psychological science disscussions
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Chapter 5
States of Consciousness An Unconscious Killing
During the night of May 23, 1987, Kenneth Parks, a 23-year old Canadian with a wife, a baby daughter, and heavy
gambling debts, got out of his bed, climbed into his car, and drove 15 miles to the home of his wife’s parents in the
suburbs of Toronto. There, he attacked them with a knife, killing his mother-in-law and severely injuring his father-
in-law. Parks then drove to a police station and stumbled into the building, holding up his bloody hands and saying, “I
think I killed some people…my hands.” The police arrested him and took him to a hospital, where surgeons repaired
several deep cuts on his hands. Only then did police discover that he had indeed assaulted his in-laws.
Parks claimed that he could not remember anything about the crime. He said that he remembered going to sleep in
his bed, then awakening in the police station with bloody hands, but nothing in between. His defense was that he had
been asleep during the entire incident and was not aware of his actions (Martin, 2009). [1]
Not surprisingly, no one believed this explanation at first. However, further investigation established that he did have
a long history of sleepwalking, he had no motive for the crime, and despite repeated attempts to trip him up in
numerous interviews, he was completely consistent in his story, which also fit the timeline of events. Parks was
examined by a team of sleep specialists, who found that the pattern of brain waves that occurred while he slept was
very abnormal (Broughton, Billings, Cartwright, & Doucette, 1994). [2]
The specialists eventually concluded that
sleepwalking, probably precipitated by stress and anxiety over his financial troubles, was the most likely explanation
of his aberrant behavior. They also agreed that such a combination of stressors was unlikely to happen again, so he
was not likely to undergo another such violent episode and was probably not a hazard to others. Given this
combination of evidence, the jury acquitted Parks of murder and assault charges. He walked out of the courtroom a
free man (Wilson, 1998). [3]
Consciousness is defined as our subjective awareness of ourselves and our environment (Koch,
2004). [4]
The experience of consciousness is fundamental to human nature. We all know what it
means to be conscious, and we assume (although we can never be sure) that other human beings
experience their consciousness similarly to how we experience ours.
The study of consciousness has long been important to psychologists and plays a role in many
important psychological theories. For instance, Sigmund Freud’s personality theories
differentiated between the unconscious and the conscious aspects of behavior, and present-day
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psychologists distinguish betweenautomatic (unconscious) and controlled (conscious) behaviors
and betweenimplicit (unconscious) and explicit (conscious) memory (Petty, Wegener, Chaiken,
& Trope, 1999; Shanks, 2005). [5]
Some philosophers and religious practices argue that the mind (or soul) and the body are separate
entities. For instance, the French philosopher René Descartes (1596–1650) was a proponent
of dualism, the idea that the mind, a nonmaterial entity, is separate from (although connected to)
the physical body. In contrast to the dualists, psychologists believe that consciousness (and thus
the mind) exists in the brain, not separate from it. In fact, psychologists believe that
consciousness is the result of the activity of the many neural connections in the brain, and that
we experience different states of consciousness depending on what our brain is currently doing
(Dennett, 1991; Koch & Greenfield, 2007). [6]
The study of consciousness is also important to the fundamental psychological question
regarding the presence of free will. Although we may understand and believe that some of our
behaviors are caused by forces that are outside our awareness (i.e., unconscious), we
nevertheless believe that we have control over, and are aware that we are engaging in, most of
our behaviors. To discover that we, or even someone else, has engaged in a complex behavior,
such as driving in a car and causing severe harm to others, without being at all conscious of
one’s actions, is so unusual as to be shocking. And yet psychologists are increasingly certain that
a great deal of our behavior is caused by processes of which we are unaware and over which we
have little or no control (Libet, 1999; Wegner, 2003). [7]
Our experience of consciousness is functional because we use it to guide and control our
behavior, and to think logically about problems (DeWall, Baumeister, & Masicampo,
2008). [8]
Consciousness allows us to plan activities and to monitor our progress toward the goals
we set for ourselves. And consciousness is fundamental to our sense of morality—we believe
that we have the free will to perform moral actions while avoiding immoral behaviors.
But in some cases consciousness may become aversive, for instance when we become aware that
we are not living up to our own goals or expectations, or when we believe that other people
perceive us negatively. In these cases we may engage in behaviors that help us escape from
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consciousness, for example through the use of alcohol or other psychoactive drugs (Baumeister,
1998). [9]
Because the brain varies in its current level and type of activity, consciousness is transitory. If we
drink too much coffee or beer, the caffeine or alcohol influences the activity in our brain, and our
consciousness may change. When we are anesthetized before an operation or experience a
concussion after a knock on the head, we may lose consciousness entirely as a result of changes
in brain activity. We also lose consciousness when we sleep, and it is with this altered state of
consciousness that we begin our chapter.
[1] Martin, L. (2009). Can sleepwalking be a murder defense? Sleep Disorders: For Patients and Their Families. Retrieved
from http://www.lakesidepress.com/pulmonary/Sleep/sleep-murder.htm
[2] Broughton, R. J., Billings, R., Cartwright, R., & Doucette, D. (1994). Homicidal somnambulism: A case report. Sleep: Journal of
Sleep Research & Sleep Medicine, 17(3), 253–264.
[3] Wilson, C. (1998). The mammoth book of true crime. New York, NY: Robinson Publishing.
[4] Koch, C. (2004). The quest for consciousness: A neurobiological approach. Englewood, CO: Roberts & Co.
[5] Petty, R., Wegener, D., Chaiken, S., & Trope, Y. (1999). Dual-process theories in social psychology. New York, NY: Guilford
Press; Shanks, D. (2005). Implicit learning. In K. Lamberts (Ed.), Handbook of cognition (pp. 202–220). London, England: Sage.
[6] Dennett, D. C. (1991). Consciousness explained. Boston, MA: Little, Brown and Company; Koch, C., & Greenfield, S. (2007).
How does consciousness happen? Scientific American, 76–83.
[7] Libet, B. (1999). Do we have free will? Journal of Consciousness Studies, 6, 8(9), 47–57; Wegner, D. M. (2003). The mind’s
best trick: How we experience conscious will. Trends in Cognitive Sciences, 7(2), 65–69.
[8] DeWall, C., Baumeister, R., & Masicampo, E. (2008). Evidence that logical reasoning depends on conscious
processing. Consciousness and Cognition, 17(3), 628.
[9] Baumeister, R. (1998). The self. In The handbook of social psychology (4th ed., Vol. 2, pp. 680–740). New York, NY: McGraw-
Hill.
5.1 Sleeping and Dreaming Revitalize Us for Action L E A R N I N G O B J E C T I V E S
1. Draw a graphic showing the usual phases of sleep during a normal night and notate the characteristics of each phase.
2. Review the disorders that affect sleep and the costs of sleep deprivation.
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3. Outline and explain the similarities and differences among the different theories of dreaming.
The lives of all organisms, including humans, are influenced by regularly occurring cycles of
behaviors known as biological rhythms. One important biological rhythm is the annual cycle that
guides the migration of birds and the hibernation of bears. Women also experience a 28-day
cycle that guides their fertility and menstruation. But perhaps the strongest and most important
biorhythm is the daily circadian rhythm (from the Latin circa, meaning ―about‖ or
―approximately,‖ and dian, meaning ―daily‖) that guides the daily waking and sleeping cycle in
many animals.
Many biological rhythms are coordinated by changes in the level and duration of ambient light,
for instance, as winter turns into summer and as night turns into day. In some animals, such as
birds, the pineal gland in the brain is directly sensitive to light and its activation influences
behavior, such as mating and annual migrations. Light also has a profound effect on humans. We
are more likely to experience depression during the dark winter months than during the lighter
summer months, an experience known as seasonal affective disorder (SAD), and exposure to
bright lights can help reduce this depression (McGinnis, 2007). [1]
Sleep is also influenced by ambient light. The ganglion cells in the retina send signals to a brain
area above the thalamus called the suprachiasmatic nucleus, which is the body’s primary
circadian ―pacemaker.‖ The suprachiasmatic nucleus analyzes the strength and duration of the
light stimulus and sends signals to the pineal gland when the ambient light level is low or its
duration is short. In response, the pineal gland secretes melatonin, a powerful hormone that
facilitates the onset of sleep.
Research Focus: Circadian Rhythms Influence the Use of Stereotypes in Social Judgments
The circadian rhythm influences our energy levels such that we have more energy at some times of day than others.
Galen Bodenhausen (1990) [2]
argued that people may be more likely to rely on their stereotypes (i.e., their beliefs
about the characteristics of social groups) as a shortcut to making social judgments when they are tired than when
they have more energy. To test this hypothesis, he asked 189 research participants to consider cases of alleged
misbehavior by other college students and to judge the probability of the accused students’ guilt. The accused
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students were identified as members of particular social groups, and they were accused of committing offenses that
were consistent with stereotypes of these groups.
One case involved a student athlete accused of cheating on an exam, one case involved a Hispanic student who
allegedly physically attacked his roommate, and a third case involved an African American student who had been
accused of selling illegal drugs. Each of these offenses had been judged via pretesting in the same student population
to be stereotypically (although, of course, unfairly) associated with each social group. The research participants were
also provided with some specific evidence about the case that made it ambiguous whether the person had actually
committed the crime, and then asked to indicate the likelihood of the student’s guilt on an 11-point scale (0 =
extremely unlikely to 10 = extremely likely).
Participants also completed a measure designed to assess their circadian rhythms—whether they were more active
and alert in the morning (Morning types) or in the evening (Evening types). The participants were then tested at
experimental sessions held either in the morning (9 a.m.) or in the evening (8 p.m.). As you can see in Figure 5.2
"Circadian Rhythms and Stereotyping", the participants were more likely to rely on their negative stereotypes of the
person they were judging at the time of day in which they reported being less active and alert. Morning people used
their stereotypes more when they were tested in the evening, and evening people used their stereotypes more when
they were tested in the morning.
Sleep Stages: Moving Through the Night
Although we lose consciousness as we sleep, the brain nevertheless remains active. The patterns
of sleep have been tracked in thousands of research participants who have spent nights sleeping
in research labs while their brain waves were recorded by monitors, such as
an electroencephalogram, or EEG(Figure 5.3 "Sleep Labs").
Sleep researchers have found that sleeping people undergo a fairly consistent pattern of sleep
stages, each lasting about 90 minutes. As you can see in Figure 5.4 "Stages of Sleep", these
stages are of two major types: Rapid eye movement (REM) sleep is a sleep stage characterized
by the presence of quick fast eye movements and dreaming. REM sleep accounts for about 25%
of our total sleep time. During REM sleep, our awareness of external events is dramatically
reduced, and consciousness is dominated primarily by internally generated images and a lack of
overt thinking (Hobson, 2004). [3]
During this sleep stage our muscles shut down, and this is
probably a good thing as it protects us from hurting ourselves or trying to act out the scenes that
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are playing in our dreams. The second major sleep type, non-rapid eye movement (non-
REM) sleep is a deep sleep, characterized by very slow brain waves, that is further subdivided
into three stages: N1, N2, and N3. Each of the sleep stages has its own distinct pattern of brain
activity (Dement & Kleitman, 1957). [4]
Figure 5.4 Stages of Sleep
6
During a typical night, our sleep cycles move between REM and non-REM sleep, with each cycle repeating at about
90-minute intervals. The deeper non-REM sleep stages usually occur earlier in the night.
As you can see in Figure 5.5 "EEG Recordings of Brain Patterns During Sleep", the brain waves
that are recorded by an EEG as we sleep show that the brain’s activity changes during each stage
of sleeping. When we are awake, our brain activity is characterized by the presence of very
fast beta waves. When we first begin to fall asleep, the waves get longer (alpha waves), and as
we move into stage N1 sleep, which is characterized by the experience of drowsiness, the brain
begins to produce even slower theta waves. During stage N1 sleep, some muscle tone is lost, as
well as most awareness of the environment. Some people may experience sudden jerks or
twitches and even vivid hallucinations during this initial stage of sleep.
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Figure 5.5 EEG Recordings of Brain Patterns During Sleep
Each stage of sleep has its own distinct pattern of brain activity.
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Normally, if we are allowed to keep sleeping, we will move from stage N1 to stage N2 sleep.
During stage N2, muscular activity is further decreased and conscious awareness of the
environment is lost. This stage typically represents about half of the total sleep time in normal
adults. Stage N2 sleep is characterized by theta waves interspersed with bursts of rapid brain
activity known as sleep spindles.
Stage N3, also known as slow wave sleep, is the deepest level of sleep, characterized by an
increased proportion of very slow delta waves. This is the stage in which most sleep
abnormalities, such as sleepwalking, sleeptalking, nightmares, and bed-wetting occur. The
sleepwalking murders committed by Mr. Parks would have occurred in this stage. Some skeletal
muscle tone remains, making it possible for affected individuals to rise from their beds and
engage in sometimes very complex behaviors, but consciousness is distant. Even in the deepest
sleep, however, we are still aware of the external world. If smoke enters the room or if we hear
the cry of a baby we are likely to react, even though we are sound asleep. These occurrences
again demonstrate the extent to which we process information outside consciousness.
After falling initially into a very deep sleep, the brain begins to become more active again, and
we normally move into the first period of REM sleep about 90 minutes after falling asleep. REM
sleep is accompanied by an increase in heart rate, facial twitches, and the repeated rapid eye
movements that give this stage its name. People who are awakened during REM sleep almost
always report that they were dreaming, while those awakened in other stages of sleep report
dreams much less often. REM sleep is also emotional sleep. Activity in the limbic system,
including the amygdala, is increased during REM sleep, and the genitals become aroused, even if
the content of the dreams we are having is not sexual. A typical 25-year-old man may have an
erection nearly half of the night, and the common ―morning erection‖ is left over from the last
REM period before waking.
Normally we will go through several cycles of REM and non-REM sleep each night (Figure 5.5
"EEG Recordings of Brain Patterns During Sleep"). The length of the REM portion of the cycle
tends to increase through the night, from about 5 to 10 minutes early in the night to 15 to 20
minutes shortly before awakening in the morning. Dreams also tend to become more elaborate
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and vivid as the night goes on. Eventually, as the sleep cycle finishes, the brain resumes its faster
alpha and beta waves and we awake, normally refreshed.
Sleep Disorders: Problems in Sleeping
According to a recent poll (National Sleep Foundation, 2009), [5]
about one-fourth of American
adults say they get a good night’s sleep only a few nights a month or less. These people are
suffering from a sleep disorder known asinsomnia, defined as persistent difficulty falling or
staying asleep. Most cases of insomnia are temporary, lasting from a few days to several weeks,
but in some cases insomnia can last for years.
Insomnia can result from physical disorders such as pain due to injury or illness, or from
psychological problems such as stress, financial worries, or relationship difficulties. Changes in
sleep patterns, such as jet lag, changes in work shift, or even the movement to or from daylight
savings time can produce insomnia. Sometimes the sleep that the insomniac does get is disturbed
and nonrestorative, and the lack of quality sleep produces impairment of functioning during the
day. Ironically, the problem may be compounded by people’s anxiety over insomnia itself: Their
fear of being unable to sleep may wind up keeping them awake. Some people may also develop a
conditioned anxiety to the bedroom or the bed.
People who have difficulty sleeping may turn to drugs to help them sleep. Barbiturates,
benzodiazepines, and other sedatives are frequently marketed and prescribed as sleep aids, but
they may interrupt the natural stages of the sleep cycle, and in the end are likely to do more harm
than good. In some cases they may also promote dependence. Most practitioners of sleep
medicine today recommend making environmental and scheduling changes first, followed by
therapy for underlying problems, with pharmacological remedies used only as a last resort.
According to the National Sleep Foundation, some steps that can be used to combat insomnia
include the following:
Use the bed and bedroom for sleep and sex only. Do not spend time in bed during the
day.
Establish a regular bedtime routine and a regular sleep-wake schedule.
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Think positively about your sleeping—try not to get anxious just because you are losing a
little sleep.
Do not eat or drink too much close to bedtime.
Create a sleep-promoting environment that is dark, cool, and comfortable.
Avoid disturbing noises—consider a bedside fan or white-noise machine to block out
disturbing sounds.
Consume less or no caffeine, particularly late in the day.
Avoid alcohol and nicotine, especially close to bedtime.
Exercise, but not within 3 hours before bedtime.
Avoid naps, particularly in the late afternoon or evening.
Keep a sleep diary to identify your sleep habits and patterns that you can share with your
doctor.
Another common sleep problem is sleep apnea, a sleep disorder characterized by pauses in
breathing that last at least 10 seconds during sleep(Morgenthaler, Kagramanov, Hanak, &
Decker, 2006). [6]
In addition to preventing restorative sleep, sleep apnea can also cause high
blood pressure and may raise the risk of stroke and heart attack (Yaggi et al., 2005). [7]
Most sleep apnea is caused by an obstruction of the walls of the throat that occurs when we fall
asleep. It is most common in obese or older individuals who have lost muscle tone and is
particularly common in men. Sleep apnea caused by obstructions is usually treated with an air
machine that uses a mask to create a continuous pressure that prevents the airway from
collapsing, or with mouthpieces that keep the airway open. If all other treatments have failed,
sleep apnea may be treated with surgery to open the airway.
Narcolepsy is a disorder characterized by extreme daytime sleepiness with frequent episodes of
“nodding off.” The syndrome may also be accompanied by attacks of cataplexy, in which the
individual loses muscle tone, resulting in a partial or complete collapse. It is estimated that at
least 200,000 Americans suffer from narcolepsy, although only about a quarter of these people
have been diagnosed (National Heart, Lung, and Blood Institute, 2008). [8]
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Narcolepsy is in part the result of genetics—people who suffer from the disease lack
neurotransmitters that are important in keeping us alert (Taheri, Zeitzer, & Mignot, 2002) [9]
—
and is also the result of a lack of deep sleep. While most people descend through the sequence of
sleep stages, then move back up to REM sleep soon after falling asleep, narcolepsy sufferers
move directly into REM and undergo numerous awakenings during the night, often preventing
them from getting good sleep.
Narcolepsy can be treated with stimulants, such as amphetamines, to counteract the daytime
sleepiness, or with antidepressants to treat a presumed underlying depression. However, since
these drugs further disrupt already-abnormal sleep cycles, these approaches may, in the long run,
make the problem worse. Many sufferers find relief by taking a number of planned short naps
during the day, and some individuals may find it easier to work in jobs that allow them to sleep
during the day and work at night.
Other sleep disorders occur when cognitive or motor processes that should be turned off or
reduced in magnitude during sleep operate at higher than normal levels (Mahowald & Schenck,
2000). [10]
One example is somnamulism(sleepwalking), in which the person leaves the bed and
moves around while still asleep. Sleepwalking is more common in childhood, with the most
frequent occurrences around the age of 12 years. About 4% of adults experience somnambulism
(Mahowald & Schenck, 2000). [11]
Sleep terrors is a disruptive sleep disorder, most frequently experienced in childhood, that may
involve loud screams and intense panic. The sufferer cannot wake from sleep even though he or
she is trying to. In extreme cases, sleep terrors may result in bodily harm or property damage as
the sufferer moves about abruptly. Up to 3% of adults suffer from sleep terrors, which typically
occur in sleep stage N3 (Mahowald & Schenck, 2000). [12]
Other sleep disorders include bruxism, in which the sufferer grinds his teeth during
sleep; restless legs syndrome, in which the sufferer reports an itching, burning, or otherwise
uncomfortable feeling in his legs, usually exacerbated when resting or asleep; and periodic limb
movement disorder, which involves sudden involuntary movement of limbs. The latter can cause
sleep disruption and injury for both the sufferer and bed partner.
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Although many sleep disorders occur during non-REM sleep, REM sleep behavior
disorder (Mahowald & Schenck, 2005) [13]
is a condition in which people (usually middle-aged
or older men) engage in vigorous and bizarre physical activities during REM sleep in response to
intense, violent dreams. As their actions may injure themselves or their sleeping partners, this
disorder, thought to be neurological in nature, is normally treated with hypnosis and medications.
The Heavy Costs of Not Sleeping
Our preferred sleep times and our sleep requirements vary throughout our life cycle. Newborns
tend to sleep between 16 and 18 hours per day, preschoolers tend to sleep between 10 and 12
hours per day, school-aged children and teenagers usually prefer at least 9 hours of sleep per
night, and most adults say that they require 7 to 8 hours per night (Mercer, Merritt, & Cowell,
1998; National Sleep Foundation, 2008). [14]
There are also individual differences in need for
sleep. Some people do quite well with fewer than 6 hours of sleep per night, whereas others need
9 hours or more. The most recent study by the National Sleep Foundation suggests that adults
should get between 7 and 9 hours of sleep per night (Figure 5.8 "Average Hours of Required
Sleep per Night"), and yet Americans now average fewer than 7 hours.
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Figure 5.8 Average Hours of Required Sleep per Night
The average U.S. adult reported getting only 6.7 hours of sleep per night, which is less than the recommended range
propose by the National Sleep Foundation.
Source: Adapted from National Sleep Foundation. (2008). Sleep in America Poll. Washington, DC: Author.
Retrieved fromhttp://www.sleepfoundation.org/sites/default/files/2008%20POLL%20SOF.PDF.
Getting needed rest is difficult in part because school and work schedules still follow the early-
to-rise timetable that was set years ago. We tend to stay up late to enjoy activities in the evening
but then are forced to get up early to go to work or school. The situation is particularly bad for
college students, who are likely to combine a heavy academic schedule with an active social life
and who may, in some cases, also work. Getting enough sleep is a luxury that many of us seem
to be unable or unwilling to afford, and yet sleeping is one of the most important things we can
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do for ourselves. Continued over time, a nightly deficit of even only 1 or 2 hours can have a
substantial impact on mood and performance.
Sleep has a vital restorative function, and a prolonged lack of sleep results in increased anxiety,
diminished performance, and, if severe and extended, may even result in death. Many road
accidents involve sleep deprivation, and people who are sleep deprived show decrements in
driving performance similar to those who have ingested alcohol (Hack, Choi, Vijayapalan,
Davies, & Stradling, 2001; Williamson & Feyer, 2000). [15]
Poor treatment by doctors (Smith-
Coggins, Rosekind, Hurd, & Buccino, 1994) [16]
and a variety of industrial accidents have also
been traced in part to the effects of sleep deprivation.
Good sleep is also important to our health and longevity. It is no surprise that we sleep more
when we are sick, because sleep works to fight infection. Sleep deprivation suppresses immune
responses that fight off infection, and can lead to obesity, hypertension, and memory impairment
(Ferrie et al., 2007; Kushida, 2005). [17]
Sleeping well can even save our lives. Dew et al.
(2003) [18]
found that older adults who had better sleep patterns also lived longer.
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Figure 5.9 The Effects of Sleep Deprivation
In 1964, 17-year-old high school student Randy Gardner remained awake for 264 hours (11 days) in order to set a new Guinness
World Record. At the request of his worried parents, he was monitored by a U.S. Navy psychiatrist, Lt. Cmdr. John J. Ross. This
chart maps the progression of his behavioral changes over the 11 days.
Source: Adapted from Ross, J. J. (1965). Neurological findings after prolonged sleep deprivation. Archives of Neurology, 12, 399–
403.
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Dreams and Dreaming
Dreams are the succession of images, thoughts, sounds, and emotions that passes through our
minds while sleeping. When people are awakened from REM sleep, they normally report that
they have been dreaming, suggesting that people normally dream several times a night but that
most dreams are forgotten on awakening (Dement, 1997). [19]
The content of our dreams
generally relates to our everyday experiences and concerns, and frequently our fears and failures
(Cartwright, Agargun, Kirkby, & Friedman, 2006; Domhoff, Meyer-Gomes, & Schredl,
2005). [20]
Many cultures regard dreams as having great significance for the dreamer, either by revealing
something important about the dreamer’s present circumstances or predicting his future. The
Austrian psychologist Sigmund Freud (1913/1988) [21]
analyzed the dreams of his patients to help
him understand their unconscious needs and desires, and psychotherapists still make use of this
technique today. Freud believed that the primary function of dreams was wish fulfillment, or the
idea that dreaming allows us to act out the desires that we must repress during the day. He
differentiated between the manifest content of the dream (i.e., its literal actions) and its latent
content (i.e., the hidden psychological meaning of the dream). Freud believed that the real
meaning of dreams is often suppressed by the unconscious mind in order to protect the individual
from thoughts and feelings that are hard to cope with. By uncovering the real meaning of dreams
through psychoanalysis, Freud believed that people could better understand their problems and
resolve the issues that create difficulties in their lives.
Although Freud and others have focused on the meaning of dreams, other theories about the
causes of dreams are less concerned with their content. One possibility is that we dream
primarily to help with consolidation, or the moving of information into long-term memory
(Alvarenga et al., 2008; Zhang (2004). [22]
Rauchs, Desgranges, Foret, and Eustache
(2005) [23]
found that rats that had been deprived of REM sleep after learning a new task were
less able to perform the task again later than were rats that had been allowed to dream, and these
differences were greater on tasks that involved learning unusual information or developing new
behaviors. Payne and Nadel (2004) [24]
argued that the content of dreams is the result of
consolidation—we dream about the things that are being moved into long-term memory. Thus
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dreaming may be an important part of the learning that we do while sleeping (Hobson, Pace-
Schott, and Stickgold, 2000). [25]
The activation-synthesis theory of dreaming (Hobson & McCarley, 1977; Hobson,
2004) [26]
proposes still another explanation for dreaming—namely, that dreams are our brain’s
interpretation of the random firing of neurons in the brain stem. According to this approach, the
signals from the brain stem are sent to the cortex, just as they are when we are awake, but
because the pathways from the cortex to skeletal muscles are disconnected during REM sleep,
the cortex does not know how to interpret the signals. As a result, the cortex strings the messages
together into the coherent stories we experience as dreams.
Although researchers are still trying to determine the exact causes of dreaming, one thing
remains clear—we need to dream. If we are deprived of REM sleep, we quickly become less able
to engage in the important tasks of everyday life, until we are finally able to dream again.
K E Y T A K E A W A Y S
Consciousness, our subjective awareness of ourselves and our environment, is functional because it allows us to plan
activities and monitor our goals.
Psychologists believe the consciousness is the result of neural activity in the brain.
Human and animal behavior is influenced by biological rhythms, including annual, monthly, and circadian rhythms.
Sleep consists of two major stages: REM and non-REM sleep. Non-REM sleep has three substages, known as stage N1,
N2, and N3.
Each sleep stage is marked by a specific pattern of biological responses and brain wave patterns.
Sleep is essential for adequate functioning during the day. Sleep disorders, including insomnia, sleep apnea, and
narcolepsy, may make it hard for us to sleep well.
Dreams occur primarily during REM sleep. Some theories of dreaming, such Freud’s, are based on the content of the
dreams. Other theories of dreaming propose that dreaming is related to memory consolidation. The activation-
synthesis theory of dreaming is based only on neural activity.
E X E R C I S E S A N D C R I T I C A L T H I N K I N G
1. If you happen to be home alone one night, try this exercise: At nightfall, leave the lights and any other powered
equipment off. Does this influence what time you go to sleep as opposed to your normal sleep time?
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2. Review your own sleep patterns. Are you getting enough sleep? What makes you think so?
3. Review some of the dreams that you have had recently. Consider how each of the theories of dreaming we have
discussed would explain your dreams.
[1] McGinniss, P. (2007). Seasonal affective disorder (SAD)—Treatment and drugs. Mayo Clinic. Retrieved
from http://www.mayoclinic.com/health/seasonal-affective-disorder/DS00195/DSECTION=treatments%2Dand%2Ddrugs
[2] Bodenhausen, G. V. (1990). Stereotypes as judgmental heuristics: Evidence of circadian variations in
discrimination. Psychological Science, 1, 319–322.
[3] Hobson, A. (2004). A model for madness? Dream consciousness: Our understanding of the neurobiology of sleep offers
insight into abnormalities in the waking brain. Nature, 430, 69–95.
[4] Dement, W., & Kleitman, N. (1957). Cyclic variations in EEG during sleep.Electroencephalography & Clinical Neurophysiology,
9, 673–690.
[5] National Sleep Foundation. (2009). Sleep in America Poll. Washington, DC: Author. Retrieved
fromhttp://www.sleepfoundation.org/sites/default/files/2009%20Sleep%20in%20America%20SOF%20EMBARGOED.pdf
[6] Morgenthaler, T. I., Kagramanov, V., Hanak, V., & Decker, P. A. (2006). Complex sleep apnea syndrome: Is it a unique clinical
syndrome? Sleep, 29(9), 1203–1209. Retrieved from http://www.journalsleep.org/ViewAbstract.aspx?pid=26630
[7] Yaggi, H. K., Concato, J., Kernan, W. N., Lichtman, J. H., Brass, L. M., & Mohsenin, V. (2005). Obstructive sleep apnea as a risk
factor for stroke and death. The New England Journal of Medicine, 353(19), 2034–2041. doi:10.1056/NEJMoa043104
[8] National Heart, Lung, and Blood Institute. (2008). Who is at risk for narcolepsy? Retrieved
from http://www.nhlbi.nih.gov/health/dci/Diseases/nar/nar_who.html
[9] Taheri, S., Zeitzer, J. M., & Mignot, E. (2002). The role of hypocretins (Orexins) in sleep regulation and narcolepsy. Annual
Review of Neuroscience, 25, 283–313.
[10] Mahowald, M., & Schenck, C. (2000). REM sleep parasomnias. Principles and Practice of Sleep Medicine, 724–741.
[11] Mahowald, M., & Schenck, C. (2000). REM sleep parasomnias. Principles and Practice of Sleep Medicine, 724–741.
[12] Mahowald, M., & Schenck, C. (2000). REM sleep parasomnias. Principles and Practice of Sleep Medicine, 724–741.
[13] Mahowald, M., & Schenck, C. (2005). REM sleep behavior disorder. Handbook of Clinical Neurophysiology, 6, 245–253.
[14] Mercer, P., Merritt, S., & Cowell, J. (1998). Differences in reported sleep need among adolescents. Journal of Adolescent
Health, 23(5), 259–263; National Sleep Foundation. (2008). Sleep in America Poll. Washington, DC: Author. Retrieved
fromhttp://www.sleepfoundation.org/sites/default/files/2008%20POLL%20SOF.PDF
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[15] Hack, M. A., Choi, S. J., Vijayapalan, P., Davies, R. J. O., & Stradling, J. R. S. (2001). Comparison of the effects of sleep
deprivation, alcohol and obstructive sleep apnoea (OSA) on simulated steering performance. Respiratory medicine, 95(7), 594–
601; Williamson, A., & Feyer, A. (2000). Moderate sleep deprivation produces impairments in cognitive and motor performance
equivalent to legally prescribed levels of alcohol intoxication. Occupational and Environmental Medicine, 57(10), 649.
[16] Smith-Coggins, R., Rosekind, M. R., Hurd, S., & Buccino, K. R. (1994). Relationship of day versus night sleep to physician
performance and mood. Annals of Emergency Medicine, 24(5), 928–934.
[17] Ferrie, J. E., Shipley, M. J., Cappuccio, F. P., Brunner, E., Miller, M. A., Kumari, M., & Marmot, M. G. (2007). A prospective
study of change in sleep duration: Associations with mortality in the Whitehall II cohort. Sleep, 30(12), 1659; Kushida, C.
(2005). Sleep deprivation: basic science, physiology, and behavior. London, England: Informa Healthcare.
[18] Dew, M. A., Hoch, C. C., Buysse, D. J., Monk, T. H., Begley, A. E., Houck, P. R.,…Reynolds, C. F., III. (2003). Healthy older
adults’ sleep predicts all-cause mortality at 4 to 19 years of follow-up. Psychosomatic Medicine, 65(1), 63–73.
[19] Dement, W. (1997) What all undergraduates should know about how their sleeping lives affect their waking lives. Sleepless
at Stanford. Retrieved fromhttp://www.Stanford.edu/~dement/sleepless.html
[20] Cartwright, R., Agargun, M., Kirkby, J., & Friedman, J. (2006). Relation of dreams to waking concerns. Psychiatry Research,
141(3), 261–270; Domhoff, G. W., Meyer-Gomes, K., & Schredl, M. (2005). Dreams as the expression of conceptions and
concerns: A comparison of German and American college students. Imagination, Cognition and Personality, 25(3), 269–282.
[21] Freud, S., & Classics of Medicine Library. (1988). The interpretation of dreams (Special ed.). Birmingham, AL: The Classics of
Medicine Library. (Original work published 1913)
[22] Alvarenga, T. A., Patti, C. L., Andersen, M. L., Silva, R. H., Calzavara, M. B., Lopez, G.B.,…Tufik, S. (2008). Paradoxical sleep
deprivation impairs acquisition, consolidation and retrieval of a discriminative avoidance task in rats. Neurobiology of Learning
and Memory, 90, 624–632; Zhang, J. (2004). Memory process and the function of sleep. Journal of Theoretics, 6(6), 1–7.
[23] Rauchs, G., Desgranges, B., Foret, J., & Eustache, F. (2005). The relationships between memory systems and sleep
stages. Journal of Sleep Research, 14, 123–140.
[24] Payne, J., & Nadel, L. (2004). Sleep, dreams, and memory consolidation: The role of the stress hormone cortisol. Learning &
Memory, 11(6), 671.
[25] Hobson, J. A., Pace-Schott, E. F., & Stickgold, R. (2000). Dreaming and the brain: Toward a cognitive neuroscience of
conscious states. Behavioral and Brain Sciences, 23(6), 793–842, 904–1018, 1083–1121.
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[26] Hobson, J. A., & McCarley, R. (1977). The brain as a dream state generator: An activation-synthesis hypothesis of the dream
process. American Journal of Psychiatry, 134, 1335–1348; Hobson, J. A. (2004). Dreams Freud never had: A new mind
science. New York, NY: Pi Press.
5.2 Altering Consciousness With Psychoactive Drugs L E A R N I N G O B J E C T I V E S
1. Summarize the major psychoactive drugs and their influences on consciousness and behavior.
2. Review the evidence regarding the dangers of recreational drugs.
A psychoactive drug is a chemical that changes our states of consciousness, and particularly our
perceptions and moods. These drugs are commonly found in everyday foods and beverages,
including chocolate, coffee, and soft drinks, as well as in alcohol and in over-the-counter drugs,
such as aspirin, Tylenol, and cold and cough medication. Psychoactive drugs are also frequently
prescribed as sleeping pills, tranquilizers, and antianxiety medications, and they may be taken,
illegally, for recreational purposes. As you can see in Table 5.1 "Psychoactive Drugs by Class",
the four primary classes of psychoactive drugs are stimulants, depressants, opioids,
and hallucinogens.
Psychoactive drugs affect consciousness by influencing how neurotransmitters operate at the
synapses of the central nervous system (CNS). Some psychoactive drugs are agonists, which
mimic the operation of a neurotransmitter; some are antagonists, which block the action of a
neurotransmitter; and some work by blocking the reuptake of neurotransmitters at the synapse.
Table 5.1 Psychoactive Drugs by Class
Mechanism Symptoms Drug
Dangers and side
effects
Psychological
dependence
Physical
dependence
Addiction
potential
Addiction
potential
Stimulants
Stimulants block the
reuptake of dopamine,
norepinephrine, and
serotonin in the
synapses of the CNS.
Enhanced mood
and increased
energy
Caffeine
May create
dependence Low Low Low
Nicotine
Has major
negative health
effects if smoked High High High
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Mechanism Symptoms Drug
Dangers and side
effects
Psychological
dependence
Physical
dependence
Addiction
potential
Addiction
potential
or chewed
Cocaine
Decreased
appetite, headache Low Low Moderate
Amphetamines
Possible
dependence,
accompanied by
severe ―crash‖
with depression as
drug effects wear
off, particularly if
smoked or injected Moderate Low
Moderate
to high
Depressants
Depressants change
consciousness by
increasing the
production of the
neurotransmitter GABA
and decreasing the
production of the
neurotransmitter
acetylcholine, usually at
the level of the thalamus
and the reticular
formation.
Calming effects,
sleep, pain relief,
slowed heart rate
and respiration
Alcohol
Impaired
judgment, loss of
coordination,
dizziness, nausea,
and eventually a
loss of
consciousness Moderate Moderate Moderate
Barbiturates and
benzodiazepines
Sluggishness,
slowed speech,
drowsiness, in
severe cases, coma
or death Moderate Moderate Moderate
Toxic inhalants
Brain damage and
death High High High
Opioids
The chemical makeup of
opioids is similar to the
endorphins, the
neurotransmitters that
serve as the body’s
―natural pain reducers.‖
Slowing of many
body functions,
constipation,
respiratory and
cardiac
depression, and
the rapid
development of
tolerance
Opium
Side effects
include nausea,
vomiting,
tolerance, and
addiction. Moderate Moderate Moderate
Morphine
Restlessness,
irritability,
headache and body
aches, tremors, High Moderate Moderate
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Mechanism Symptoms Drug
Dangers and side
effects
Psychological
dependence
Physical
dependence
Addiction
potential
Addiction
potential
nausea, vomiting,
and severe
abdominal pain
Heroin
All side effects of
morphine but
about twice as
addictive as
morphine High Moderate High
Hallucinogens
The chemical
compositions of the
hallucinogens are
similar to the
neurotransmitters
serotonin and
epinephrine, and they
act primarily by
mimicking them.
Altered
consciousness;
hallucinations
Marijuana
Mild intoxication;
enhanced
perception Low Low Low
LSD, mescaline,
PCP, and peyote
Hallucinations;
enhanced
perception Low Low Low
In some cases the effects of psychoactive drugs mimic other naturally occurring states of
consciousness. For instance, sleeping pills are prescribed to create drowsiness, and
benzodiazepines are prescribed to create a state of relaxation. In other cases psychoactive drugs
are taken for recreational purposes with the goal of creating states of consciousness that are
pleasurable or that help us escape our normal consciousness.
The use of psychoactive drugs, and especially those that are used illegally, has the potential to
create very negative side effects (Table 5.1 "Psychoactive Drugs by Class"). This does not mean
that all drugs are dangerous, but rather that all drugs can be dangerous, particularly if they are
used regularly over long periods of time. Psychoactive drugs create negative effects not so much
through their initial use but through the continued use, accompanied by increasing doses, that
ultimately may lead to drug abuse.
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The problem is that many drugs create tolerance: an increase in the dose required to produce the
same effect, which makes it necessary for the user to increase the dosage or the number of times
per day that the drug is taken. As the use of the drug increases, the user may develop
a dependence, defined as a need to use a drug or other substance regularly. Dependence can be
psychological, in which the drug is desired and has become part of the everyday life of the user,
but no serious physical effects result if the drug is not obtained; or physical, in which serious
physical and mental effects appear when the drug is withdrawn. Cigarette smokers who try to
quit, for example, experience physical withdrawal symptoms, such as becoming tired and
irritable, as well as extreme psychological cravings to enjoy a cigarette in particular situations,
such as after a meal or when they are with friends.
Users may wish to stop using the drug, but when they reduce their dosage they
experience withdrawal—negative experiences that accompany reducing or stopping drug use,
including physical pain and other symptoms. When the user powerfully craves the drug and is
driven to seek it out, over and over again, no matter what the physical, social, financial, and
legal cost, we say that he or she has developed an addiction to the drug.
It is a common belief that addiction is an overwhelming, irresistibly powerful force, and that
withdrawal from drugs is always an unbearably painful experience. But the reality is more
complicated and in many cases less extreme. For one, even drugs that we do not generally think
of as being addictive, such as caffeine, nicotine, and alcohol, can be very difficult to quit using,
at least for some people. On the other hand, drugs that are normally associated with addiction,
including amphetamines, cocaine, and heroin, do not immediately create addiction in their users.
Even for a highly addictive drug like cocaine, only about 15% of users become addicted
(Robinson & Berridge, 2003; Wagner & Anthony, 2002). [1]
Furthermore, the rate of addiction is
lower for those who are taking drugs for medical reasons than for those who are using drugs
recreationally. Patients who have become physically dependent on morphine administered during
the course of medical treatment for a painful injury or disease are able to be rapidly weaned off
the drug afterward, without becoming addicts. Robins, Davis, and Goodwin (1974) [2]
found that
the majority of soldiers who had become addicted to morphine while overseas were quickly able
to stop using after returning home.
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This does not mean that using recreational drugs is not dangerous. For people who do become
addicted to drugs, the success rate of recovery is low. These drugs are generally illegal and carry
with them potential criminal consequences if one is caught and arrested. Drugs that are smoked
may produce throat and lung cancers and other problems. Snorting (―sniffing‖) drugs can lead to
a loss of the sense of smell, nosebleeds, difficulty in swallowing, hoarseness, and chronic runny
nose. Injecting drugs intravenously carries with it the risk of contracting infections such as
hepatitis and HIV. Furthermore, the quality and contents of illegal drugs are generally unknown,
and the doses can vary substantially from purchase to purchase. The drugs may also contain toxic
chemicals.
Another problem is the unintended consequences of combining drugs, which can produce serious
side effects. Combining drugs is dangerous because their combined effects on the CNS can
increase dramatically and can lead to accidental or even deliberate overdoses. For instance,
ingesting alcohol or benzodiazepines along with the usual dose of heroin is a frequent cause of
overdose deaths in opiate addicts, and combining alcohol and cocaine can have a dangerous
impact on the cardiovascular system (McCance-Katz, Kosten, & Jatlow, 1998). [3]
Although all recreational drugs are dangerous, some can be more deadly than others. One way to
determine how dangerous recreational drugs are is to calculate a safety ratio, based on the dose
that is likely to be fatal divided by the normal dose needed to feel the effects of the drug. Drugs
with lower ratios are more dangerous because the difference between the normal and the lethal
dose is small. For instance, heroin has a safety ratio of 6 because the average fatal dose is only 6
times greater than the average effective dose. On the other hand, marijuana has a safety ratio of
1,000. This is not to say that smoking marijuana cannot be deadly, but it is much less likely to be
deadly than is heroin. The safety ratios of common recreational drugs are shown in Table 5.2
"Popular Recreational Drugs and Their Safety Ratios".
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Table 5.2 Popular Recreational Drugs and Their Safety Ratios
Drug Description Street or brand names
Safety
ratio
Heroin Strong depressant Smack, junk, H 6
GHB (Gamma hydroxy
butyrate)
―Rave‖ drug (not Ecstacy), also
used as a ―date rape‖ drug.
Georgia home boy, liquid ecstasy, liquid
X, liquid G, fantasy 8
Isobutyl nitrite Depressant and toxic inhalant Poppers, rush, locker room 8
Alcohol Active compound is ethanol
10
DXM (Dextromethorphan)
Active ingredient in over-the-
counter cold and cough medicines
10
Methamphetamine May be injected or smoked Meth, crank 10
Cocaine May be inhaled or smoked Crack, coke, rock, blue 15
MDMA (methylene-
dioxymethamphetamine) Very powerful stimulant Ecstasy 16
Codeine Depressant
20
Methadone Opioid
20
Mescaline Hallucinogen
24
Benzodiazepine Prescription tranquilizer
Centrax, Dalmane, Doral, Halcion,
Librium, ProSom, Restoril, Xanax,
Valium 30
Ketamine Prescription anesthetic Ketanest, Ketaset, Ketalar 40
DMT (Dimethyltryptamine) Hallucinogen
50
Phenobarbital
Usually prescribed as a sleeping
pill
Luminal (Phenobarbital), Mebaraland,
Nembutal, Seconal, Sombulex 50
Prozac Antidepressant
100
Nitrous oxide
Often inhaled from whipped cream
dispensers Laughing gas 150
Lysergic acid diethylamide
(LSD)
Acid 1,000
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Drug Description Street or brand names
Safety
ratio
Marijuana (Cannabis) Active ingredient is THC Pot, spliff, weed 1,000
Drugs with lower safety ratios have a greater risk of brain damage and death.
Source: Gable, R. (2004). Comparison of acute lethal toxicity of commonly abused psychoactive substances. Addiction, 99(6),
686–696.
Speeding Up the Brain With Stimulants: Caffeine, Nicotine, Cocaine, and
Amphetamines
A stimulant is a psychoactive drug that operates by blocking the reuptake of dopamine,
norepinephrine, and serotonin in the synapses of the CNS. Because more of these
neurotransmitters remain active in the brain, the result is an increase in the activity of the
sympathetic division of the autonomic nervous system (ANS). Effects of stimulants include
increased heart and breathing rates, pupil dilation, and increases in blood sugar accompanied by
decreases in appetite. For these reasons, stimulants are frequently used to help people stay awake
and to control weight.
Used in moderation, some stimulants may increase alertness, but used in an irresponsible fashion
they can quickly create dependency. A major problem is the ―crash‖ that results when the drug
loses its effectiveness and the activity of the neurotransmitters returns to normal. The withdrawal
from stimulants can create profound depression and lead to an intense desire to repeat the high.
Caffeine is a bitter psychoactive drug found in the beans, leaves, and fruits of plants, where it
acts as a natural pesticide. It is found in a wide variety of products, including coffee, tea, soft
drinks, candy, and desserts. In North America, more than 80% of adults consume caffeine daily
(Lovett, 2005). [4]
Caffeine acts as a mood enhancer and provides energy. Although the U.S. Food
and Drug Administration lists caffeine as a safe food substance, it has at least some
characteristics of dependence. People who reduce their caffeine intake often report being
irritable, restless, and drowsy, as well as experiencing strong headaches, and these withdrawal
symptoms may last up to a week. Most experts feel that using small amounts of caffeine during
pregnancy is safe, but larger amounts of caffeine can be harmful to the fetus (U.S. Food and
Drug Administration, 2007). [5]
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Nicotine is a psychoactive drug found in the nightshade family of plants, where it acts as a
natural pesticide. Nicotine is the main cause for the dependence-forming properties of tobacco
use, and tobacco use is a major health threat. Nicotine creates both psychological and physical
addiction, and it is one of the hardest addictions to break. Nicotine content in cigarettes has
slowly increased over the years, making quitting smoking more and more difficult. Nicotine is
also found in smokeless (chewing) tobacco.
People who want to quit smoking sometimes use other drugs to help them. For instance, the
prescription drug Chantix acts as an antagonist, binding to nicotine receptors in the synapse,
which prevents users from receiving the normal stimulant effect when they smoke. At the same
time, the drug also releases dopamine, the reward neurotransmitter. In this way Chantix dampens
nicotine withdrawal symptoms and cravings. In many cases people are able to get past the
physical dependence, allowing them to quit smoking at least temporarily. In the long run,
however, the psychological enjoyment of smoking may lead to relapse.
Cocaine is an addictive drug obtained from the leaves of the coca plant. In the late 19th and
early 20th centuries, it was a primary constituent in many popular tonics and elixirs and,
although it was removed in 1905, was one of the original ingredients in Coca-Cola. Today
cocaine is taken illegally as recreational drug.
Cocaine has a variety of adverse effects on the body. It constricts blood vessels, dilates pupils,
and increases body temperature, heart rate, and blood pressure. It can cause headaches,
abdominal pain, and nausea. Since cocaine also tends to decrease appetite, chronic users may
also become malnourished. The intensity and duration of cocaine’s effects, which include
increased energy and reduced fatigue, depend on how the drug is taken. The faster the drug is
absorbed into the bloodstream and delivered to the brain, the more intense the high. Injecting or
smoking cocaine produces a faster, stronger high than snorting it. However, the faster the drug is
absorbed, the faster the effects subside. The high from snorting cocaine may last 30 minutes,
whereas the high from smoking ―crack‖ cocaine may last only 10 minutes. In order to sustain the
high, the user must administer the drug again, which may lead to frequent use, often in higher
doses, over a short period of time (National Institute on Drug Abuse, 2009). [6]
Cocaine has a
safety ratio of 15, making it a very dangerous recreational drug.
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Amphetamine is a stimulant that produces increased wakefulness and focus, along with
decreased fatigue and appetite. Amphetamine is used in prescription medications to treat
attention deficit disorder (ADD) and narcolepsy, and to control appetite. Some brand names of
amphetamines are Adderall, Benzedrine, Dexedrine, and Vyvanse. But amphetamine (―speed‖) is
also used illegally as a recreational drug. The methylated version of
amphetamine, methamphetamine (―meth‖ or ―crank‖), is currently favored by users, partly
because it is available in ampoules ready for use by injection (Csaky & Barnes, 1984). [7]
Meth is
a highly dangerous drug with a safety ratio of only 10.
Amphetamines may produce a very high level of tolerance, leading users to increase their intake,
often in ―jolts‖ taken every half hour or so. Although the level of physical dependency is small,
amphetamines may produce very strong psychological dependence, effectively amounting to
addiction. Continued use of stimulants may result in severe psychological depression. The effects
of the stimulant methylenedioxymethamphetamine (MDMA), also known as ―Ecstasy,‖ provide
a good example. MDMA is a very strong stimulant that very successfully prevents the reuptake
of serotonin, dopamine, and norepinephrine. It is so effective that when used repeatedly it can
seriously deplete the amount of neurotransmitters available in the brain, producing a catastrophic
mental and physical ―crash‖ resulting in serious, long-lasting depression. MDMA also affects the
temperature-regulating mechanisms of the brain, so in high doses, and especially when combined
with vigorous physical activity like dancing, it can cause the body to become so drastically
overheated that users can literally ―burn up‖ and die from hyperthermia and dehydration.
Slowing Down the Brain With Depressants: Alcohol, Barbiturates and
Benzodiazepines, and Toxic Inhalants
In contrast to stimulants, which work to increase neural activity, a depressantacts to slow down
consciousness. A depressant is a psychoactive drug that reduces the activity of the CNS.
Depressants are widely used as prescription medicines to relieve pain, to lower heart rate and
respiration, and as anticonvulsants. Depressants change consciousness by increasing the
production of the neurotransmitter GABA and decreasing the production of the neurotransmitter
acetylcholine, usually at the level of the thalamus and the reticular formation. The outcome of
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depressant use (similar to the effects of sleep) is a reduction in the transmission of impulses from
the lower brain to the cortex (Csaky & Barnes, 1984). [8]
The most commonly used of the depressants is alcohol, a colorless liquid, produced by the
fermentation of sugar or starch, that is the intoxicating agent in fermented drinks. Alcohol is the
oldest and most widely used drug of abuse in the world. In low to moderate doses, alcohol first
acts to remove social inhibitions by slowing activity in the sympathetic nervous system. In
higher doses, alcohol acts on the cerebellum to interfere with coordination and balance,
producing the staggering gait of drunkenness. At high blood levels, further CNS depression leads
to dizziness, nausea, and eventually a loss of consciousness. High enough blood levels such as
those produced by ―guzzling‖ large amounts of hard liquor at parties can be fatal. Alcohol is not
a ―safe‖ drug by any means—its safety ratio is only 10.
Alcohol use is highly costly to societies because so many people abuse alcohol and because
judgment after drinking can be substantially impaired. It is estimated that almost half of
automobile fatalities are caused by alcohol use, and excessive alcohol consumption is involved in
a majority of violent crimes, including rape and murder (Abbey, Ross, McDuffie, & McAuslan,
1996). [9]
Alcohol increases the likelihood that people will respond aggressively to provocations
(Bushman, 1993, 1997; Graham, Osgood, Wells, & Stockwell, 2006). [10]
Even people who are
not normally aggressive may react with aggression when they are intoxicated. Alcohol use also
leads to rioting, unprotected sex, and other negative outcomes.
Alcohol increases aggression in part because it reduces the ability of the person who has
consumed it to inhibit his or her aggression (Steele & Southwick, 1985). [11]
When people are
intoxicated, they become more self-focused and less aware of the social situation. As a result,
they become less likely to notice the social constraints that normally prevent them from engaging
aggressively, and are less likely to use those social constraints to guide them. For instance, we
might normally notice the presence of a police officer or other people around us, which would
remind us that being aggressive is not appropriate. But when we are drunk, we are less likely to
be so aware. The narrowing of attention that occurs when we are intoxicated also prevents us
from being cognizant of the negative outcomes of our aggression. When we are sober, we realize
that being aggressive may produce retaliation, as well as cause a host of other problems, but we
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are less likely to realize these potential consequences when we have been drinking (Bushman &
Cooper, 1990). [12]
Alcohol also influences aggression through expectations. If we expect that
alcohol will make us more aggressive, then we tend to become more aggressive when we drink.
Barbiturates are depressants that are commonly prescribed as sleeping pills and painkillers.
Brand names include Luminal (Phenobarbital), Mebaraland, Nembutal, Seconal, and Sombulex.
In small to moderate doses, barbiturates produce relaxation and sleepiness, but in higher doses
symptoms may include sluggishness, difficulty in thinking, slowness of speech, drowsiness,
faulty judgment, and eventually coma or even death (Medline Plus, 2008). [13]
Related to barbiturates, benzodiazepines are a family of depressants used to treat anxiety,
insomnia, seizures, and muscle spasms. In low doses, they produce mild sedation and relieve
anxiety; in high doses, they induce sleep. In the United States, benzodiazepines are among the
most widely prescribed medications that affect the CNS. Brand names include Centrax,
Dalmane, Doral, Halcion, Librium, ProSom, Restoril, Xanax, and Valium.
Toxic inhalants are also frequently abused as depressants. These drugs are easily accessible as
the vapors of glue, gasoline, propane, hair spray, and spray paint, and are inhaled to create a
change in consciousness. Related drugs are the nitrites (amyl and butyl nitrite; ―poppers,‖ ―rush,‖
―locker room‖) and anesthetics such as nitrous oxide (laughing gas) and ether. Inhalants are
some of the most dangerous recreational drugs, with a safety index below 10, and their continued
use may lead to permanent brain damage.
Opioids: Opium, Morphine, Heroin, and Codeine
Opioids are chemicals that increase activity in opioid receptor neurons in the brain and in the
digestive system, producing euphoria, analgesia, slower breathing, and constipation. Their
chemical makeup is similar to the endorphins, the neurotransmitters that serve as the body’s
―natural pain reducers.‖ Natural opioids are derived from the opium poppy, which is widespread
in Eurasia, but they can also be created synthetically.
Opium is the dried juice of the unripe seed capsule of the opium poppy. It may be the oldest drug
on record, known to the Sumerians before 4000 BC.Morphine and heroin are stronger, more
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addictive drugs derived from opium, while codeine is a weaker analgesic and less addictive
member of the opiate family. When morphine was first refined from opium in the early 19th
century, it was touted as a cure for opium addiction, but it didn’t take long to discover that it was
actually more addicting than raw opium. When heroin was produced a few decades later, it was
also initially thought to be a more potent, less addictive painkiller but was soon found to be much
more addictive than morphine. Heroin is about twice as addictive as morphine, and creates
severe tolerance, moderate physical dependence, and severe psychological dependence. The
danger of heroin is demonstrated in the fact that it has the lowest safety ratio (6) of all the drugs
listed in Table 5.1 "Psychoactive Drugs by Class".
The opioids activate the sympathetic division of the ANS, causing blood pressure and heart rate
to increase, often to dangerous levels that can lead to heart attack or stroke. At the same time the
drugs also influence the parasympathetic division, leading to constipation and other negative side
effects. Symptoms of opioid withdrawal include diarrhea, insomnia, restlessness, irritability, and
vomiting, all accompanied by a strong craving for the drug. The powerful psychological
dependence of the opioids and the severe effects of withdrawal make it very difficult for
morphine and heroin abusers to quit using. In addition, because many users take these drugs
intravenously and share contaminated needles, they run a very high risk of being infected with
diseases. Opioid addicts suffer a high rate of infections such as HIV, pericarditis (an infection of
the membrane around the heart), and hepatitis B, any of which can be fatal.
Hallucinogens: Cannabis, Mescaline, and LSD
The drugs that produce the most extreme alteration of consciousness are
the hallucinogens,psychoactive drugs that alter sensation and perception and that may create
hallucinations. The hallucinogens are frequently known as ―psychedelics.‖ Drugs in this class
include lysergic acid diethylamide (LSD, or ―Acid‖), mescaline, and phencyclidine (PCP), as
well as a number of natural plants including cannabis (marijuana), peyote, and psilocybin. The
chemical compositions of the hallucinogens are similar to the neurotransmitters serotonin and
epinephrine, and they act primarily as agonists by mimicking the action of serotonin at the
synapses. The hallucinogens may produce striking changes in perception through one or more of
the senses. The precise effects a user experiences are a function not only of the drug itself, but
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also of the user’s preexisting mental state and expectations of the drug experience. In large part,
the user tends to get out of the experience what he or she brings to it.The hallucinations that may
be experienced when taking these drugs are strikingly different from everyday experience and
frequently are more similar to dreams than to everyday consciousness.
Cannabis (marijuana) is the most widely used hallucinogen. Until it was banned in the United
States under the Marijuana Tax Act of 1938, it was widely used for medical purposes. In recent
years, cannabis has again been frequently prescribed for the treatment of pain and nausea,
particularly in cancer sufferers, as well as for a wide variety of other physical and psychological
disorders (Ben Amar, 2006). [14]
While medical marijuana is now legal in several American
states, it is still banned under federal law, putting those states in conflict with the federal
government. Marijuana also acts as a stimulant, producing giggling, laughing, and mild
intoxication. It acts to enhance perception of sights, sounds, and smells, and may produce a
sensation of time slowing down. It is much less likely to lead to antisocial acts than that other
popular intoxicant, alcohol, and it is also the one psychedelic drug whose use has not declined in
recent years (National Institute on Drug Abuse, 2009). [15]
Although the hallucinogens are powerful drugs that produce striking ―mind-altering‖ effects,
they do not produce physiological or psychological tolerance or dependence. While they are not
addictive and pose little physical threat to the body, their use is not advisable in any situation in
which the user needs to be alert and attentive, exercise focused awareness or good judgment, or
demonstrate normal mental functioning, such as driving a car, studying, or operating machinery.
Why We Use Psychoactive Drugs
People have used, and often abused, psychoactive drugs for thousands of years. Perhaps this
should not be surprising, because many people find using drugs to be fun and enjoyable. Even
when we know the potential costs of using drugs, we may engage in them anyway because the
pleasures of using the drugs are occurring right now, whereas the potential costs are abstract and
occur in the future.
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Research Focus: Risk Tolerance Predicts Cigarette Use
Because drug and alcohol abuse is a behavior that has such important negative consequences for so many people,
researchers have tried to understand what leads people to use drugs. Carl Lejuez and his colleagues (Lejuez, Aklin,
Bornovalova, & Moolchan, 2005) [16]
tested the hypothesis that cigarette smoking was related to a desire to take risks.
In their research they compared risk-taking behavior in adolescents who reported having tried a cigarette at least
once with those who reported that they had never tried smoking.
Participants in the research were 125 5th- through 12th-graders attending after-school programs throughout inner-
city neighborhoods in the Washington, DC, metropolitan area. Eighty percent of the adolescents indicated that they
had never tried even a puff of a cigarette, and 20% indicated that they had had at least one puff of a cigarette.
The participants were tested in a laboratory where they completed the Balloon Analogue Risk Task (BART), a
measure of risk taking (Lejuez et al., 2002). [17]
The BART is a computer task in which the participant pumps up a
series of simulated balloons by pressing on a computer key. With each pump the balloon appears bigger on the screen,
and more money accumulates in a temporary “bank account.” However, when a balloon is pumped up too far, the
computer generates a popping sound, the balloon disappears from the screen, and all the money in the temporary
bank is lost. At any point during each balloon trial, the participant can stop pumping up the balloon, click on a button,
transfer all money from the temporary bank to the permanent bank, and begin with a new balloon.
Because the participants do not have precise information about the probability of each balloon exploding, and
because each balloon is programmed to explode after a different number of pumps, the participants have to
determine how much to pump up the balloon. The number of pumps that participants take is used as a measure of
their tolerance for risk. Low-tolerance people tend to make a few pumps and then collect the money, whereas more
risky people pump more times into each balloon.
Supporting the hypothesis that risk tolerance is related to smoking, Lejuez et al. found that the tendency to take risks
was indeed correlated with cigarette use: The participants who indicated that they had puffed on a cigarette had
significantly higher risk-taking scores on the BART than did those who had never tried smoking.
Individual ambitions, expectations, and values also influence drug use. Vaughan, Corbin, and
Fromme (2009) [18]
found that college students who expressed positive academic values and
strong ambitions had less alcohol consumption and alcohol-related problems, and cigarette
smoking has declined more among youth from wealthier and more educated homes than among
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those from lower socioeconomic backgrounds (Johnston, O’Malley, Bachman, & Schulenberg,
2004). [19]
Drug use is in part the result of socialization. Children try drugs when their friends convince
them to do it, and these decisions are based on social norms about the risks and benefits of
various drugs. In the period 1991 to 1997, the percentage of 12th-graders who responded that
they perceived ―great harm in regular marijuana use‖ declined from 79% to 58%, while annual
use of marijuana in this group rose from 24% to 39% (Johnston et al., 2004). [20]
And students
binge drink in part when they see that many other people around them are also binging (Clapp,
Reed, Holmes, Lange, & Voas, 2006). [21]
Figure 5.13 Use of Various Drugs by 12th-Graders in 2005
Despite the fact that young people have experimented with cigarettes, alcohol, and other
dangerous drugs for many generations, it would be better if they did not. All recreational drug
use is associated with at least some risks, and those who begin using drugs earlier are also more
likely to use more dangerous drugs later (Lynskey et al., 2003). [22]
Furthermore, as we will see
in the next section, there are many other enjoyable ways to alter consciousness that are safer.
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K E Y T A K E A W A Y S
Psychoactive drugs are chemicals that change our state of consciousness. They work by influencing neurotransmitters
in the CNS.
Using psychoactive drugs may create tolerance and, when they are no longer used, withdrawal. Addiction may result
from tolerance and the difficulty of withdrawal.
Stimulants, including caffeine, nicotine, and amphetamine, increase neural activity by blocking the reuptake of
dopamine, norepinephrine, and serotonin in the CNS.
Depressants, including, alcohol, barbiturates, and benzodiazepines, decrease consciousness by increasing the
production of the neurotransmitter GABA and decreasing the production of the neurotransmitter acetylcholine.
Opioids, including codeine, opium, morphine and heroin, produce euphoria and analgesia by increasing activity in
opioid receptor neurons.
Hallucinogens, including cannabis, mescaline, and LSD, create an extreme alteration of consciousness as well as the
possibility of hallucinations.
Recreational drug use is influenced by social norms as well as by individual differences. People who are more likely to
take risks are also more likely to use drugs.
E X E R C I S E S A N D C R I T I C A L T H I N K I N G
1. Do people you know use psychoactive drugs? Which ones? Based on what you have learned in this section, why do
you think that they are used, and do you think that their side effects are harmful?
2. Consider the research reported in the research focus on risk and cigarette smoking. What are the potential
implications of the research for drug use? Can you see any weaknesses in the study caused by the fact that the results
are based on correlational analyses?
[1] Robinson, T. E., & Berridge, K. C. (2003). Addiction. Annual Review of Psychology, 54, 25–53; Wagner, F. A., & Anthony, J. C.
(2002). From first drug use to drug dependence: Developmental periods of risk for dependence upon marijuana, cocaine, and
alcohol.Neuropsychopharmacology, 26(4), 479–488.
[2] Robins, L. N., Davis, D. H., & Goodwin, D. W. (1974). Drug use by U.S. Army enlisted men in Vietnam: A follow-up on their
return home. American Journal of Epidemiology, 99, 235–249.
[3] McCance-Katz, E., Kosten, T., & Jatlow, P. (1998). Concurrent use of cocaine and alcohol is more potent and potentially more
toxic than use of either alone—A multiple-dose study 1. Biological Psychiatry, 44(4), 250–259.
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[4] Lovett, R. (2005, September 24). Coffee: The demon drink? New Scientist, 2518. Retrieved
from http://www.newscientist.com/article.ns?id=mg18725181.700
[5] U.S. Food and Drug Administration. (2007). Medicines in my home: Caffeine and your body. Retrieved
fromhttp://www.fda.gov/downloads/Drugs/ResourcesForYou/Consumers/BuyingUsingMedicineSafely/UnderstandingOver-the-
CounterMedicines/UCM205286.pdf
[6] National Institute on Drug Abuse. (2009). Cocaine abuse and addiction. Retrieved
fromhttp://www.nida.nih.gov/researchreports/cocaine/cocaine.html
[7] Csaky, T. Z., & Barnes, B. A. (1984). Cutting’s handbook of pharmacology (7th ed.). East Norwalk, CT: Appleton-Century-
Crofts.
[8] Csaky, T. Z., & Barnes, B. A. (1984). Cutting’s handbook of pharmacology (7th ed.). East Norwalk, CT: Appleton-Century-
Crofts.
[9] Abbey, A., Ross, L. T., McDuffie, D., & McAuslan, P. (1996). Alcohol and dating risk factors for sexual assault among college
women. Psychology of Women Quarterly, 20(1), 147–169.
[10] Bushman, B. J. (1993). Human aggression while under the influence of alcohol and other drugs: An integrative research
review. Current Directions in Psychological Science, 2(5), 148–152; Bushman, B. J. (Ed.). (1997). Effects of alcohol on human
aggression: Validity of proposed explanations. New York, NY: Plenum Press; Graham, K., Osgood, D. W., Wells, S., & Stockwell,
T. (2006). To what extent is intoxication associated with aggression in bars? A multilevel analysis. Journal of Studies on Alcohol,
67(3), 382–390.
[11] Steele, C. M., & Southwick, L. (1985). Alcohol and social behavior: I. The psychology of drunken excess. Journal of
Personality and Social Psychology, 48(1), 18–34.
[12] Bushman, B. J., & Cooper, H. M. (1990). Effects of alcohol on human aggression: An integrative research
review. Psychological Bulletin, 107(3), 341–354.
[13] Medline Plus. (2008). Barbiturate intoxication and overdose. Retrieved
fromhttp://www.nlm.nih.gov/medlineplus/ency/article/000951.htm
[14] Ben Amar, M. (2006). Cannabinoids in medicine: A review of their therapeutic potential. Journal of Ethnopharmacology,
105, 1–25.
[15] National Institute on Drug Abuse. (2009). NIDA InfoFacts: High School and Youth Trends. Retrieved
from http://www.drugabuse.gov/infofacts/HSYouthTrends.html
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[16] Lejuez, C. W., Aklin, W. M., Bornovalova, M. A., & Moolchan, E. T. (2005). Differences in risk-taking propensity across inner-
city adolescent ever- and never-smokers. Nicotine & Tobacco Research, 7(1), 71–79.
[17] Lejuez, C. W., Read, J. P., Kahler, C. W., Richards, J. B., Ramsey, S. E., Stuart, G. L.,…Brown, R. A. (2002). Evaluation of a
behavioral measure of risk taking: The Balloon Analogue Risk Task (BART). Journal of Experimental Psychology: Applied, 8(2),
75–85.
[18] Vaughan, E. L., Corbin, W. R., & Fromme, K. (2009). Academic and social motives and drinking behavior. Psychology of
Addictive Behaviors. 23(4), 564–576.
[19] Johnston, L. D., O’Malley, P. M., Bachman, J. G., & Schulenberg, J. E. (2004). Monitoring the future: National results on
adolescent drug use. Ann Arbor, MI: Institute for Social Research, University of Michigan (conducted for the National Institute
on Drug Abuse, National Institute of Health).
[20] Johnston, L. D., O’Malley, P. M., Bachman, J. G., & Schulenberg, J. E. (2004). Monitoring the future: National results on
adolescent drug use. Ann Arbor, MI: Institute for Social Research, University of Michigan (conducted for the National Institute
on Drug Abuse, National Institute of Health).
[21] Clapp, J., Reed, M., Holmes, M., Lange, J., & Voas, R. (2006). Drunk in public, drunk in private: The relationship between
college students, drinking environments and alcohol consumption. The American Journal of Drug and Alcohol Abuse, 32(2),
275–285.
[22] Lynskey, M. T., Heath, A. C., Bucholz, K. K., Slutske, W. S., Madden, P. A. F., Nelson, E. C.,…Martin, N. G. (2003). Escalation
of drug use in early-onset cannabis users vs co-twin controls. Journal of the American Medical Association, 289(4), 427–433.
5.3 Altering Consciousness Without Drugs L E A R N I N G O B J E C T I V E
1. Review the ways that people may alter consciousness without using drugs.
Although the use of psychoactive drugs can easily and profoundly change our experience of
consciousness, we can also—and often more safely—alter our consciousness without drugs.
These altered states of consciousness are sometimes the result of simple and safe activities, such
as sleeping, watching television, exercising, or working on a task that intrigues us. In this section
we consider the changes in consciousness that occur through hypnosis, sensory deprivation,
and meditation, as well as through other non-drug-induced mechanisms.
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Changing Behavior Through Suggestion: The Power of Hypnosis
Franz Anton Mesmer (1734–1815) was an Austrian doctor who believed that all living bodies
were filled with magnetic energy. In his practice, Mesmer passed magnets over the bodies of his
patients while telling them their physical and psychological problems would disappear. The
patients frequently lapsed into a trancelike state (they were said to be ―mesmerized‖) and
reported feeling better when they awoke (Hammond, 2008). [1]
Although subsequent research testing the effectiveness of Mesmer’s techniques did not find any
long-lasting improvements in his patients, the idea that people’s experiences and behaviors could
be changed through the power of suggestion has remained important in psychology. James Braid,
a Scottish physician, coined the term hypnosis in 1843, basing it on the Greek word
for sleep(Callahan, 1997). [2]
Hypnosis is a trance-like state of consciousness, usually induced by a procedure known as
hypnotic induction, which consists of heightened suggestibility, deep relaxation, and intense
focus(Nash & Barnier, 2008). [3]
Hypnosis became famous in part through its use by Sigmund
Freud in an attempt to make unconscious desires and emotions conscious and thus able to be
considered and confronted (Baker & Nash, 2008). [4]
Because hypnosis is based on the power of suggestion, and because some people are more
suggestible than others, these people are more easily hypnotized. Hilgard (1965) [5]
found that
about 20% of the participants he tested were entirely unsusceptible to hypnosis, whereas about
15% were highly responsive to it. The best participants for hypnosis are people who are willing
or eager to be hypnotized, who are able to focus their attention and block out peripheral
awareness, who are open to new experiences, and who are capable of fantasy (Spiegel,
Greenleaf, & Spiegel, 2005). [6]
People who want to become hypnotized are motivated to be good subjects, to be open to
suggestions by the hypnotist, and to fulfill the role of a hypnotized person as they perceive it
(Spanos, 1991). [7]
The hypnotized state results from a combination of conformity, relaxation,
obedience, and suggestion (Fassler, Lynn, & Knox, 2008). [8]
This does not necessarily indicate
that hypnotized people are ―faking‖ or lying about being hypnotized. Kinnunen, Zamansky, and
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Block (1994) [9]
used measures of skin conductance (which indicates emotional response by
measuring perspiration, and therefore renders it a reliable indicator of deception) to test whether
hypnotized people were lying about having been hypnotized. Their results suggested that almost
90% of their supposedly hypnotized subjects truly believed that they had been hypnotized.
One common misconception about hypnosis is that the hypnotist is able to ―take control‖ of
hypnotized patients and thus can command them to engage in behaviors against their will.
Although hypnotized people are suggestible (Jamieson & Hasegawa, 2007), [10]
they nevertheless
retain awareness and control of their behavior and are able to refuse to comply with the
hypnotist’s suggestions if they so choose (Kirsch & Braffman, 2001). [11]
In fact, people who
have not been hypnotized are often just as suggestible as those who have been (Orne & Evans,
1965). [12]
Another common belief is that hypnotists can lead people to forget the things that happened to
them while they were hypnotized. Hilgard and Cooper (1965) [13]
investigated this question and
found that they could lead people who were very highly susceptible through hypnosis to show at
least some signs of posthypnotic amnesia (e.g., forgetting where they had learned information
that had been told to them while they were under hypnosis), but that this effect was not strong or
common.
Some hypnotists have tried to use hypnosis to help people remember events, such as childhood
experiences or details of crime scenes, that they have forgotten or repressed. The idea is that
some memories have been stored but can no longer be retrieved, and that hypnosis can aid in the
retrieval process. But research finds that this is not successful: People who are hypnotized and
then asked to relive their childhood act like children, but they do not accurately recall the things
that occurred to them in their own childhood (Silverman & Retzlaff, 1986). [14]
Furthermore, the
suggestibility produced through hypnosis may lead people to erroneously recall experiences that
they did not have (Newman & Baumeister, 1996). [15]
Many states and jurisdictions have
therefore banned the use of hypnosis in criminal trials because the ―evidence‖ recovered through
hypnosis is likely to be fabricated and inaccurate.
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Hypnosis is also frequently used to attempt to change unwanted behaviors, such as to reduce
smoking, overeating, and alcohol abuse. The effectiveness of hypnosis in these areas is
controversial, although at least some successes have been reported. Kirsch, Montgomery, and
Sapirstein (1995) [16]
found that that adding hypnosis to other forms of therapies increased the
effectiveness of the treatment, and Elkins and Perfect (2008) [17]
reported that hypnosis was
useful in helping people stop smoking. Hypnosis is also effective in improving the experiences
of patients who are experiencing anxiety disorders, such as PTSD (Cardena, 2000; Montgomery,
David, Winkel, Silverstein, & Bovbjerg, 2002), [18]
and for reducing pain (Montgomery,
DuHamel, & Redd, 2000; Paterson & Jensen, 2003). [19]
Reducing Sensation to Alter Consciousness: Sensory Deprivation
Sensory deprivation is the intentional reduction of stimuli affecting one or more of the five
senses, with the possibility of resulting changes in consciousness. Sensory deprivation is used for
relaxation or meditation purposes, and in physical and mental health-care programs to produce
enjoyable changes in consciousness. But when deprivation is prolonged, it is unpleasant and can
be used as a means of torture.
Although the simplest forms of sensory deprivation require nothing more than a blindfold to
block the person’s sense of sight or earmuffs to block the sense of sound, more complex devices
have also been devised to temporarily cut off the senses of smell, taste, touch, heat, and gravity.
In 1954 John Lilly, a neurophysiologist at the National Institute of Mental Health, developed the
sensory deprivation tank. The tank is filled with water that is the same temperature as the human
body, and salts are added to the water so that the body floats, thus reducing the sense of gravity.
The tank is dark and soundproof, and the person’s sense of smell is blocked by the use of
chemicals in the water, such as chlorine.
The sensory deprivation tank has been used for therapy and relaxation. In a typical session for
alternative healing and meditative purposes, a person may rest in an isolation tank for up to an
hour. Treatment in isolation tanks has been shown to help with a variety of medical issues,
including insomnia and muscle pain (Suedfeld, 1990b; Bood, Sundequist, Kjellgren, Nordström,
& Norlander, 2007; Kjellgren, Sundequist, Norlander, & Archer, 2001), [20]
headaches
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(Wallbaum, Rzewnicki, Steele, & Suedfeld, 1991), [21]
and addictive behaviors such as smoking,
alcoholism, and obesity (Suedfeld, 1990a). [22]
Although relatively short sessions of sensory deprivation can be relaxing and both mentally and
physically beneficial, prolonged sensory deprivation can lead to disorders of perception,
including confusion and hallucinations (Yuksel, Kisa, Avdemin, & Goka, 2004). [23]
It is for this
reason that sensory deprivation is sometimes used as an instrument of torture (Benjamin,
2006). [24]
Meditation
Meditation refers to techniques in which the individual focuses on something specific, such as an
object, a word, or one’s breathing, with the goal of ignoring external distractions, focusing on
one’s internal state, and achieving a state of relaxation and well-being. Followers of various
Eastern religions (Hinduism, Buddhism, and Taoism) use meditation to achieve a higher spiritual
state, and popular forms of meditation in the West, such as yoga, Zen, and Transcendental
Meditation, have originated from these practices. Many meditative techniques are very simple.
You simply need to sit in a comfortable position with your eyes closed and practice deep
breathing. You might want to try it out for yourself (Note 5.43 "Video Clip: Try Meditation").
Video Clip: Try Meditation
Here is a simple meditation exercise you can do in your own home.
Brain imaging studies have indicated that meditation is not only relaxing but can also induce an
altered state of consciousness. Cahn and Polich (2006) [25]
found that experienced meditators in a
meditative state had more prominent alpha and theta waves, and other studies have shown
declines in heart rate, skin conductance, oxygen consumption, and carbon dioxide elimination
during meditation (Dillbeck, Glenn, & Orme-Johnson, 1987; Fenwick, 1987). [26]
These studies
suggest that the action of the sympathetic division of the autonomic nervous system (ANS) is
suppressed during meditation, creating a more relaxed physiological state as the meditator moves
into deeper states of relaxation and consciousness.
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Research has found that regular meditation can mediate the effects of stress and depression, and
promote well-being (Grossman, Niemann, Schmidt, & Walach, 2004; Reibel, Greeson, Brainard,
& Rosenzweig, 2001; Salmon et al., 2004). [27]
Meditation has also been shown to assist in
controlling blood pressure (Barnes, Treiber, & Davis, 2001; Walton et al., 2004). [28]
A study by
Lyubimov (1992) [29]
showed that during meditation, a larger area of the brain was responsive to
sensory stimuli, suggesting that there is greater coordination between the two brain hemispheres
as a result of meditation. Lutz and others (2004) [30]
demonstrated that those who meditate
regularly (as opposed to those who do not) tend to utilize a greater part of their brain and that
their gamma waves are faster and more powerful. And a study of Tibetan Buddhist monks who
meditate daily found that several areas of the brain can be permanently altered by the long-term
practice of meditation (Lutz, Greischar, Rawlings, Ricard, & Davidson, 2004). [31]
It is possible that the positive effects of meditation could also be found by using other methods
of relaxation. Although advocates of meditation claim that meditation enables people to attain a
higher and purer consciousness, perhaps any kind of activity that calms and relaxes the mind,
such as working on crossword puzzles, watching television or movies, or engaging in other
enjoyed behaviors, might be equally effective in creating positive outcomes. Regardless of the
debate, the fact remains that meditation is, at the very least, a worthwhile relaxation strategy.
Psychology in Everyday Life: The Need to Escape Everyday Consciousness
We may use recreational drugs, drink alcohol, overeat, have sex, and gamble for fun, but in some cases these normally
pleasurable behaviors are abused, leading to exceedingly negative consequences for us. We frequently refer to the
abuse of any type of pleasurable behavior as an “addiction,” just as we refer to drug or alcohol addiction.
Roy Baumeister and his colleagues (Baumeister, 1991) [32]
have argued that the desire to avoid thinking about the self
(what they call the “escape from consciousness”) is an essential component of a variety of self-defeating behaviors.
Their approach is based on the idea that consciousness involvesself-awareness, the process of thinking about and
examining the self. Normally we enjoy being self-aware, as we reflect on our relationships with others, our goals, and
our achievements. But if we have a setback or a problem, or if we behave in a way that we determine is inappropriate
or immoral, we may feel stupid, embarrassed, or unlovable. In these cases self-awareness may become burdensome.
And even if nothing particularly bad is happening at the moment, self-awareness may still feel unpleasant because we
have fears about what might happen to us or about mistakes that we might make in the future.
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Baumeister argues that when self-awareness becomes unpleasant, the need to forget about the negative aspects of the
self may become so strong that we turn to altered states of consciousness. Baumeister believes that in these cases we
escape the self by narrowing our focus of attention to a particular action or activity, which prevents us from having to
think about ourselves and the implications of various events for our self-concept.
Baumeister has analyzed a variety of self-defeating behaviors in terms of the desire to escape consciousness. Perhaps
most obvious is suicide—the ultimate self-defeating behavior and the ultimate solution for escaping the negative
aspects of self-consciousness. People who commit suicide are normally depressed and isolated. They feel bad about
themselves, and suicide is a relief from the negative aspects of self-reflection. Suicidal behavior is often preceded by a
period of narrow and rigid cognitive functioning that serves as an escape from the very negative view of the self
brought on by recent setbacks or traumas (Baumeister, 1990). [33]
Alcohol abuse may also accomplish an escape from self-awareness by physically interfering with cognitive
functioning, making it more difficult to recall the aspects of our self-consciousness (Steele & Josephs, 1990). [34]
And
cigarette smoking may appeal to people as a low-level distractor that helps them to escape self-awareness. Heatherton
and Baumeister (1991) [35]
argued that binge eating is another way of escaping from consciousness. Binge eaters,
including those who suffer from bulimia nervosa, have unusually high standards for the self, including success,
achievement, popularity, and body thinness. As a result they find it difficult to live up to these standards. Because
these individuals evaluate themselves according to demanding criteria, they will tend to fall short periodically.
Becoming focused on eating, according to Heatherton and Baumeister, is a way to focus only on one particular activity
and to forget the broader, negative aspects of the self.
The removal of self-awareness has also been depicted as the essential part of the appeal of masochism, in which
people engage in bondage and other aspects of submission. Masochists are frequently tied up using ropes, scarves,
neckties, stockings, handcuffs, and gags, and the outcome is that they no longer feel that they are in control of
themselves, which relieves them from the burdens of the self (Baumeister, 1991). [36]
Newman and Baumeister (1996) [37]
have argued that even the belief that one has been abducted by aliens may be
driven by the need to escape everyday consciousness. Every day at least several hundred (and more likely several
thousand) Americans claim that they are abducted by these aliens, although most of these stories occur after the
individuals have consulted with a psychotherapist or someone else who believes in alien abduction. Again, Baumeister
and his colleagues have found a number of indications that people who believe that they have been abducted may be
using the belief as a way of escaping self-consciousness.
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K E Y T A K E A W A Y S
Hypnosis is a trance-like state of conscious consisting of heightened susceptibility, deep relaxation, and intense focus.
Hypnosis is not useful for helping people remember past events, but it can be used to alleviate anxiety and pain.
Sensory deprivation is the intentional reduction of stimulation to one or more of the senses. It can be used
therapeutically to treat insomnia, muscle tension, and pain.
Meditation refers to a range of techniques that can create relaxation and well-being.
E X E R C I S E S A N D C R I T I C A L T H I N K I N G
1. Do you think that you would be a good candidate for hypnosis? Why or why not?
2. Try the meditation exercise in this section for three consecutive days. Do you feel any different when or after you
meditate?
[1] Hammond, D. C. (2008). Hypnosis as sole anesthesia for major surgeries: Historical & contemporary
perspectives. American Journal of Clinical Hypnosis, 51(2), 101–121.
[2] Callahan, J. (1997). Hypnosis: Trick or treatment? You’d be amazed at what modern doctors are tackling with an
18th century gimmick. Health, 11, 52–55.
[3] Nash, M., & Barnier, A. (2008). The Oxford handbook of hypnosis: Theory, research and practice: New York, NY:
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[4] Baker, E. L., & Nash, M. R. (2008). Psychoanalytic approaches to clinical hypnosis. In M. R. Nash & A. J. Barnier
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[6] Spiegel, H., Greenleaf, M., & Spiegel, D. (2005). Hypnosis. In B. J. Sadock & V. A. Sadock (Eds.), Kaplan &
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hypnosis: Current models and perspectives, New York, NY: Guilford Press.
[8] Fassler, O., Lynn, S. J., Knox, J. (2008). Is hypnotic suggestibility a stable trait?Consciousness and Cognition: An
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[9] Kinnunen, T., Zamansky, H. S., & Block, M. L. (1994). Is the hypnotized subject lying?Journal of Abnormal
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[10] Jamieson, G. A., & Hasegawa, H. (2007). New paradigms of hypnosis research. Hypnosis and conscious states:
The cognitive neuroscience perspective. In G.A. Jamieson (Ed.), Hypnosis and conscious states: The cognitive
neuroscience perspective (pp. 133–144).New York, NY: Oxford University Press.
[11] Kirsch, I., & Braffman, W. (2001). Imaginative suggestibility and hypnotizability.Current Directions in
Psychological Science. 10(2), 57–61.
[12] Orne, M. T., & Evans, F. J. (1965). Social control in the psychological experiment: Antisocial behavior and
hypnosis. Journal of Personality and Social Psychology, 1(3), 189–200.
[13] Hilgard, E. R., & Cooper, L. M. (1965). Spontaneous and suggested posthypnotic amnesia. International Journal
of Clinical and Experimental Hypnosis, 13(4), 261–273.
[14] Silverman, P. S., & Retzlaff, P. D. (1986). Cognitive stage regression through hypnosis: Are earlier cognitive
stages retrievable? International Journal of Clinical and Experimental Hypnosis, 34(3), 192–204.
[15] Newman, L. S., & Baumeister, R. F. (1996). Toward an explanation of the UFO abduction phenomenon:
Hypnotic elaboration, extraterrestrial sadomasochism, and spurious memories. Psychological Inquiry, 7(2), 99–126.
[16] Kirsch, I., Montgomery, G., & Sapirstein, G. (1995). Hypnosis as an adjunct to cognitive-behavioral
psychotherapy: A meta-analysis. Journal of Consulting and Clinical Psychology, 63(2), 214–220.
[17] Elkins, G., & Perfect, M. (2008). Hypnosis for health-compromising behaviors. In M. Nash & A. Barnier
(Eds.), The Oxford handbook of hypnosis: Theory, research and practice(pp. 569–591). New York, NY: Oxford
University Press.
[18] Cardena, E. (2000). Hypnosis in the treatment of trauma: A promising, but not fully supported, efficacious
intervention. International Journal of Clinical Experimental Hypnosis, 48, 225–238; Montgomery, G. H., David, D.,
Winkel, G., Silverstein, J. H., & Bovbjerg, D. H. (2002). The effectiveness of adjunctive hypnosis with surgical
patients: A meta-analysis.Anesthesia and Analgesia, 94(6), 1639–1645.
[19] Montgomery, G. H., DuHamel, K. N., & Redd, W. H. (2000). A meta-analysis of hypnotically induced analgesia:
How effective is hypnosis? International Journal of Clinical and Experimental Hypnosis, 48(2), 138–153; Patterson,
D. R., & Jensen, M. P. (2003). Hypnosis and clinical pain. Psychological Bulletin, 129(4), 495–521.
[20] Suedfeld, P. (1990b). Restricted environmental stimulation techniques in health enhancement and disease
prevention. In K. D. Craig & S. M. Weiss (Eds.), Health enhancement, disease prevention, and early intervention:
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A., Nordström, G., & Norlander, T. (2007). Effects of flotation rest (restricted environmental stimulation technique)
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on stress related muscle pain: Are 33 flotation sessions more effective than 12 sessions? Social Behavior and
Personality, 35(2), 143–156; Kjellgren, A., Sundequist, U., Norlander, T., & Archer, T. (2001). Effects of flotation-
REST on muscle tension pain. Pain Research & Management, 6(4), 181–189.
[21] Wallbaum, A. B., Rzewnicki, R., Steele, H., & Suedfeld, P. (1991). Progressive muscle relaxation and restricted
environmental stimulation therapy for chronic tension headache: A pilot study. International Journal of
Psychosomatics. 38(1–4), 33–39.
[22] Suedfeld, P. (1990a). Restricted environmental stimulation and smoking cessation: A 15-year progress
report. International Journal of the Addictions. 25(8), 861–888.
[23] Yuksel, F. V., Kisa, C, Aydemir, C., & Goka, E. (2004). Sensory deprivation and disorders of perception. The
Canadian Journal of Psychiatry, 49(12), 867–868.
[24] Benjamin, M. (2006). The CIA’s favorite form of torture. Retrieved
fromhttp://www.salon.com/news/feature/2007/06/07/sensory_deprivation/print.html
[25] Cahn, B., & Polich, J. (2006). Meditation states and traits: EEG, ERP, and neuroimaging studies. Psychological
Bulletin, 132, 180–211.
[26] Dillbeck, M. C., Cavanaugh, K. L., Glenn, T., & Orme-Johnson, D. W. (1987). Consciousness as a field: The
Transcendental Meditation and TM-Sidhi program and changes in social indicators. Journal of Mind and Behavior.
8(1), 67–103; Fenwick, P. (1987). Meditation and the EEG. The psychology of meditation. In M.A. West (Ed.), The
psychology of meditation (pp. 104–117). New York, NY: Clarendon Press/Oxford University Press.
[27] Grossman, P., Niemann, L., Schmidt, S., & Walach, H. (2004). Mindfulness-based stress reduction and health
benefits: A meta-analysis. Journal of Psychosomatic Research. 57(1), 35–43; Reibel, D. K., Greeson, J. M., Brainard,
G. C., & Rosenzweig, S. (2001). Mindfulness-based stress reduction and health-related quality of life in a
heterogeneous patient population. General Hospital Psychiatry, 23(4), 183–192; Salmon, P., Sephton, S.,
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[28] Barnes, V. A., Treiber, F., & Davis, H. (2001). Impact of Transcendental Meditation® on cardiovascular function
at rest and during acute stress in adolescents with high normal blood pressure. Journal of Psychosomatic Research,
51(4), 597–605; Walton, K. G., Fields, J. Z., Levitsky, D. K., Harris, D. A., Pugh, N. D., & Schneider, R. H. (2004).
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program. In R. Yehuda & B. McEwen (Eds.), Biobehavioral stress response: Protective and damaging effects (Annals
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[29] Lyubimov, N. N. (1992). Electrophysiological characteristics of sensory processing and mobilization of hidden
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[31] Lutz, A., Greischar, L., Rawlings, N., Ricard, M., & Davidson, R. (2004). Long-term meditators self-induce high-
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[32] Baumeister, R. F. (1991). Escaping the self: Alcoholism, spirituality, masochism, and other flights from the
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[36] Baumeister, R. F. (1991). Escaping the self: Alcoholism, spirituality, masochism, and other flights from the
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[37] Newman, L. S., & Baumeister, R. F. (1996). Toward an explanation of the UFO abduction phenomenon:
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5.4 Chapter Summary
Consciousness is our subjective awareness of ourselves and our environment.
Consciousness is functional because we use it to reason logically, to plan activities, and to
monitor our progress toward the goals we set for ourselves.
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Consciousness has been central to many theories of psychology. Freud’s personality theories
differentiated between the unconscious and the conscious aspects of behavior, and present-day
psychologists distinguish between automatic (unconscious) and controlled (conscious) behaviors
and between implicit (unconscious) and explicit (conscious) cognitive processes.
The French philosopher René Descartes (1596–1650) was a proponent of dualism, the idea that
the mind, a nonmaterial entity, is separate from (although connected to) the physical body. In
contrast to the dualists, psychologists believe the consciousness (and thus the mind) exists in the
brain, not separate from it.
The behavior of organisms is influenced by biological rhythms, including the daily circadian
rhythms that guide the waking and sleeping cycle in many animals.
Sleep researchers have found that sleeping people undergo a fairly consistent pattern of sleep
stages, each lasting about 90 minutes. Each of the sleep stages has its own distinct pattern of
brain activity. Rapid eye movement (REM) accounts for about 25% of our total sleep time,
during which we dream. Non-rapid eye movement (non-REM) sleep is a deep sleep
characterized by very slow brain waves, and is further subdivided into three stages: stages N1,
N2, and N3.
Sleep has a vital restorative function, and a prolonged lack of sleep results in increased anxiety,
diminished performance, and if severe and extended, even death. Sleep deprivation suppresses
immune responses that fight off infection, and can lead to obesity, hypertension, and memory
impairment.
Some people suffer from sleep disorders, including insomnia, sleep apnea, narcolepsy,
sleepwalking, and REM sleep behavior disorder.
Freud believed that the primary function of dreams was wish fulfillment, and he differentiated
between the manifest and latent content of dreams. Other theories of dreaming propose that we
dream primarily to help with consolidation—the moving of information into long-term memory.
The activation-synthesis theory of dreaming proposes that dreams are simply our brain’s
interpretation of the random firing of neurons in the brain stem.
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Psychoactive drugs are chemicals that change our states of consciousness, and particularly our
perceptions and moods. The use (especially in combination) of psychoactive drugs has the
potential to create very negative side effects, including tolerance, dependence, withdrawal
symptoms, and addiction.
Stimulants, including caffeine, nicotine, cocaine, and amphetamine, are psychoactive drugs that
operate by blocking the reuptake of dopamine, norepinephrine, and serotonin in the synapses of
the central nervous system (CNS). Some amphetamines, such as Ecstasy, have very low safety
ratios and thus are highly dangerous.
Depressants, including alcohol, barbiturates, benzodiazepines, and toxic inhalants, reduce the
activity of the CNS. They are widely used as prescription medicines to relieve pain, to lower
heart rate and respiration, and as anticonvulsants. Toxic inhalants are some of the most
dangerous recreational drugs, with a safety index below 10, and their continued use may lead to
permanent brain damage.
Opioids, including opium, morphine, heroin, and codeine, are chemicals that increase activity in
opioid receptor neurons in the brain and in the digestive system, producing euphoria, analgesia,
slower breathing, and constipation.
Hallucinogens, including cannabis, mescaline, and LSD, are psychoactive drugs that alter
sensation and perception and which may create hallucinations.
Even when we know the potential costs of using drugs, we may engage in using them anyway
because the rewards from using the drugs are occurring right now, whereas the potential costs are
abstract and only in the future. And drugs are not the only things we enjoy or can abuse. It is
normal to refer to the abuse of other behaviors, such as gambling, sex, overeating, and even
overworking as ―addictions‖ to describe the overuse of pleasant stimuli.
Hypnosis is a trance-like state of consciousness, usually induced by a procedure known as
hypnotic induction, which consists of heightened suggestibility, deep relaxation, and intense
focus. Hypnosis also is frequently used to attempt to change unwanted behaviors, such as to
reduce smoking, eating, and alcohol abuse.
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Sensory deprivation is the intentional reduction of stimuli affecting one or more of the five
senses, with the possibility of resulting changes in consciousness. Although sensory deprivation
is used for relaxation or meditation purposes and to produce enjoyable changes in consciousness,
when deprivation is prolonged, it is unpleasant and can be used as a means of torture.
Meditation refers to techniques in which the individual focuses on something specific, such as an
object, a word, or one’s breathing, with the goal of ignoring external distractions. Meditation has
a variety of positive health effects.
