitive and neodissociation theories.


Meditation and HypnosisCulture and altered states of consciousness

• In every culture around the world, and throughout recorded history, human beings have found ways to induce altered states of consciousness.

• Entering ritual trances and experiencing spirit possession are forms of altered states of consciousness used in many cultures in the course of religious rites and tribal ceremonies

• People induce a ritual trance by flooding the senses with repetitive chanting, clapping, or singing; by whirling in circles until they achieve a dizzying speed; or by burning strong, pungent incense


Psychoactive Drugs

Psychoactive drug

– Any substance that alters mood, perception, or thought

– Called a controlled substance if approved for medical use

– The term “illicit” denotes psychoactive drugs that are illegal

– Many over-the-counter drugs are psychoactive


Psychoactive DrugsHow drugs affect the brain

• Researchers have found that a surge of dopamine is involved in the rewarding and motivational effects produced by most psychoactive drugs.

• Each drug influences the whole system differently and is associated with an altered state of consciousness.

• Opiates such as morphine and heroin mimic the effects of the brain’s own endorphins, chemicals that have pain-relieving properties and produce a feeling of well-being.


Psychoactive Drugs

How drugs affect the brain (continued)• Depressants, such as alcohol,

barbiturates, and benzodiazepines, act on GABA receptors to produce a calming, sedating effect.

• Thus, depressants can play a role in reducing a patient’s nervousness prior to undergoing a medical procedure.

• Stimulants such as amphetamines and cocaine mimic the effects of epinephrine, the neurotransmitter that triggers the sympathetic nervous system.


Psychoactive Drugs

• How drugs affect the brain (continued)– Drugs don’t always have solely beneficial

effects.– Too much of a good thing, or the wrong

combination of good things can lead to disaster.– Opiates, when taken regularly, will eventually

completely suppress the production of endorphins.

– As a result, natural pain management systems break down, and the brain becomes dependent on the presence of opiates to function normally


Psychoactive Drugs

Reasons for substance abuse• One possibility is that people are unaware of

just how harmful drugs can be.• Neurobiological factors

• The pleasant physiological states produced by stimulation of the nucleus accumbens are one reason for substance abuse.

• Brain-imaging studies have also shown that the irrationality caused by drugs’ effects on brain structures other than the nucleus accumbens is also a contributing factor.


Psychoactive Drugs

Reasons for substance abuse (continued)• Neurobiological factors (continued)

• It is now known that the irrational behavior of substance abuse is associated with dynamic changes in the orbitofrontal cortex and other brain structures to which it is connected.

• The orbitofrontal cortex is anatomically connected to the association areas for all five of your senses, to structures in the limbic system, and to other regions in the frontal cortex that handle decision making.


Psychoactive Drugs

Heredity

• People who have to drink more to experience intoxication are more likely to become alcoholics, and genetic researchers are currently searching for the gene or genes that contribute to low response to alcohol.

• The genetic underpinnings of alcoholism and other addictions appear to include physiological differences beyond those associated with drug responses.


Psychoactive Drugs• Heredity (continued)

• Henri Begleiter and his colleagues accumulated a large body of evidence suggesting that the brains of alcoholics respond differently to visual and auditory stimuli than those of nonalcoholics.

• Many relatives of alcoholics, even children and adults who have never consumed any alcohol in their lives, display the same types of response patterns.

• Relatives of alcoholics who display these patterns are more likely to become alcoholics or suffer from other types of addictions.


Psychoactive Drugs

Psychological and social factors• Impulsivity is associated with both

experimentation with drugs and addiction.• Stress-related variables are reliable

predictors of substance abuse.• Recent research indicates that family

violence strongly predicts drug use.• The earlier adolescents start using drugs

the more likely they are to progress to more serious drugs and full-blown addiction.


Psychoactive Drugs

Protective factors• Protective factors which tend to lower the

risk of drug use by young people include parental support, behavioral coping skills, and academic and social competence.

• Cultural variables contribute to protection from drug abuse as well.


Psychoactive Drugs

Drug addiction

• Substance abuse may be defined as continuing drug use that interferes with a person’s major life roles at home, in school, at work, or elsewhere and contributes to legal difficulties or any psychological problems.


Psychoactive Drugs

Drug addiction (continued)

• Four factors influence the addictive potential of a drug

• How fast the effects of the drug are felt

• How pleasurable the drug’s effects are in producing euphoria or in extinguishing pain

• How long the pleasurable effects last

• How much discomfort is experienced when the drug is discontinued


Psychoactive DrugsDrug addiction (continued)

• Physical drug dependence comes about as a result of the body’s natural ability to protect itself against harmful substances by developing a drug tolerance.

• Drug tolerance is a condition in which the user becomes progressively less affected by the drug so that larger and larger doses are necessary to maintain the same effect.

• Withdrawal symptoms are the physical and psychological symptoms that occur when a regularly used drug is discontinued and that terminate when the drug is taken again.


Psychoactive Drugs

Drug addiction (continued)

• The lasting behavioral and cognitive effects of abused substances on the brain often interfere with attempts to stop using the substances.

• Researchers have learned that addiction is associated with attention and memory deficits, loss of the ability to accurately sense the passage of time, and a decline in the capacity to plan and control behavior


Psychoactive DrugsDrug addiction (continued)

• Psychological drug dependence is a craving or irresistible urge for a drug’s pleasurable effects.

• Continued use of drugs to which an individual is physically addicted is influenced by the psychological component of the habit.

• Learning processes are important in the development and maintenance of psychological dependence.


Psychoactive DrugsThe Behavioral Effects of Psychoactive Drugs

• Stimulants, often called “uppers,” are a category of drugs that speed up activity in the central nervous system, suppress appetite, and cause a person to feel more awake, alert, and energetic.

• Stimulants increase pulse rate, blood pressure, and respiration rate, and they reduce cerebral blood flow.

• In higher doses, stimulants make people feel nervous, jittery, and restless, and they can cause shaking or trembling and interfere with sleep.


Psychoactive Drugs

Stimulants (continued)– Caffeine

• Coffee, tea, cola drinks, chocolate, and more than 100 prescription and over-the-counter drugs contain caffeine

• Makes people more mentally alert and can help them stay awake

• When moderate to heavy caffeine users abstain, they can suffer withdrawal symptoms such as nervousness, instability, headaches, drowsiness, and decreased alertness

• Researchers were able to correlate the caffeine withdrawal symptoms with significant increases in blood pressure and in the velocity of blood flow in all four of the cerebral arteries; an increase in slower brain waves was also found


Psychoactive Drugs

Stimulants (continued)– Nicotine

• Increases alertness• Green & Lynn reviewed the results of

59 studies of hypnosis and smoking and concluded that hypnosis cannot be considered effective at helping smokers break the habit.


Psychoactive DrugsStimulants (continued)

– Amphetamines• Increase arousal, relieve fatigue, improve

alertness, suppress the appetite, and give a rush of energy

• Animal research suggests that amphetamines stimulate the release of dopamine in the frontal cortex as well as in the nucleus accumbens, which may account for some of their desirable cognitive effects, such as increases in attention span and concentration.



– Amphetamines continued• Can cause confused and disorganized

behavior, extreme fear and suspiciousness, delusions and hallucinations, aggressiveness and antisocial behavior, even manic behavior and paranoia

• Withdrawal leaves a person physically exhausted, sleeping for 10 to 15 hours or more, only to awaken in a stupor, extremely depressed and intensely hungry

• Over time high doses can stop blood flow, causing hemorrhaging and leaving parts of the brain deprived of oxygen



– Cocaine• Can be sniffed, injected or smoked• Stimulates the reward or “pleasure”

pathways in the brain, which use the neurotransmitter dopamine

• Continued use can cause these reward systems to fail to function normally

• Main withdrawal symptoms are psychological – the inability to feel pleasure and the craving for more cocaine


Psychoactive Drugs

Stimulants (continued)– Cocaine (continued)

• Constricts the blood vessels, raises blood pressure, speeds up the heart, quickens respiration, and can even cause epileptic seizures in people who have no history of epilepsy

– Crack cocaine• Most dangerous form of cocaine• Can produce a powerful dependency in

several weeks


Psychoactive Drugs

Depressants• A category of drugs that decrease activity

in the central nervous system, slow down bodily functions, and reduce sensitivity to outside stimulation

• Sometimes called “downers”• When different depressants are taken

together, their sedative effects are additive, and thus potentially dangerous


Psychoactive DrugsDepressants (continued)

– Alcohol• The more alcohol a person consumes, the

more the central nervous system is depressed

• Can cause men to become more aggressive and more sexually aroused, but less able to perform sexually

• Decreases the ability to form new memories• A drinker’s expectations contribute to

alcohol’s effects to some extent


Psychoactive Drugs• Depressants (continued)

– Barbiturates• Depress the central nervous system, and,

depending on the dose, a barbiturate can act as a sedative or a sleeping pill

• Abuse of barbiturates can cause drowsiness and confusion, thinking and judgment suffer, and coordination and reflexes are affected

• Overdose can cause death• When taken with alcohol, it is a potentially

fatal combination


Psychoactive Drugs

Depressants (continued)– Minor tranquilizers

• The popular minor tranquilizers, the benzodiazepines, are prescribed for several medical and psychological disorders.

• Abuse of these drugs is associated with both temporary and permanent impairment of memory and other cognitive functions.


Psychoactive DrugsDepressants (continued)

– Narcotics• Derived from the opium poppy, they

produce both a pain-relieving and a calming effect

• Opium affects mainly the brain but it also paralyzes the intestinal muscles, which is why it is used medically to treat diarrhea.

• Because opium suppresses the cough center, it is used in some cough medicines.


Psychoactive Drugs

Depressants (continued)– Narcotics (continued)

• Morphine and codeine, natural constituents of opium, may be found in some drugs prescribed for pain relief.

• A highly addictive narcotic derived from morphine is heroin.

• Heroin addicts describe a sudden “rush” of euphoria, followed by drowsiness, inactivity, and impaired concentration.


Psychoactive Drugs

Hallucinogens– A category of drugs, sometimes called

psychedelics, that alter perceptions of time and space, alter mood, produce feelings of unreality and also cause hallucinations

– Have been used in religious rituals and ceremonies and recreationally in diverse cultures since ancient times

– Hallucinogens usually magnify the mood of the user at the time the drug is taken

– They hamper rather than enhance creative thinking


Psychoactive DrugsHallucinogens (continued)

– Marijuana• THC, the ingredient in marijuana that

produces the high, remains in the body “for days or even weeks”

• Impairs attention and coordination and slows reaction time

• Can interfere with concentration, logical thinking, and the ability to form new memories

• Chronic use has been associated with loss of motivation, general apathy, and a decline in school performance – referred to as amotivational syndrome



– Marijuana (continued)• National Institute of Drug Abuse concluded

that marijuana shows promise as a treatment for certain medical conditions

• Has been found effective for treating the eye disease glaucoma, for controlling nausea and vomiting in cancer patients receiving chemotherapy, and for improving appetite and curtailing weight loss in some AIDS patients



– LSD (lysergic acid diethylamide)

• Sometimes referred to simply as “acid”

• Average LSD “trip” lasts for 10 to 12 hours and usually produces extreme perceptual and emotional changes, including visual hallucinations and feelings of panic

• On occasion, bad LSD trips have ended tragically in accidents, death, or suicide


Psychoactive Drugs

Hallucinogens (continued)– LSD continued

• A user can develop hallucinogen persisting perception disorder (HPPD)

–The visual cortex becomes highly stimulated whenever such individuals shut their eyes, causing them to experience chronic visual hallucinations whenever they try to sleep


Psychoactive Drugs

• Hallucinogens (continued)– Designer drugs

• Given this name because they are specifically formulated to mimic the pleasurable effects of other drugs without, supposedly, their negative side effects

• “STP” (serenity, tranquility, and peace) and “Ecstasy” are two common examples of designer drugs

• All designer drugs are derived from amphetamines, but have hallucinogenic as well as stimulant effects


Psychoactive Drugs• Hallucinogens (continued)

– Designer drugs (continued)– Ecstasy, or MDMA (methylene-dioxy-

methamphetamine)• Users describe a wonderfully pleasant state of

consciousness, in which even the most backward, bashful, self-conscious people shed their inhibitions

• MDMA is known to impair a variety of cognitive functions, including memory, sustained attention, analytical thinking, and self-control

• The drug is believed to have devastating effects on the critically important neurotransmitter, serotonin


Psychoactive Drugs

• Herbal Remedies and Supplements

– A survey of college students found that about half used herbal supplements.

– The use of herbs as medicines is an ancient practice that is still very common in some cultures.

– Many herbs have the same kinds of effects on the brain as drugs do.

– Research has yet to establish effective and safe dosages for herbal treatments.


Review of Learning Objectives

What is consciousness?

1. How have psychologists’ views about consciousness changed since the early days of psychology?



Circadian Rhythms• Which physiological and psychological

functions are influenced by circadian rhythms?• How do biological and environmental variables

influence circadian rhythms?• How can travelers combat the effects of jet lag?• In what ways does the disruption of circadian

rhythms affect shift workers?• How can research linking circadian rhythms

and neurological disorders be put to practical use?



Sleep1. How do NREM and REM sleep differ?2. What is the progression of NREM stages

and REM sleep in a typical night of sleep?

3. How do age and individual differences influence people’s sleep patterns?

4. What is the difference between the restorative and circadian theories of sleep?


Review of Learning ObjectivesSleep (continued)

5. How does sleep deprivation affect behavior and neurological functioning?

6. What have researchers learned about dreams, their content, their biological basis, and their controllability?

7. How do the views of contemporary psychologists concerning the nature of dreams differ from those of Freud?

8. What are the various disorders that can trouble sleepers?




1. What are the benefits of meditation?

2. What are the effects of hypnosis, and how do theorists explain them?

3. What is the connection between altered states of consciousness and culture?



Psychoactive Drugs1. How do drugs affect the brain’s

neurotransmitter system?2. What are some risk and protective factors for

substance abuse?3. What is the difference between physical and

psychological drug dependence?4. What are the effects of stimulants,

depressants, and hallucinogens on behavior?5. What are the pros and cons of using herbal

remedies?

psy i ch.4

Health & Medicine