“Man should forget his anger before he lies down to sleep” Mahatma Gandhi (1869-1948)

Sleep and Dreams

“Man should forget his anger before he lies down to sleep”
Mahatma Gandhi (1869-1948)

We may not give it a moment's thought, but most of us will probably spend the third of our lives asleep. Yet the nature of sleep has puzzled mankind for thousands of years; it is only in the last quarter (четверть) of a century that researchers have made scientific attempts to investigate this world, trying to find out why some people have enormous difficulty falling asleep, while others find it impossible to stay awake. Far from being a passive state, sleep is a remarkably active one. While the sleeper is outwardly calm, the electrical activity of the brain never stops. As the sleep becomes deeper and deeper, the brain-waves become larger and more spread out.

While the sleeper still thinks thoughts and moves occasionally, the metabolic processes slow down and the heartbeat drops until deep sleep is reached.

Every day every human being experiences two kinds of sleep that alternate rhythmically throughout the entire sleep period. The discovery of the two kinds of sleep occurred almost accidentally at the University of Chicago. In 1952 Dr. Kleitman became interested in the slow rolling eye movements that accompany sleep onset (начало) and decided to look for these eye movements throughout the night to determine whether they were related to the depth or quality of sleep. An entirely new kind of eye movement was noticed at certain times during night, the eyes began to dart (быстро двигаться) about furiously ['fjuariasli] beneath the closed lids(веки).

Dr. Kleitman coined the term "REM" (for Rapid - Eye -Movement sleep) to define the phenomenon he and his collegues observed. The other kind eventually acquired the name "NREM" I'nonrem ] sleep. The "NREM" state is often called "quiet sleep", because of the slow, regular breathing, the general absence of body movement, and the slow, regular brain activity shown in the EEG. The body is not paralyzed during NREM sleep. The first sleep of the night is always NREM sleep, which must progress through its various stages before the first REM period occurs. REM sleep, which has been called "active sleep" is an entirely different state of existence. At the onset of REM sleep the sleeper's body is still immobile, but we can see small, convulsive twitches (подергивания) of his face and fingertips (кончики пальцев)

Experts speculate that REM sleep protects us from acting out our dreams and hurting ourselves, and that it is not really sleep at all, but a state in which the subject is awake, but paralyzed and hallucinating. The sleeper's breathing becomes irregular — very fast, then slow — he may even appear to stop breathing for several seconds. If you gently pull back the eyelids the sleeper seems to be actually looking at something. Cerebral blood flow and brain temperature soar to new heights, but large muscles of the body are completely paralyzed: arms, legs, and trunk cannot move.

The NREM-REM cycle varies from 70 to 110 minutes, but averages around 90 min. In the early part of the night sleep is dominated by the NREM state, but as the night progresses, the periods of quiet sleep become shorter and the REM episodes longer. The first REM period lasts 10 min., but by early morning they can last as long as an hour. So we are believed to go into REM sleep and dream roughly every 90 m, all night long. So most of us sleep in two distinct ways: REM sleep, when we dream, and "quiet" sleep when we simply sleep.

The fact that it is more difficult to awaken a person from REM than from NREM sleep provides some initial support for Freud's idea that dreams protect sleep. An additional partial test of the Freudian theory is to deprive (лишать) subjects of REM sleep, thus depriving them of dreams. If subjects arc-awakened every time there is an onset of REM, they have a night's sleep without dreams. Early experiments indicated that after such deprivation there was more REM sleep the following night, indicating that there is a kind of "quota" for REM; and when there is less REM sleep one night, more will be required the next. Indirectly, this would support the Freudian theory of dreams as a protector of sleep. However, other findings of sleep and dream studies contradict the interpretation of REM as a protector of sleep. In the first place, REM is prominent (заметный) in infants, when meaningful! Dreams are unlikely to occur, and also in lower mammals (млекопитающие). The study of the dreams of older children shows that their dreams reflect the realistic activities of their waking lives and that emotional disturbances occur in their dreams when there are emotional disturbances in their waking lives (Foulkes, 1971).

The only conclusion to be drawn is that the psycho-physiological studies of dreams have given little support to the Freudian theory that the purpose of dreams is to protect sleep.

But from the work done so far, it appears that dreaming serves several cognitive functions: it is measurably involved in mood changes; it seems to provide the energy space for working out problems set aside through days filled with busy activity; and, in general, it offers a kind of workshop for the repair of self-esteem (чувство собственного достоинства) and competence.

Key Words

Transcribe the following words. Mind the stress:

1. to alternate – to occur in turn repeatedly

2. onset – beginning

3. to coin – to invent (a new word or phrase)

4. REM sleep -rapid eye movement sleep

5. NREM sleep: non-rapid eye movement sleep

6. trunk - a person's or animal's body apart from the limbs and head

7. infants - are children between the ages of five and seven, who go to an infant school

8. emotional disturbance – strong feeelings

9. self-esteem - confidence in one's own worth or abilities

10. competence - the ability to do something successfully or efficiently

Answer the following questions to check how carefully you read the text:

1. Is sleep a passive state? Why?

2. How did Dr. Kleitman discover the two kinds of sleep?

3. How did he call the two kinds of sleep?

4. Can you describe the "NREM" state?

5. What is REM sleep itself?

6. How does the NREM-REM cycle function?

7. Have the psycho-physiological studies of dreams given support to the Freudian theory that the purpose of dreams is to protect sleep?

8. What will happen if a person is deprived of dreams?

9. What are the other findings of sleep and dream studies that contradict the interpretation of REM as a protector of sleep?

10. What cognitive functions can dreaming serve?

Now decide whether the following statements are true or false:

1. B

2.

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