HOW THE BRAIN TIRES.

Auckland Star, Volume XXXI, Issue 292, 8 December 1900, Page 2 (Supplement)

HOW THE BRAIN TIRES.

Brain cells, Avhen quite fresh and vigorous, may be likened to small balloons inflated ready for an ascent. They are round and full, and when seen under the microscope they give evidence of being distended. The cells cf the tired brain, on the other hand, , are seen to be shrunken, as an air ball or toy balloon from which most of the air or gas has escaped. When our brains begin to work after a refreshing rest or sleep they are, says "Pearson's Weekly," full of nerve fluid, which the absorbents of the body and brain have stored up there like bees fill their comb. So soon as work begins this vital force is sapped to meet the demands upon the brain, and the process that goes on during the' whole time it is working may be described in the following way:, — Imagine that these cells are small goblets fiilled with liquid, and that they have a tiny stem, through which runs a tube or opening*. The liquid in the goblet is drained by the demands of mind and body and slowly trickles through the opening drop by drop until either the work ceases or the goblet is exhausted. This latter condition is not often reached, for the simple reason that the owner of the brain is very much more likely to collapse. When the cell has yielded half its vital fluid you begin to experience a feeling of fatigue, and if yon g;o on drawing the contents of the cells you are doing yourself injury in a proportionate degree, and nature will make you pay for it in some way or oilier. But all the cells are not involved in any kind of mental work, which means that one part of the brain may be very .actively at work while the other is resting and storing up nerve fluid. This it is that a man suffering from brain fag may leave his books ,and go golfing or cycling and feel that he is really resting. Other cells are being called upon for work now, while the tired ones--tho?e required for mental activity—are enjoying repose. But it follows that the part of the brain which is called into activity for bodily exercise is now getting r.ired, while the other part of the brain is still at work to some extent, and so the whole of our brain cells become fatigued, and total rest in the shape of sleep is absolutely essential.