Читать книгу The psychology of sleep онлайн

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It frequently happens that, as a man waxes older, he requires less and less sleep than in his growing and most active years. But old people who have outlived their mental life come to a time when they sleep and perform merely the physical functions like the infant; so also with those whose energy so far exceeds their physical strength that the mere effort of living exhausts them. This condition may be in part due to overstrain of the powers of youth and middle age, but it also follows the fixed idea that years diminish strength and lessen energy. It is easy to fall into this notion, for it accords so well with the general idea that rest must come only after the period of activity, whether that period be a day or a lifetime.

All of us have had periods when we have needed fewer than our average hours of sleep. People who sleep out of doors or in thoroughly ventilated rooms, under warm but light clothing, find that they need less sleep than when they occupy poorly ventilated rooms and wrap themselves in heavy, unhygienic clothing. Fresh discoveries are being made almost daily by those who give intelligent consideration to these things.