I. Introduction: Consciousness: Experiencing the “Private I”
1. Your immediate awareness of thoughts, sensations, memories, and
the world around you represents the experience of consciousness.
2. American psychologist William James (1892) proposed that the
subjective experience of consciousness is an ongoing “river” or
“stream” of mental activity—always changing but perceived as
unified and unbroken.
a. In the late 1800s, the first psychologists tried to determine the
nature of the human mind through introspection, which meant
verbal self-reports that tried to capture the “structure” of
conscious experiences.
b. At the turn of the twentieth century, many of the leading
psychologists rejected the study of consciousness, emphasizing
instead the scientific study of overt behavior, which could be
directly observed, measured, and verified.
c. Beginning in the late 1950s, many psychologists again turned
their attention to the study of consciousness because a complete
understanding of behavior was not possible without considering
the role of conscious mental processes, and because new, more
objective ways to study conscious experience had been devised.
d. Today, the scientific study of consciousness takes into
account the role of psychological, physiological, social, and
cultural influences.
II. Biological and Environmental “Clocks” That Regulate
Consciousness
Circadian rhythms are the cyclical daily fluctuations in many different
biological and psychological processes. The cycle is roughly 24 hours long.
A. The Suprachiasmatic Nucleus: The Body’s Clock
1. The suprachiasmatic nucleus (SCN) is a tiny cluster of
neurons in the hypothalamus in the brain that governs the
timing of circadian rhythms.
2. Sunlight entrains, or sets, the SCN; that is, sunlight and other
bright light detected by visual receptors and processed by the
SCN suppress melatonin levels, whereas decreased light
increases the production of melatonin, a pineal gland hormone
that produces sleepiness.
B. Circadian Rhythms and Sunlight: The 24.2 Hour Day
1. Under free-running conditions (marked by an absence of all
environmental time cues)
a. people drift toward the natural rhythm of the
suprachiasmatic
nucleus, which is about 24.2 hours, or slightly longer
than a day.
b. people’s circadian rhythms lose their normal
synchronization with one another.
2. When people leave free-running conditions, sunlight “resets”
the biological clock within days, and their circadian rhythms
become synchronized again.
C. Circadian Rhythms and Sunlight: Some Practical Implications
1. You experience jet lag when your circadian rhythms are
drastically out of synchronization with daylight and darkness
cues. Symptoms include physical and mental fatigue,
depression or irritability, and disrupted sleep. In addition,
thinking, concentration, and memory become fuzzy.
2. People who work night shifts or rotating shifts often suffer
from jet lag symptoms.
III. Sleep
A. The Dawn of Modern Sleep Research:
Modern sleep research began with the invention of the EEG and the
discovery that sleep is a state marked by distinct physiological
processes and stages.
1. The invention of the electroencephalograph in the 1920s
gave sleep researchers an important tool for measuring the
rhythmic electrical activity of the brain. An
electroencephalograph produces a graphic record called an
EEG, or electroencephalogram.
2. The discovery of rapid-eye-movement sleep, abbreviated
REM sleep, in the early 1950s led researchers to distinguish
between two types of sleep.
a. REM sleep is often called active sleep or paradoxical
sleep because it is associated with heightened body and
brain activity during which dreaming consistently occurs.
b. NREM sleep, or non-rapid-eye-movement sleep, is
often referred to as quiet sleep because the body’s
physiological functions and brain activity slow down
during this period of slumber. NREM is
further divided into four stages.
B. The Onset of Sleep and Hypnagogic Hallucinations
1. Beta brain waves are the small, fast brain waves associated
with alert wakefulness.
2. Alpha brain waves are the slightly larger and slower waves
associated with relaxed wakefulness and drowsiness.
3. Hypnagogic hallucinations are vivid sensory phenomena
that can occur during the onset of sleep.
4. One common hypnagogic hallucination, the vivid sensation
of falling, is often accompanied by a myoclonic jerk, or sleep
start.
C. The First 90 Minutes of Sleep and Beyond
1. On average, the progression through the first four stages of
NREM sleep takes 50 to 70 minutes.
a. Stage 1 NREM sleep begins when alpha brain waves
are replaced by even slower theta brain waves. This stage
lasts only a few minutes.
b. Stage 2 NREM sleep represents the onset of true sleep.
It is defined by brief bursts of brain activity that last a
second or two, called sleep spindles, and K
complexes—single but large high-voltage spikes of brain
activity that occur periodically.
Theta waves predominate, but delta waves begin to
emerge.
c. Stage 3 and stage 4 of NREM sleep, sometimes
referred to as slow-wave sleep, are physiologically very
similar. Delta waves
represent an increasing proportion of total brain activity,
from 20 percent or more in stage 3 to 50 percent or more
in stage 4. In stage 4, the sleeper is virtually oblivious to
the world.
d. During REM sleep, visual and motor neurons in the
sleeper’s brain activate repeatedly just as they do during
wakefulness; the sleeper’s eyes dart back and forth
behind closed eyelids—rapid eye movements—and
voluntary muscle activity is suppressed.
Heart rate, blood pressure, and respirations can fluctuate
up and down, and muscle twitches occur.
e. Throughout the rest of the night, the sleeper cycles
between NREM and REM, with each cycle averaging
about 90 minutes, varying from 70 to 120 minutes.
Periods of REM sleep become
longer and less time is spent in NREM.
2. In Focus: What You Really Want to Know About Sleep
a. Yawning regulates and increases your level of arousal.
Thinking about yawning may trigger the behavior, but
yawning is not contagious.
b. Prolonged wakefulness results in a sharp increase in
adenosine levels and sleepiness. Slow-wave NREM sleep
reduces adenosine levels. Caffeine blocks adenosine
receptors, promoting wakefulness.
c. Sleep paralysis is a temporary condition in which a
person is unable to move upon awakening in the morning
or during REM sleep.
d. Deaf people who use sign language sometimes “sleep
sign” during sleep.
e. Sleep researchers have been unsuccessful in having
extended dialogues with people who talk in their sleep.
f. It is not dangerous to wake a sleepwalker, but it’s
difficult, because sleepwalkers are in deep sleep.
Sleepwalking may have a genetic component.
3. Over the course of our lives, the quantity and quality of sleep
change considerably.
a. From birth onward, total sleep time, REM sleep, and
NREM sleep slowly decrease.
b. The amount of time spent in slow-wave NREM sleep
(stages 3 and 4) also gradually decreases over the
lifespan.
D. Do We Need to Sleep?
1. A biological need for sleep is clearly demonstrated by sleep
deprivation studies; after as little as one night’s sleep
deprivation, research participants develop microsleeps, episodes
of sleep lasting only a few seconds during wakefulness.
a. People who go without sleep for a day or more
experience disruptions in mood, mental abilities, reaction
time, perceptual skills, and complex motor skills.
2. Sleep restriction (a reduction in the amount of time spent
sleeping) results in diminished concentration, vigilance,
reaction time, memory skills, and the ability to gauge risks. For
example:
a. decreased motor skills lead to greater accident risk,
b. moods become much more volatile,
c. the immune system’s effectiveness is diminished, and
d. all these changes become more pronounced if sleep
restriction continues night after night.
3. Sleep researchers also study the effects of REM and NREM
deprivation. When people are selectively deprived of REM
sleep, they experience REM rebound; when deprived of
NREM stages 3 and 4, they experience NREM rebound.
E. Why Do We Sleep?
1. Although numerous theories try to explain the purpose of
sleep, none is accepted as the definitive explanation.
2. The restorative theory of sleep suggests that sleep promotes
physiological processes that restore and rejuvenate the body and
the mind.
a. NREM sleep is important for restoring the body.
b. REM sleep is thought to restore mental and brain
functions.
3. The adaptive theory of sleep, or evolutionary theory
of sleep, suggests that sleep patterns evolved over time as
a way of preventing a particular species from interacting
with the environment when doing so is most hazardous.
4. Today’s researchers believe that studying sleep from
multiple perspectives—psychological, physiological, and
neurological—leads to a dynamic understanding of how
sleep occurs, is regulated, and how it contributes to
optimal functioning.
IV. Dreams and Mental Activity During Sleep
1. Adults spend about 25 percent of their nightly sleep—about
two hours—dreaming.
2. During sleep, repetitive, bland, uncreative ruminations about
reallife events, or sleep thinking, occur far more frequently
that dreams.
3. In contrast to sleep thinking, a dream is an unfolding
sequence of perceptions, thoughts, and emotions during sleep
that are experienced as a series of real-life events.
4. Most dreams occur during REM sleep, with people having
four or five episodes per night.
5. The brain’s activity during sleep distinctly differs from its
activity during wakefulness or NREM slow-wave sleep.
A. Sleep Memory Consolidation; Let Me Sleep on It!
1. An important activity during sleep is memory consolidation.
2. Episodic memories form during NREM sleep, and
procedural memories form during REM and NREM stage 2
sleep.
a. For example, new spatial memories learned before
sleep are not consolidated and enhanced by the passage
of time alone, but only after sleep. Also, sleep before
learning is critical to the formation
of new memories.
3. Focus on Neuroscience: The Dreaming Brain: Turning REM
On and Off
a. In contrast to the awake brain, or the brain in NREM
sleep, the sleeping brain undergoes distinct changes.
b. EEG records of brain electrical activity during sleep
show abrupt transitions from NREM to REM sleep
recurring through the night. REM sleep is characterized
by:
(1) decreased activity in the frontal lobes and the
primary visual cortext, thereby cutting dreamers
off from reality-testing functions of the frontal
lobe, which helps explain the bizarre
content of dreams.
(2) increased activity in association areas of the
visual cortex, giving rise to a dream’s visual
images.
(3) increased activity in limbic system brain areas
associated with emotion, motivation, and memory,
giving rise to the dream’s emotionality.
B. Dream Themes and Imagery: The Golden Horse in the Clouds
1. In Focus: What You Really Want to Know About Dreams
Some popular queries about dreams that researchers have
answered
to a greater or lesser degree include (1) do animals dream (yes,
the evidence suggests that they do); (2) what do blind people
“see” in their dreams? (people who are blind before the age of
5, typically do not have visual dreams, although their dreams
are as complex as those of sighted people); (3) can we control
our dreams? (yes, if they are lucid); (4) can our dreams predict
the future? (simply by chance, every now and then they can),
and (5) are our dreams in color? (up to 80 percent are).
2. Research shows that bizarre dreams are the exception, not the
rule.
3. Typical dreams include: negative feelings are more common
than positive ones; aggression is more common than
friendliness; dreamers are more likely to be victims of
aggression than aggressors; men have more dreams involving
physical aggression; women are more likely to report emotions
in their dreams; sex or sexual behaviors rarely appear; fear or
apprehension is the most frequently reported dream emotion for
both sexes.
4. The typical nightmare, a dream that wakens the dreamer, is
that of being aggressively attacked or pursued.
a. Nightmares occur most frequently during middle and
late childhood; then their frequency decreases.
b. In children’s nightmares, a common theme is being
attacked by an animal or monster.
c. About 5 percent to 10 percent of adults have weekly
nightmares.
d. Family and twin studies suggest some genetic role in
predisposition to nightmares.
C. The Significance of Dreams
1. Sigmund Freud: Dreams as Fulfilled Wishes
a. Sigmund Freud, the founder of psychoanalysis,
believed that dreams are manifestations or repressed
urges and wishes. They serve as a “safety valve” for
unconscious and unacceptable urges.
b. Freud suggested that dreams have two components: the
manifest content, or the dream images themselves, and
the latent content, the disguised psychological meaning
of the dreams.
c. While dreams may provide some information about
psychological conflicts, research does not support
Freud’s ideas about dreams.
2. The Activation–Synthesis Model of Dreaming
a. The activation–synthesis model of dreaming,
proposed by J. Allan Hobson and Robert McCarley,
maintains that dreaming is the brain’s synthesizing and
integrating of memory fragments, emotions, and
sensations that are internally triggered.
b. This theory does not state that dreams are meaningless.
Meaning is found by analyzing the way the dreamer
makes sense of the chaotic dream images.
3. Some Observations About the Meaning of Dreams
a. At least some of our dreams mirror our real-life
concerns and desires.
b. The more bizarre aspects of dream sequences may be
due to physiological changes in the brain during REM
and NREM sleep.
c. Some argue that dreaming consciousness is no
different from waking consciousness in its attempt to
make sense of the information that is available to it; only
the source of the information differs.
d. Because dream interpretations occur when were
awake, perhaps conscious speculations about dreams
reveal more about the psychological characteristics of the
interpreter than about the
dream itself.
V. Sleep Disorders: Troubled Sleep
Sleep disorders are serious disturbances in the normal sleep pattern
that interfere with daytime functioning and cause subjective distress.
Dysomnias are sleep disorders involving disruptions in the amount,
quality, and timing of sleep. Parasomnias are sleep disorders involving
undesirable physical arousal, behaviors, or events during sleep or sleep
transitions.
A. Insomnia: Fragmented, Dissatisfying Sleep
1. The most common sleep complaint among adults, insomnia
is the inability to fall asleep, stay asleep, or feel adequately
rested by sleep.
2. Women are twice as likely to suffer from insomnia as men,
and it also increases with age.
3. Insomnia is linked to hyperarousal, which may be caused,
for example, by physical pain, depression, medications,
common stimulants like caffeine, or environmental factors like
noise.
4. More commonly, insomnia may be traced to anxiety over
stressful life events.
B. Obstructive Sleep Apnea
1. In obstructive sleep apnea (OSA), the second most common
sleep disorder, especially in overweight men over 50, the
sleeper repeatedly stops breathing during sleep.
2. OSA tends to run in families and is twice as common in men
as women.
3. OSA increases other serious health risks, such as for heart
attack.
4. OSA is usually treated with continuous positive airway
pressure (CPAP).
C. Narcolepsy: Blurring the Boundaries Between Sleep and
Wakefulness
1. Narcolepsy, a chronic lifelong condition that typically
begins in adolescence, is characterized by excessive daytime
sleepiness and brief lapses into sleep throughout the day.
a. The onset of daytime sleep episodes is sometimes
accompanied by frightening hypnagogic hallucinations;
as people awaken, they may experience sleep paralysis.
b. Narcolepsy is often characterized by episodes of
cataplexy—sudden loss of voluntary muscle strength and
control.
c. People with narcolepsy can also experience sleep
paralysis when going to sleep or when waking.
d. Narcolepsy occurs in every culture and ethnic group,
affecting males and females equally and is also a lifelong
chronic condition.
e. Multiple factors seem to play a causal role, including
chromosomal, brain, neurotransmitter, and immune
system abnormalities. While narcolepsy cannot be cured,
new drugs such as modafinil reduce daytime sleepiness.
D. The Parasomnias: Undesired Arousal or Actions During Sleep
Generally, parasomniacs arise during NREM sleep stages 3 and 4
slow-wave sleep; occur most commonly in children; seem to have
some genetic predisposition or susceptibility; and can be triggered by
a broad range of stimuli. Sleep researchers still do not fully
understand the various mechanisms involved in the parasomnias.
1. Sleep Terrors
a. Night terrors, or sleep terrors, are characterized by
sharply increased physiological arousal, intense fear and
panic, frightening hallucinations, and no recall of the
episode the next morning.
b. Sleep terrors are typically brief, lasting only seconds.
In most children, the problem resolves itself by early
adolescence.
2. Sleepsex
a. Sexsomnia, or sleepsex, involves abnormal sexual
behaviors and experiences during sleep, such as
masturbation, or sexual intercourse.
b. Sleepsex occurs more commonly in men than women
and is a chronic condition, usually beginning in early
adulthood.
c. Sleepsex can have undesirable consequences, such as
strain on a relationship.
3. Sleepwalking
a. Sleepwalking, or somnambulism, is characterized by
an episode of walking or performing other actions during
stage 3 or stage 4 NREM sleep. Most sleepwalkers are
children, but about 4 percent of adults sleepwalk.
b. A sleepwalker’s behavior can range from calm to
agitated, but the behavior is more usually fairly harmless.
4. Sleep-Related Eating Disorder (SRED)
a. In sleep-related eating disorder, the sleeper
sleepwalks, during which he or she eats compulsively.
b. Twice as many females as males suffer from SRED,
which poses potential dangers such as eating bizarre
items like cat food; there is also the risk of serious injury,
with people using kitchen equipment when sleeping,
while other negative effects may include weight, gain,
dental problems, and social embarrassment.
5. Critical Thinking: Sleep Related Violence: Is Sleep Murder
Possible?
a. About 2 percent of adults report violent activity during
sleep. When someone claims that he or she has
committed a violent act
during sleepwalking, sleep researchers suggest some
guidelines in assessing whether these claims are truthful.
b. The guidelines include asking whether (1) there is a
reason to suggest a real sleep disorder, (2) there is no
apparent motivation,
(3) the sleep-related violence was triggered by
precipitating factors such as medications or fever, (4) the
victim merely happened to be present, (5) there is some
degree of amnesia about the event, (6) the person seems
unaware during the event and is
horrified or perplexed after it, and (7) the event’s
duration is brief, typically several minutes in length.
6. REM Sleep Behavior Disorder (RBD)
a. In REM sleep behavior disorder, the sleeper
(typically a man over 50) acts out his dreams. The
disorder has several possible causes.
(1) Evidence suggests that the cause is
deterioration or damage in the lower brain centers
that control physical and mental arousal during
sleep.
(2) It can also be a side effect of antidepressant and
other medications.
(3) In some cases, people with REM sleep
behavior disorder have later developed a
neurological disorder, such as Parkinson’s disease.
VI. Hypnosis
1. Hypnosis is a cooperative social interaction in which the
hypnotic participant responds to the hypnotist’s suggestions
with changes in perception, memory, thoughts, and behavior.
2. Hypnosis, which is not a sleeplike trance, is characterized by
highly focused attention, increased responsiveness to
suggestions, vivid images and fantasies, a willingness to accept
distortions of logic or reality, and a voluntary acceptance of the
hypnotist’s instructions.
3. The best candidates for hypnosis are individuals who
approach the hypnotic experience with positive, receptive
attitudes and the expectation that they will be responsive to
hypnosis.
A. Effects of Hypnosis
1. Sensory and Perceptual Changes
a. Hypnotized subjects sometimes experience profound
sensory and perceptual changes, including hallucinations.
b. Behavior outside the hypnotic state may be influenced
by posthypnotic suggestion, a suggestion made during
hypnosis that the person carry out a specific instruction
following the hypnotic session. Most of these last a few
days or hours.
2. Hypnosis and Memory
a. Posthypnotic amnesia is the inability to recall specific
information or events that occurred before or during
hypnosis because of a hypnotic suggestion.
b. In hypermnesia, a hypnotic suggestion supposedly
enhances a person’s memory for past events. However,
hypnosis does not significantly enhance memory or
improve the accuracy of memories.
c. Hypnosis can greatly increase confidence in memories
that are actually incorrect. False memories, or
pseudomemories, can be created when hypnosis is used
to aid recall.
B. Explaining Hypnosis: Consciousness Divided?
1. Ernest R. Hilgard believed that the hypnotized person
experiences dissociation, the splitting of consciousness into two
or more simultaneous streams of mental activity.
2. According to Hilgard’s neodissociation theory of hypnosis,
a hypnotized person consciously experiences one stream of
mental activity that is responding to the hypnotist’s suggestions,
while a second, dissociated stream of mental activity is also
operating. Hilgard used the term hidden observer for the
second, dissociated stream of mental activity.
3. Critical Thinking: Is Hypnosis a Special State of
Consciousness?
a. The “state” explanation, represented by Hilgard’s
theory, contends hat hypnosis is a unique state of
consciousness.
b. The “non-state” view rejects the idea that hypnosis is a
special state of consciousness and contends that hypnosis
can be explained in terms of ordinary psychological
processes.
c. According to the social-cognitive view of hypnosis,
subjects are responding to the social demands of the
hypnosis situation.
d. Using PET scans, researchers compared brain activity
in participants who were instructed to change the color of
the images they were viewing. Brain activity reflected the
hypnosis-induced hallucinations,
not the actual images shown to the hypnotized
participants. This study supports the state theory of
hypnosis.
e. The imaginative suggestibility view maintains that the
effects of hypnosis are due to individual differences in
people’s ability to experience an imaginary state of
affairs as if it were real.
4. Limits and Applications of Hypnosis
a. A person cannot be hypnotized against his or her will.
b. Hypnosis cannot make you perform behaviors that are
contrary to your morals and values.
c. Hypnosis cannot make you stronger than your physical
capabilities or bestow new talents, although hypnosis can
enhance physical skills or athletic ability by increasing
motivation and concentration. It can also help to modify
problematic behaviors.
VII. Meditation
Meditation refers to a group of techniques that induce an altered state of
focused attention and heightened awareness. Meditation techniques can be
divided into two basic categories:
1. Concentration techniques involve focusing awareness on a
visual image, your breathing, a word, or a phrase (called a
mantra) that is repeated mentally.
2. Opening-up techniques involve a present-centered awareness
of the passing moment, without mental judgment.
3. Some meditative traditions also stress the attainment of
emotional control. This has prompted investigations into the
effectiveness of meditation for relieving anxiety and improving
physical and psychological health.
A. Effects of Meditation
1. Even beginning meditators practicing transcendental
meditation, or TM (a concentration technique) experience a
state of lowered physiological arousal, including lowered blood
pressure, a decrease in heart rate, and changes in brain waves.
2. Many studies have shown that regular meditation can
enhance physical and psychological functioning beyond that
provided by relaxation alone.
VIII. Psychoactive Drugs
Psychoactive drugs are chemical substances that can alter arousal, mood,
thinking, sensation, and perception.
A. Common Properties of Psychoactive Drugs
1. Addiction is a broad term that refers to a condition in which a
person feels psychologically and physically compelled to take a
specific drug.
2. Physical dependence is a condition in which a person’s
body and brain chemistry have physically adapted to a drug.
3. Many physically addictive drugs gradually produce drug
tolerance, a condition in which increasing amounts of the drug
are needed to produce the original, desired effect.
4. Withdrawal symptoms are unpleasant physical reactions to
the lack of the drug, plus an intense craving for it.
5. The drug rebound effect is the experience of withdrawal
symptoms that are opposite to the drug’s action.
6. Psychoactive drugs influence brain activity by altering
synaptic transmission among neurons through increasing or
decreasing neurotransmitter amounts or by blocking,
mimicking, or influencing anarticular neurotransmitter’s
effects. Psychological and environmental factors can influence
the effects of a drug.
8. Drug abuse refers to recurrent drug use that results in
disrupted academic, social, and occupational functioning or in
legal and psychological problems.
9. Determining whether there is drug abuse is influenced by a
variety of factors, including different ethnic norms regarding
the use of alcohol.
10. Focus on Neuroscience: The Addicted Brain: Diminishing
Rewards
a. Addictive drugs activate the dopamine-producing
neurons in the brain’s reward system. The initial
dopamine surge in response to drug use is the internal
reinforcing reward, prompting the person to take the drug
again.
b. With repeated drug use, the brain’s reward pathways
adapt to the high dopamine levels. The availability of
dopamine receptors is greatly reduced, and other
biochemical changes inhibit the
brain’s reward circuits, resulting in drug tolerance. The
brain’s diminished reward circuits also produce
depression and negative emotional states.
c. Withdrawal and craving may be caused by reward
circuits that have become hypersensitive to the abused
substance.
B. The Depressants: Alcohol, Barbiturates, and Tranquilizers
The depressants are a class of psychoactive drugs that depress or
inhibit central nervous system activity. All depressants are potentially
physically addictive. The effects of depressant drugs are additive.
1. Alcohol
a. Alcohol, used in small amounts, reduces tension and
anxiety. Light drinking reduces the risk of heart disease.
b. A survey found that some 16 million people age 12
and older were dependent upon or abused alcohol.
c. Alcohol depresses the activity of neurons throughout
the brain and impairs cognitive abilities such as
concentration, memory, and speech, as well as physical
abilities such as muscle coordination and balance.
d. The negative effects associated with binge drinking
(five drinks in a row for men, four or more in a row for
women) include aggressive behavior, sexual assault,
accidents, and property damage.
e. Because alcohol is physically addictive, the person
with alcoholism who stops drinking may suffer from
physical withdrawal symptoms, the severity of which
depends on the level of physical dependence—from “the
shakes” to severe symptoms called delirium tremens, or
the DTs.
f. Alcohol lessens inhibitions by depressing the brain
centers that govern judgment and self-control.
2. Inhalants
a. Inhalants are chemical substances that are inhaled to
produce an alteration in consciousness.
b. Inhalants generally depress the central nervous system.
c. Inhalants are very dangerous, with hazards including
suffocation as well as toxicity to the liver and other
organs.
3. Barbiturates and Tranquilizers
a. Barbituras depress activity in the brain centers that
control arousal, wakefulness, and alertness. They also
depress the brain’s respiratory centers. Barbiturates at
low doses cause relaxation, mild euphoria, and reduced
inhibitions. Larger doses produce a loss of coordination,
impaired mental functioning, and depression. High doses
can produce unconsciousness, coma, and death.
Barbiturate include the prescription drugs Seconal and
Nembutal and the illegal drug methaqualone.
b. Tranquilizers are depressants that relieve anxiety. The
effects are similar to, but less powerful than, those
produced by barbiturates. Common prescription
tranquilizers are Xanax, Valium, Librium, and Ativan.
C. The Opiates: From Poppies to Demerol
1. Often called narcotics, opiates are a group of addictive drugs
that relieve pain and produce feelings of euphoria. Opiates
include opium, morphine, codeine, heroin, methadone, and
some prescription pain killers (such as OxyContin, Percodan,
and Demerol). Opiates produce their powerful effects by
mimicking the brain’s own natural painkillers, called
endorphins.
2. Among the most dangerous opiates is heroin. Injecting
heroin creates an intense rush of euphoria, followed by feelings
of contentment, peacefulness, and warmth. Withdrawing from
heroin produces unpleasant drug rebound symptoms. Heroin is
not, however, the most abused opiate; oxycontin is. In terms of
illicit use, prescription pain pills are second only to marijuana.
D. The Stimulants: Caffeine, Nicotine, Amphetamines, and Cocaine
Stimulants are at least mildly addicting, and all tend to increase brain
activity.
1. Caffeine and nicotine
a. Caffeine, found in coffee, tea, cola drinks, chocolate,
and many over-the-counter medications, increases mental
alertness and wakefulness. It is the most widely used
psychoactive drug in the world and it is physically
addictive.
b. High doses of caffeine can produce anxiety,
restlessness, insomnia, and increased heart rate.
c. Nicotine, an extremely addictive stimulant, is found in
all tobacco products. It increases mental alertness and
reduces fatigue or drowsiness.
2. Amphetamines and Cocaine
a. Amphetamines elevate mood and suppress appetite.
Included are benzedrine, dexedrine, and
methamphetamine.
(1) Methamphetamine, or meth, is an illegal drug
manufactured in home or street laboratories.
(2) PET scans of former meth users show a
significant reduction in the number of dopamine
receptors and transporters. Memory and motor
skill problems are common in former abusers and
are most severe in those with the greatest loss of
dopamine transporters.
3. Focus on Neuroscience: How Methamphetamines Erode the
Brain
a. MRI scans of chronic meth users show tissue loss in
the limbic system areas involved in emotion and reward,
as well as in hippocampal regions involved in learning
and memory.
4. Cocaine is an illegal stimulant, which is “snorted” or inhaled
in a powdered form; a more concentrated form called crack is
smoked. Inhaling cocaine produces intense euphoria, mental
alertness, and self-confidence, which last for several minutes.
5. Prolonged use of amphetamines or cocaine can result in
schizophrenia- like symptoms called stimulant-induced
psychosis (also called amphetamine psychosis or cocaine
psychosis).
E. Psychedelic Drugs: Mescaline, LSD, and Marijuana
Psychedelic drugs create sensory and perceptual distortions, alter
mood, and affect thinking.
1. Mescaline and LSD
a. Mescaline is a naturally occurring psychedelic drug
derived from the peyote cactus. Another psychedelic
drug, psilocybin, is derived from the Psilocybe
mushroom and is sometimes called
“magic mushrooms.”
b. LSD (lysergic acid diethylamide) is a powerful
synthetic psychedelic drug. LSD and psilocybin are very
similar chemically to the neurotransmitter serotonin,
which is involved in regulating moods and sensations.
c. The effects of a psychedelic experience vary greatly,
depending on an individual’s personality, current
emotional state, surroundings, and the other people
present. Adverse reactions include flashbacks,
depression, and long-term psychological instability.
2. Marijuana
a. Marijuan a is derived from the hemp plant, Cannibis
sativa, and is one of the most widely used illegal drugs.
b. The chemical tetrahydrocannabinol, abbreviated THC,
is the active ingredient in marijuana. One potent form of
marijuana, hashish, is made from the resin of the hemp
plant.
c. Researchers discovered receptor sites in the brain that
are specific for THC. They also discovered a naturally
occurring brain chemical called anandamide, which is
structurally similar to THC and which binds to the THC
receptors in the brain. Anandamide may reduce painful
sensations.
d. Most marijuana users do not develop tolerance or
physical dependence.
e. Marijuana and its ingredient THC have been shown to
be helpful in treating some medical conditions, as well as
preventing the negative effects of chemotherapy.
f. Marijuana interferes with muscle coordination and
perception and may impair driving ability. Alcohol
intensifies its effects.
F. Designer “Club” Drugs: Ecstasy and the Dissociative Anesthetic
Drugs “Club drugs” are a loose collection of psychoactive drugs that
are popular at dance clubs, parties, and “raves.” Many are designer
drugs, that is, drugs that were synthesized in the laboratory.
1. Ecstasy, which is the chemical MDMA, at low doses has
stimulant effects; at high doses, it has mild psychedelic effects.
a. Ecstasy, at high doses, produces feelings of euphoria
and increased well-being, as well as feelings of love and
openness to others.
b. Side effects include dehydration, rapid heartbeat,
tremors, muscle tension and involuntary teeth-clenching,
and hyperthermia.
c. Ecstasy’s effects may result from its causing the
release of serotonin and its ability to block serotonin
reuptake.
d. Several studies have shown potentially irreversible
damage to serotonin nerve endings in the brain. Longterm effects include depression and problems with
memory and verbal reasoning.
2. Dissociative anesthetics deaden pain; at high doses, they can
induce a stupor or coma.
a. PCP (angel dust) and ketamine (special K) produce
marked feelings of dissociation and depersonalization.
b. PCP’s effects are unpredictable. High doses can cause
hyperthermia, convulsions, and death.
c. PCP is highly addictive. Memory problems and
depression are common effects of long-term use.
IX. Application: Can’t Sleep? Read This!
1. Preventing Sleep Problems
a. Monitor your intake of stimulants.
b. Establish a quiet bedtime routine.
c. Create the conditions for restful sleep.
d. Establish a consistent sleep/wake schedule.
2. Stimulus Control Therapy
a. Stimulus control therapy is a technique you can
implement on your own for treating insomnia.
b. It is designed to help you establish a consistent sleep–
wake schedule and associate your bedroom and bedtime
with falling asleep.
3. Relaxation Training
a. Progressive relaxation is a simple procedure that
involves tensing a specific muscle group for about 10
seconds, then releasing the tension while exhaling slowly
and deeply.
b. Autogenic training involves repeating a specific
sequence of statements to induce deep relaxation.