Why is a particular child right-handed or left-handed? / by George M. Gould.

  • Gould, George Milbrey, 1848-1922.
Date:
1907
Catalogue details

Licence: In copyright

Credit: Why is a particular child right-handed or left-handed? / by George M. Gould. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    baby of a year of age shows some be- ginnings of the peculiar expertness, but the progress in specialization and in the acquirement of kinds and de- grees of expertness never ceases while life lasts. And there are as many mixes of peculiarities as there are in- dividuals ; there are almost as many anomalous as there are typical cases. As a rule, of course, the hand chosen for the most expert tasks is increas- ingly chosen, and people tend to fall into two great classes, the right- handed and the left-handed. All left- handed mechanics (and now every- body uses machines!) are handicapped and bothered by the fact that all ma- chines, even to screws, are made for the right-handed. Not to be forgotten also is the number, large in the aggre- gate, of the right-handed who, by ac- cident, injury, etc., lose the superior expertenss of the right eye, right hand, right leg or foot; and, converse- ly, the number of the left-handed who suffer similarly as regards their sinis- tral expertness. In such cases there is a transfer of task to the opposite or- gans, and a slow, difficult, and always imperfect expertness is acquired. But in every case there is a crippling, and a lessening of productive capacity, a disadvantaging in the struggle. And more surely is there a mixing from the ground up, or rather from the top of the head down, of hitherto co-ordi- nated and related functions. The cen- ter for the intermediation of an abso- lutely necessary psychic and neurolo- gic datum to the engineered composite act has to be transferred to the op- posite side of the brain. There is, of course, halting, indecision, slowness, or genuine inhibition of function be- cause of the difficulty of correlating the data from the two sides of the brain. Many a case of stuttering, probably most, slowness and morbidi- ties of speech, etc., are due to this di- vision or misplacement of the inner- vating centers in opposed cerebral hemispheres—all bound with right- eyedness, right-handedness, or the op- posites, etc. Think also of the appalling amount of misery, mental and physical, the disease, the shame, that for untold ages has been thrust upon the left- handed by parents, social custom, etc. There is even now scarcely a poor left-handed child who is not cursed by the attempt to make him right-handed. There are about three million naturally left-handed in the United States! Ev- ery one of them, if not absolutely dis- eased, is made morbid, less happy, handicapped, by the peculiarity a little, by the cruelty of changing it a vast deal. Add the millions of millions that must have lived since the first finger of the dextral hand was held up in counting! In savage times the savage mother and father, and tribe, must have horribly maltreated the poor un- fortunates. There is only a little proof of this in the Keep to the Right of our common law, in the wrong and igno- miny associated with the words sinis- ter, gauche, etc., and the honor born of mere contrast, of course, in right, dextrous, dexterity, etc. Focus the converging lines of the argument! The 97 per cent, by all laws of inheritance and of mechanics should long ago have extinguished the relatively few left-handed anomalies. They persist, and perhaps increasing- ly. The mixed types are certainly in- creasing. The vindictive effect of per- secution, shame, and cruelty, united to the number of the mutilated, would add powerfully to exclude them in the long history of human evolution. They reappear as numerously, as mysteri- ously, apparently as illogically as ever, and certainly in mockery of any known law of heredity. Why? To understand the answer it should be remembered that forward move- ment of a four-footed animal, com- posed of two poorly united or co-or- dinated longitudinal halves, must be by means of the governors of all movement—vision. One organ of this vision was for the one badly co-ordi- nated half-body, the other for the op- posite half. The brain was halved, also, but a slow and poor correlating mechanism was begun and is being improved, at present much improved. Even now the right eye is united in function with the right hand, the