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commercial truck drivers (National Highway Traffic Safety Administration, 2018).
Drivers are 5 to 10 times more likely to have an accident late at night than during
daytime hours. The reason is easy to find. Monitoring of EEG activity shows that
those who drive in the middle of the night often take quick, 2- to 3-second
microsleeps, which elevates the risk of accident (Al-Lawati, 2018; Kecklund &
Akerstedt, 1993). A study of 80 long-haul truck drivers revealed that 56 percent had
at least one episode of drowsiness and two drifted briefly into a light stage of sleep
(Mitler, Miller, Lipsitz, Walsh, & Wylie, 1997). A study of 35 people in a driving
simulator revealed a slowed heart rate and brain-wave patterns indicative of
drowsiness. Over time, many subjects yawned, blinked quickly, closed their eyes,
nodded off, drifted lanes, and made driving errors resulting in collisions (Lai & Craig,
2002). There are times when a person just can’t avoid the situation. Often when I’m
out of town and have to return for an early-morning class, I’ll find myself driving late at
night and fighting to keep my eyes open. Is there a way to counteract this tendency?
Studies have shown that a brief nap and a cup of coffee will help drivers stay awake
(Al-Lawati, 2018; Horne & Reyner, 1996).
microsleep. A brief episode of sleep that occurs in the midst of a wakeful activity.
To avoid traffic, many truckers drive at night. However, they are more likely to
have an accident during nighttime hours than in the daytime.
Lee Rentz / Alamy Stock Photo
The Stages of Sleep
Just as activity levels follow a rhythm, so too does sleep. Every night, humans
cycle through five distinct stages of sleep. Much of what is known about these stages
first came to light in the 1950s, thanks to the pioneering collaborative work of
Nathaniel Kleitman, Eugene Aserinksy, and William Dement. The scientific study of
sleep is now highly active (American Psychological Association, 2020a; Grandner,
2019; Hobson, 2003).
To appreciate how these discoveries were made, imagine that you’re a subject in
a sleep study. As you enter the sleep lab, you meet an experimenter, who gives you
some questionnaires to fill out, prepares you for the experience, and takes you to a
carpeted, tastefully decorated, soundproof “bedroom.” Electrodes are then taped to
your scalp to record brain-wave activity, near your eyes to measure eye movements,
and under your neck and chin to record muscle tension (illustrated in Figure 4.3).
Other devices may also be used to measure your breathing, heart rate, and even
genital arousal. The pillow is fluffy, the bed is okay, and the blanket is warm. But you
know you’re being watched, and you can feel the electrodes and wires on your skin,
so you wonder how you’ll ever manage to fall asleep. The experimenter reassures
you that it may take a couple of nights to adapt to the situation.
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Description
Figure 4.3 Measuring Sleep
Carolina Hrejsa/Body Scientific Intl.
Presleep
The experimenter departs, shuts off the lights, and leaves you alone. As you try to
settle down, EEG recordings reveal that all is well (illustrated in Figure 4.4). Typical of
a person who is awake and alert, your EEG shows short, quick beta waves. This
pattern indicates that different parts of your brain are producing small bursts of
electrical activity at different times—a sure sign of mental activity. Your eyes move
rapidly up and down and from side to side, and many of your muscles are tensed.
Description
Figure 4.4 The Stages of Sleep
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Stages 1 to 4
You start to become drowsy. Your breathing slows down, your mind stops racing,
your muscles relax, your eyes move less, and EEG recordings show a slower, larger,
and somewhat more regular pattern of alpha waves (alpha waves appear to occur
when people are relaxed but not focused on something specific). For a minute or two,
you drift into a “hypnogogic state” in which you may imagine seeing flashes of color
or light, and perhaps you jerk your leg abruptly as you sense yourself falling. You are
entering stage 1 sleep. Electrical activity in the brain slows down some more, in a
pattern of theta waves. Your breathing becomes more regular, your heart rate slows,
and your blood pressure drops. This is a period of very light sleep. No one makes a
sound or calls your name, however, so you don’t wake up.
After about 10 minutes in stage 1 sleep, your EEG pattern shows waves that are
even slower and larger. As you slip into stage 2 sleep, you become progressively
more relaxed, the rolling eye movements stop, and you become less easily disturbed.
On the EEG, stage 2 is marked by periodic short bursts of activity called sleep
spindles. If the experimenter in the next room makes a noise, your brain will register a
response—but you probably will not wake up. In the laboratory, subjects detect a
change in a tone 95 percent of the time while awake, 47 percent of the time in stage
1 sleep, and only 3 percent of the time in stage 2 sleep (Cote, De Lugt, & Campbell,
2002).
After about 20 minutes in stage 2, you fall into the deepest stages of sleep.
Stages 3 and 4 are hard to distinguish because they differ only in degree. Both are
marked by the onset of very slow waves with large peaks, called delta waves, which
last for about 30 minutes (delta waves seem to indicate that increasing numbers of
neurons are firing together, in synchrony). At this point, you are “out like a light” or
“sleeping like a rock.” If the phone rings, you may not hear it. If you do answer the
call, you’ll sound dazed and confused. It is during the very deep sleep of stages 3
and 4 when young children may wet the bed or when you may walk or talk in your
sleep. It’s this stage that Mark Twain had in mind when he said, “There ain’t no way to
find out why a snorer can’t hear himself snore.” Yet in keeping with the adaptive and
very selective nature of attention, certain noises will penetrate consciousness. New
parents may be oblivious to the sounds of traffic outside, for example, but they’re
quick to hear the baby cry.
REM Sleep
After an hour of deepening sleep, something odd happens—something first
discovered in Kleitman’s lab (Aserinksy & Kleitman, 1953; Dement & Kleitman, 1957;
Kleitman, 1963). Rather than maintain your deep sleep, you begin to cycle backward
to stage 3, then to stage 2. But then instead of returning to stage 1, you enter a new,
fifth stage, marked by two dramatic types of changes. On the one hand, the EEG
reveals a surge of short, high-frequency beta waves like those found when you were
awake. Also indicating an increased level of activity, blood flow to the brain increases,
your breathing and pulse rates speed up, and your genitals become aroused—even
without sexual thoughts or dreams. At the same time, you have lost skeletal muscle
tone throughout the body. In fact, your arms, legs, and trunk are so totally relaxed
that, except for an occasional twitch, you are completely paralyzed. You’re also hard
to awaken at this stage. This odd combination—of being internally active but
externally immobile—has led some researchers to refer to this stage of sleep as
paradoxical.
The most prominent change occurs in the eyes. The eyelids are shut, but
underneath, your eyeballs are darting frantically back and forth as if you were
watching a world-class Ping-Pong match. These rapid eye movements are so
pronounced that this stage has been named REM sleep—and it is contrasted with
stages 1 through 4, which are lumped together as non-REM, or NREM, sleep. What
makes rapid eye movements so special is what they betray about the state of your
mind. When sleeping subjects are awakened during non-REM stages, they report on
dreams about 50 percent of the time. Yet when subjects are awakened during REM,
they report on dreams about 80 percent of the time—and that includes subjects who
came into the lab saying they don’t ever dream (Foulkes, 1962). Clearly, everyone
dreams throughout the night, during both REM and NREM sleep (Squier & Domhoff,
1998). But compared to the fleeting thoughts and images reported during stages 1
through 4, REM dreams are more visual, vivid, detailed, and storylike. In the mind’s
late-night theater, the production of dreams can be seen in the resurgence of activity
within the eyes and brain.
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REM sleep. The rapid-eye-movement stage of sleep associated with dreaming.
NREM sleep. The stages of sleep not accompanied by rapid eye movements.
From the time you fall asleep, it takes about 90 minutes to complete one cycle.
The contrasts within this cycle are striking. Coleman (1986) describes NREM sleep
as “an idling brain in a moveable body” and REM as “an active brain in a paralyzed
body.” In a full night’s sleep, you are likely to recycle through the stages four to six
times. The first time through the cycle, you spend only about 10 minutes in REM
sleep. As the night wears on, however, you spend less time in the deeper NREM
periods and more time in REM sleep. During the last hour before you awaken in the
morning, the REM period is 30 to 60 minutes long. This explains why people are so
often in the middle of a dream when the mechanical tyrant we call an alarm clock
rings. The sleep cycles and the progression of stages within each cycle are illustrated
in Figure 4.5.
Description
Figure 4.5 A Typical Night’s Sleep
Garrett, Brain and Behavior, 5e, 2018, SAGE Publications, Inc
What’s Your Prediction?
How much sleep do we need to function during the day and stay healthy? Clearly,
people differ. Thomas Edison, inventor of the modern light bulb, required only about 4
hours a night. This fact is interesting given that Edison’s 1913 light bulb precipitated a
decline in the amount of sleep people get—from 9 hours a night, measured in 1910,
to... well, you make the call. As part of its Sleep in America poll, the National Sleep
Foundation (2018) asked a random sample of 1,000 adults to identify which of five
items was most important to them personally. What are your predictions? Look at
Figure 4.6, and you’ll find that Americans do not tend to prioritize sleep compared to
other parts of their lives. How much do you prioritize sleep? According to the poll, a
majority of the public (65 percent) says that getting enough sleep makes them a more
effective person, yet 41 percent admit to rarely considering how much sleep they
need in planning for the next day.
Description
Figure 4.6 Sleep Priority Among Americans
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Source: National Sleep Foundation’s 2018 Sleep in America® Poll
Why Do We Sleep?
Because humans spend a third of their lives in this state, it’s natural to wonder:
Why do we sleep? When we are tired, the urge to doze is overwhelming and very
hard to fight, regardless of what we’re doing or where we are. And if we are still tired
when the alarm clock rings, we might shut it off, clutch our pillows to our ears, or just
pretend we didn’t hear it—even if we have a schedule to keep. Our need for sleep is
powerful and irresistible. But why?
One way to investigate this question is to deprive people of sleep and find out
what happens. You may have pulled a few “all-nighters” but probably not for periods
of time that are long enough to push the limits. A unique opportunity to observe the
effects of sleep deprivation presented itself in New York City in 1959. As part of a
fund-raising drive, disc jockey Peter Tripp forced himself to stay awake and on the air
for 200 hours. By the fifth day, Tripp’s speech was slurred, and he was hallucinating
and showing signs of paranoia (he believed that “enemies” were trying to drug his
coffee). It seemed that sleep was essential to his mental health. But after sleeping for
13 hours, Tripp had recovered completely.
A second highly publicized case came about in 1964, when 17-year-old Randy
Gardner sought fame in the Guinness Book of World Records. As part of a high
school science project, and with the help of two friends, Gardner stayed awake for
264 hours—that’s 11 straight days, a world record (which was later broken). When it
was over, he held a news conference, during which he said, “It’s just mind over
matter.” He went to sleep for 14 hours, woke up feeling fine, and resumed his normal
schedule. Follow-up tests initially confirmed that Gardner suffered no long-term ill
effects. For many years, the Gardner story was surrounded by the myth that he
suffered no ill effects during the episode. But daily tests administered to Gardner
showed that his thinking was fragmented, his speech was slurred, he couldn’t
concentrate, he had memory lapses, and toward the end, he was hallucinating. Then,
in later years, Gardner suffered unbearable insomnia and reported being terrified of
going even a single night without sleep (Coren, 1996; National Public Radio, 2017).
On the basis of these episodes and many studies, sleep researchers have
concluded that sleep is a necessary function. There are four types of explanations for
why this is so: restoration, circadian patterns, consolidation, and neural synthesis.
One explanation comes from restoration theory, which states that sleep recharges
the battery, enabling us to recover from the day’s physical, cognitive, and emotional
demands. This theory explains why people feel run-down as the day wears on and
refreshed after a night’s sleep. Restoration is thought to be achieved largely in stages
3 and 4—or deep sleep.
A second explanation for why we sleep comes from the circadian theory, which
focuses on the evolutionary significance of sleep. All animals sleep or undergo
regular intervals of inactivity. According to this view, sleep is a neural mechanism that
has evolved over time so that animals can conserve energy and minimize their
exposure to predators when they are not foraging for food or seeking a mate.
Circadian theory correctly predicts that there are species-specific differences in sleep
patterns. As shown in Figure 4.7, animals that sleep the longest find food easily and
are well hidden from predators while sleeping. In contrast, animals that sleep the
shortest amount of time spend more hours foraging and can defend themselves only
by running away. Seen from this perspective, we humans sleep at night because
we’re not very well adapted to searching for food in the dark or protecting ourselves
from nocturnal predators (Allison & Cicchetti, 1976; Horne, 1988).
Description
Figure 4.7 Daily Hours of Sleep: Cross-Species Comparisons
Monica Wierzbicki/Body Scientific Intl.
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A third explanation comes from theories of consolidation—the process of
converting short-term memory to long-term memory (Peever & Fuller, 2016).
Consolidation occurs in the hippocampus, a region of the brain known to be
associated with memory. This region is highly active during REM sleep, as are other
regions in the brain where memory conversion is evident, to include the motor cortex
(Li, Ma, Yang, & Gan, 2017; Sterpenich et al., 2014). In this way, sleep, particularly
REM sleep, is a time for the brain to “organize” our memories.
A fourth explanation comes from activation-synthesis theory (Antrobus, 1991;
Scarpelli et al., 2021), which explains that sleep functions to allow the synthesis (or
merging) of random neural activity. Neural synthesis is a type of bottom-up
processing in which processing, initiated in the hindbrain, causes activation in the
cortex, leading to dreaming. Specifically, studies show that regions responsible for
processing visual information—but not the visual cortex specifically—are active
during dreaming. During emotional dreams, limbic regions responsible for emotion
(the amygdala) are also highly active (Perogamvros & Schwartz, 2012). Dreaming,
then, is a by-product of this synthesis of random neural activity.
Dreams
Have you ever had a recurring dream? Some 75 percent of Americans report
having recurring dreams; nearly 39 percent started in childhood. What is your
recurring dream about? Maybe that you were falling? Being chased? Flying? Meeting
a celebrity? Or maybe something more serious. . . like finding out a partner is
cheating? Driving in an out-of-control vehicle? Or maybe something more taboo... like
having sex with someone you shouldn’t have? Being naked in public? Or maybe
something more serious. . . like being paralyzed or unable to speak? Experiencing a
death of yourself or a loved one? Or maybe something more off the wall. . . such as
being unable to find a toilet? Going nowhere or moving in slow motion? If any of
these recurring dreams sound familiar, then you are not alone. A recent poll of more
than 2,000 Americans found that these are common recurring dreams (Hyde, 2020).
More than 50 percent of respondents reported dreams about falling or being chased;
nearly 33 percent reported flying; 32 percent, having sex with someone they shouldn’t
have; 30 percent, experiencing a death of themselves or a loved one; 26 percent,
going nowhere or moving in slow motion; 24 percent, being paralyzed or unable to
speak; 18 percent, finding out a partner is cheating; 15 percent, being naked in
public; 14 percent, meeting a celebrity or driving in an out-of-control vehicle; and 13
percent, being unable to find a toilet. Other common dreams included being back in
school (38 percent), being unprepared for a test or an important event (34 percent),
having teeth fall out (27 percent), being lost (27 percent), drowning (9 percent), and
even encountering aliens or UFOs (7 percent). So, what are dreams, why do we have
them, and what, if anything, do they mean?
The Nature of Dreams
Dreams are less puzzling now than they were before the 1953 discovery of REM
sleep. Psychologists used to think that the mind was idling in sleep and that dreaming
was a rare, and therefore significant, event. But then EEG recordings revealed that
the sleeping human brain is active and that everyone dreams, without exception,
several times a night. We now know that dreams are electrochemical events involving
the brainstem and areas of the cortex and that the eyes flutter back and forth. What
more is known about this mysterious state of consciousness, a state in which the
mind is active but the sleeper is immobilized and hard to awaken?
Researchers now believe that REM sleep and the dreaming that often
accompanies it are biologically adaptive. This belief arises from three sources of
evidence. The first is that all mammals have REM sleep (most birds do too, but
reptiles, amphibians, and fish do not)—from a high of 57 percent of all sleep time in
the platypus to a low of 2 percent in the dolphin (Siegel, 2001). Second, the amount
of REM sleep is greatest early in life, while the brain is developing—and there is
evidence to suggest that REM sleep is necessary for brain maturation (Marks,
Shaffrey, Oksenberg, Speciale, & Roffwarg, 1995). Among premature infants, 60 to
80 percent of all sleep time is spent in the REM stage. That proportion drops to 50
percent in full-term newborns, 30 percent in 6-month-olds, 25 percent in 2-year-olds,
and 20 percent in early childhood, before diminishing later in life. Third, when
subjects are deprived of REM sleep one night, they exhibit a “rebound effect” by
taking extra REM time the next night (Brunner, Kijk, Tobler, & Borbely, 1990).
Is there a linkage between a sleeper’s eye movements and dreams? This is a
tricky question. Research shows that the longer a REM episode is, the more words
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an awakened subject uses to describe the dream—and the more elaborate the story.
Similarly, the more active the brain is during REM, the more eventful are the dreams
that are later reported. But patterns of eye movements do not seem to correspond to
the images and actions of a dream—as when we follow characters in a film (Chase &
Morales, 1983).
What Do People Dream About?
What do people dream about? What do you dream about? Over the years,
analyses of dream content have shown that certain themes seem to arise with
remarkable frequency. Can you guess the three most commonly reported dreams?
Figure 4.8 lists many of the most common recurring dreams. The first is of falling. The
second is of being chased or attacked. The third is of being back in school. Also
common are dreams of flying, being unprepared or late for a big event, being
rejected, and interacting with someone who just passed (Hyde, 2020).
Description
Figure 4.8 Most Common Recurring Dreams
Source: Weinstein, N., Campbell, R. & Vansteenkiste, M. Linking
psychological need experiences to daily and recurring dreams. Motiv
Emot 42, 50–63 (2018). https://doi.org/10.1007/s11031-017-9656-0
According to research, we tend to recognize most of the characters in our dreams
with fewer than one-fifth of dream characters being unrecognizable to the dreamer
(Kahn et al., 2008). Other research indicates that our waking lives influence what we
dream. For example, women who are pregnant dream more about childbirth and
musicians dream about music twice and often as non-musicians do (Lara-Carrasco et
al., 2013; Uga et al., 2006). Still, our capacity for dreaming extends beyond our own
experiences. For example, people born paralyzed dream of walking, swimming, and
running as often as those without paralysis, and people born deaf often report that
they hear in their dreams (Voss et al., 2011).
What influences the contents of our dreams? There are two documented sources.
One is the concerns of everyday life. If you’re struggling financially, if you’ve had a
death in the family, or if you’re studying for an important exam or are involved in an
exciting new relationship, these issues may well slip into your dreams (Nikles, Brecht,
Klinger, & Bursell, 1998). External stimuli are a second source of influence. Have you
at a concert? Dement (1992) sprayed water on subjects’ hands during REM sleep,
awakened them a short time later, and found that 42 percent—far more than normal
—reported dreaming of rainfalls, leaking roofs, swimming pools, and the like.
Similarly, 56 percent incorporated into their dreams the taped sounds of dogs, trains,
bells, and other stimuli.
For some dreamers, there is a third source of influence that, in some ways, is the
most interesting: themselves. As a general rule, people are not aware that they are
dreaming while they are dreaming. But have you ever had the odd sensation of
dreaming—and knowing that you were in a dream? This “half in–half out” state of
consciousness is called lucid dreaming. Most people have experienced this state on
only an occasional basis—as when a dream takes on such a bizarre quality that they
know it cannot be real. But some people are frequent lucid dreamers, and it appears
to be a skill that can be developed. In some studies, lucid dreamers were trained to
signal the onset of a dream to an experimenter by moving their eyes and clenching
their fists. Some lucid dreamers say that at times they can control the contents—and
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outcomes—of their own dreams. If true, then perhaps lucid dreaming can be used to
resolve personal conflicts and tame the monsters in our nightmares (LaBerge, 1992;
Rotenberg, 2015).
lucid dreaming. A semiconscious dream state in which sleepers are aware that
they are dreaming.
Our dreams may be influenced by inner concerns and external stimuli and even
by our own will. And most dreams are fairly mundane (Cipolli, Bolzani, Cornoldi,
DeBeni, & Fagioli, 1993). But sometimes our dreams have a bizarre, magical quality
—whereby time seems to stand still or speed forward, shadowy figures appear and
vanish on cue, or we fall into bottomless pits, soar like Superman, and float in utter
defiance of gravity. How can these qualities be explained? And what do they tell us
about why we dream? No one really knows for sure, but there are two major theories.
Presumably, we all dream, whether we recall them or not. Understanding what
dreams we have and why we have them is a focus of interest for many psychologists.
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Freud’s Interpretation
In 1900, Sigmund Freud published a classic book entitled The Interpretation of
Dreams. According to Freud, all people are unconsciously motivated to satisfy sexual
and aggressive urges. These ideas are too threatening to express or even to
recognize, so we keep them from awareness through the use of psychological
defense mechanisms. So far, so good. During sleep, however, our defensive guard is
down, and pent-up drives can no longer be suppressed. It would be psychologically
shattering to come face to face with our deepest, darkest urges. Such realizations
would also disrupt our sleep. The solution: We construct dreams that express the
fulfillment of these drives—but in ways that are too indirect and confusing to
recognize. In short, the dream we remember in the morning is a disguised, scrambled
expression of unconscious wishes. The drive is fulfilled, but in such a way that the
psyche—and our sleep—is protected.
With his theory of psychoanalysis to guide him (refer to Chapter 14), Freud saw
dreams as a “royal road” to the unconscious. He called the dream we remember in
the morning the manifest content. The underlying thoughts, urges, conflicts, and
needs that give rise to that dream constitute its latent content. According to Freud,
the only way to uncover this unconscious latent material (which, after all, is the “true
meaning”) is to decode the dream and the symbols that disguise it. In the language of
dreams, he said, kings and queens symbolize parents; small animals symbolize
children; a house symbolizes the human body; and flying is the mental equivalent of
having sex.
manifest content. According to Freud, the conscious dream content that is
remembered in the morning.
latent content. According to Freud, the unconscious, censored meaning of a
dream.
Activation-Synthesis Theory
Freud’s theory is hard to prove or disprove, and many psychologists worry that it
leads us to “overinterpret” dreams. Recent theories take a more neuropsychological
approach. The most influential is the activation-synthesis theory of J. Allan Hobson
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and Robert McCarley (1977), which was later revised by Hobson (1988). According to
this two-process theory, random neural signals firing in the brainstem spread up to
the cortex (activation). Drawing on past experiences stored in memory, the brain then
creates images and stories in an effort to make sense out of these random signals
(synthesis). According to this account, the brightness, color, and clarity of dream
images are triggered by random bursts of sensory neurons during REM sleep
(Antrobus, 1991; Hobson & Friston, 2012). Similarly, the physical-motion dreams that
Freud described as typical (flying, climbing, falling) are triggered by the activity of
motor neurons during REM sleep (Porte & Hobson, 1996).
activation-synthesis theory. The theory that dreams result from the brain’s
attempt to make sense of random neural signals that fire during sleep.
Comparing Perspectives
Both Freud’s account and activation-synthesis theory agree that the dream’s
manifest content is not meaningful. But they differ in two respects. The first concerns
the interpretation of the manifest content. For Freud, the mind constructs bizarre
dreams to disguise their true meaning from the dreamer. For Hobson, the brain
constructs bizarre dreams because it has only limited information and operates on
short notice. Thus, “the manifest content is the dream. There is no other dream”
(Hobson, 1988, p. 258). The second key difference concerns the significance
attached to the so-called latent content. Freud believed that dreams spring from deep
unconscious wishes. Hobson and McCarley argued that dreams are the incidental byproduct of neural overactivity.
Research continues to enlighten these dual perspectives on dreaming. For
example, Allen Braun and colleagues (1998) used PET scans on sleeping subjects
and found that the limbic regions of the brain—areas that control our motivations and
emotions—were highly active during REM sleep. In contrast, the frontal lobes—
involved in the processes of attention, planning, logical thinking, and short-term
memory—were inactive. These results may help to explain why dreams often seem
bizarre and illogical. They’re also consistent with Freud’s contention that dreams
reflect deep-seated motivations and emotions—something of a “wishing system,” in
the words of neuropsychologist Mark Solms (Carpenter, 1999). At this point, there is
not enough research to declare a winner between these theoretical approaches. In
fact, new theories are still being proposed. Building on the work of Solms (1997),
Foulkes (1999), and Domhoff (2001), Yvette Graveline and Erin Wamsley (2015)
have proposed that dreaming is a natural extension of waking conscious experience.
In this light, dreaming is a cognitive activity that involves a special neural network in
the forebrain that develops through childhood, and the contents of our dreams are not
that different from our waking thoughts, concerns, and feelings. At this point, all that is
clear is that through a complex interplay of physiological and psychological
processes, the mind is remarkably active during sleep.
Sleep Disturbances
At some point in life, nearly everyone suffers from a sleep-related problem. You lie
in bed, tossing and turning, brooding over something that happened or worrying
about something that might. Or you keep nodding off in class, at work, or in other
embarrassing situations. Or you leap up in a cold sweat, with your heart pounding,
from a realistic and terrifying nightmare. In general, there are three types of sleep
disturbances: sleeping too little (insomnia), sleeping too much (hypersomnia), and
having disturbed or troubled sleep (parasomnia).
Insomnia
The sleep disturbance known as insomnia is characterized by a recurring inability
to fall asleep, stay asleep, or get the amount of sleep needed to function during the
day. Very few of us adhere to the daily “ideal” of 8 hours for work, 8 for play, and 8 for
sleep. On the contrary, people differ in the amount of sleep they want. Some are at
their most alert after 6 hours a night, whereas others need 9 or 10 hours to get along.
How much time is sufficient depends on who you are.
insomnia. An inability to fall asleep, stay asleep, or get the amount of sleep
needed to function during the day.
About one-third of the population complains of insomnia—and roughly half of
these people consider the problem to be serious (American Psychiatric Association,
2020). It’s not easy to know when someone has insomnia based on self-report,
however. In a study that illustrates the point, Mary Carskadon brought 122
insomniacs into the laboratory and compared their self-perceptions to EEG measures
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of sleep. The next morning, the subjects estimated that it took them an hour to fall
asleep and that they slept for 4.5 hours. But EEG tracings revealed that it took them
only 15 minutes to fall asleep, which is average, and that they slept for 6.5 hours.
More than 10 percent of all complaints are from “pseudoinsomniacs” who sleep
normally but don’t realize it. Part of the problem is that people with insomnia worry so
much about getting to sleep, and then getting enough sleep, that they monitor
themselves closely and overestimate the extent of the problem (Harvey, 2002;
Neubauer, Pandi-Perumal, Spence, Buttoo, & Monti, 2018).
For many people, getting to sleep and staying asleep can be a challenge,
affecting about a third of the population.
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Today, you can use wearable devices, such as an Apple Watch, a Fitbit, or even a
basic phone app to monitor your own sleep. These devices and apps can track many
characteristics of your sleep, including duration and quality of sleep and how often
you woke up (that is, how often your sleep was interrupted). One caution, though, is
that most evidence shows that sleep trackers on wearable devices and in apps can
only help you identify patterns in your sleep and give you a good “guesstimate” as to
how much sleep you are getting (Evenson, Goto, & Furberg, 2015; Gruwez,
Bruyneel, & Bruyneel, 2019). To know exactly how much sleep you are getting, the
quality of that sleep, and certainly whether or not your sleep is disordered, you’d have
to participate in a medical sleep study or see a physician.
At times, everyone has trouble falling asleep. But what should you do if the
problem persists? Research shows that many people can help themselves simply by
altering their own sleep-related behavior (American Psychiatric Association, 2017;
Maas, 1998). Some recommendations from physicians and psychologists include the
following:
Record how much sleep you get in a night, and set that total as a goal. If you
sleep 4 or 5 hours, aim for a 4-hour schedule.
Do not take naps during the day.
Avoid all alcohol, caffeine, and cigarettes within 5 hours of bedtime; avoid
exercise within 2 hours of bedtime; relax.
Make sure the bedroom is dark, quiet, and comfortable when you go to bed.
That also means not streaming videos or using your phone in bed. When you
awaken, turn on the lights and lift the shades.
Keep a rigid schedule. Get into bed at 1 AM, not earlier. Set the alarm for 5
AM—and get out of bed no matter what.
If you’re awake but relaxed, stay in bed.
If you’re awake and anxious, get out of bed and return when you are sleepy.
Keep the alarm set, and get up when it rings.
If you stick to this schedule, you should see results. If you want, you can then
add 30 to 60 minutes to your schedule.
Rest assured that you can get by on less sleep than you want and that a
temporary loss of sleep will cause you no harm.
Can this advice get you to sleep better on your own, without the help of a
professional? To answer this question, Veronique Mimeault and Charles Morin (1999)
recruited 58 people complaining of insomnia. For a six-week period, one-third of
participants were given a take-home course consisting of treatment booklets on
sleep, insomnia, and the management of sleep problems. For a second group, the
program included weekly phone calls from a therapist. In a third, no-treatment control
group, subjects spent the time waiting for the program to begin. Before and after the
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