WHAT IS SLEEP?

Taranaki Daily News, Volume LVII, Issue 120, 14 October 1914, Page 2

WHAT IS SLEEP?

> SOME EXPERIMENTS. Ws ordinarily think that the ood.T can do without everything else better than without food and drink. But experiments on animals have shown that many of them will die more quickly when deprived of sleep than when deprived of food and water. Men have performed all sorts of experiment* to find out the exact nature of sleep. One of them undertook to keep a dog awake a3 long as possible to determine the effect of the loss of sleep on him. There was the problem, however, of keeping him awake without making him tired, for the fatigue might cover up the effect of the mere loss of sleep. It has been found that dogs can stay awake for about ten days, but *t that time the limit of endurance is reached, and nothing that can be done will keep them awake any longer. The temperature of the body remains normal, and the amount of carbon-dioxide—the ashes of the btaod, so to speak—undergoes no increase; this proves that it is not the impoverishment of the blood in oxygen or an over-abundant supply of carbondioxide that causes sleep. Furthermore, neither the blood nor the brain lose their ordinary supply of water, which disposes of the theory that lack of water is Hie cause of sleep. Towards the tenth day a dog that is kept awake can no longer keep its eyes open; its jaws are continually bending, and only the strongest kind of efforts will rouse it. At this moment' the brain colls of the frontal lobe begin to show marked disturbances, but as soon as the dog is allowed to go to sleep these disappear. Is this due to exhaustion or intoxication?

Jn trying to determine that question Legendre took a certain fluid from the brain of a dog that was very sleepy and injected it into the veins of an animal that had just had a good, sound snooxe. The result was that this animal immediate-',}- began to grow drowsy. Little by little it began to blink its eyes and to relax its legs; finally it closed ita eyes, and then went into a deep sleep. Its brain promptly showed all the signs of the same sort of cell disturbances that had ended the wakeful hours of the insomnia-suffering dog. On the other hand, when this brain fluid from a normal dog was injected into the veins of another animal it did not produce any tunduncy to sleep at all.

The result of all these wonderful experiments show that it is possible to transmit the absolute need of Bleep from an exhausted aninul to a normal one. Whether this discovery ever will lead to a method of producing real sleep at will m not known.