At the new place a person sleeps deeply, only one of the hemispheres


from Brown University biologists have discovered that the human brain, sleep in an unfamiliar place for him, is not functioning as normal. The left hemisphere is not fully switched to sleep and, in the words of one researcher, "slightly more" awake than the right.

Back in the 1970s, biologists studying marine mammals found that dolphins in the REM sleep state alternately is only one of the two hemispheres of the brain. It is believed that the reason for this is that dolphins, like other marine mammals, from time to time have to rise to the water surface for breathing.

People do not need to surface to breathe, but each felt on themselves or heard from his friends about the discomfort arising when held in a new location at night. Often people complain that they are tired and not enough sleep. Physiologists "first night effect" has been known since the days when they began to study the sleep of people in laboratories. Results of the first night's sleep simply excluded from consideration, since at this time of sleep is often disturbed.

Yuka Sasaki [Yuka Sasaki], the author of this work, I decided to study in detail what occurs during sleep the first night in a new place, what with his colleagues scanned the brain waves of 35 university students, all favorite experimental scientists.

Scientists interested in brain activity during REM sleep. The slow sleep - is the first thing a person experiences after falling asleep. It consists of four stages. It is believed that REM sleep is associated with a reduction of energy consumption. Studies have shown that it is the phase of slow wave sleep is the key to secure the conscious "declarative" memories. During the slow sleep goes REM sleep, or rapid eye movement stage.

Sasaki and his colleagues found that during the first night in the lab in certain areas of the right hemisphere of the brain activity of slow waves (theta rhythm) was higher than in the corresponding areas of the left hemisphere of the brain. In the following night, this difference disappeared completely.

To confirm the findings of the students put two experiments associated with the sound. First sleep lost monophonic sound that suddenly gave way to a different tone. It is known that the sleeper shallow brain responds to such stimulation. Students also have observed the reaction of the brain - but only the left half

. Then they sleep lost sound louder, able to awaken sleeping man shallow. As a result of waking up only those who lost the sound in the right ear, associated with the left hemisphere of the brain.

Commenting on the work of scientists, Niels Rattenborg [Niels Rattenborg], exploring the dream bird ornithological Max Planck Institute, he said that previously nobody has been able to demonstrate the difference in the hemispheres of the brain during sleep in humans, in particular - the opportunity to rest only one hemisphere
Rattenborg noted that such properties previously attributed only to dolphins, some other marine mammals (fur seals), as well as some birds. He himself was a few years ago was engaged in research of sleep ducks, and found that the number of ducks raised in sleep differently. Those birds that have been on both sides of their tovarki, slept soundly. Extreme also slept only one half of the brain awake while the eye followed the approach of predators.

Although people have long do not have to worry about predators, but an evolutionary instinct designated "the night is dark and full of horror" does not give us rest easy in an unfamiliar environment.



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