Page:Popular Science Monthly Volume 18.djvu/626

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THE POPULAR SCIENCE MONTHLY.

tive sensations responding to nothing external, and symptoms of anæsthesia manifested by an abolition of the perceptions belonging to the affected part. These two classes of symptoms may also alternate in the same disease, as in the motor and intellectual regions.

A characteristic case, confirming this theory, is that of a child who fell on his head and buried a portion of the parietal in the surface of the brain. He became blind in the eye of the opposite side. He was trepanned, and the blindness ceased immediately. Soon inflammation arose at the wounded part; blindness returned and lasted till the inflammation disappeared. Compression of the visual center, first by the bone and then by the products of inflammation, was the evident cause of this intermittent blindness. Other cases establish the possibility of abnormal stimulation of the visual center.

The centers of hearing, taste, odor, and touch are localized in the same way, and, if the observations are not very numerous, they make a strong presumption in favor of the localization actually adopted. It sometimes happens that several centers are affected at the same time. In these cases, if the lesion is an irritating one, there occurs from time to time a simultaneous discharge producing a singular mixture of sensations. One such patient, observed by Ferrier, said that he had the sensation of a horrible odor and green thunder. We admit that the clinical arguments in favor of the localization of the sensitive centers are not so numerous or conclusive as could be wished. But only lately have they been sought, and each day brings its contribution, which, considering the rarity of limited lesions of the brain, can not be very considerable.

The localization of intelligence in the frontal region of the brain was thought of long before our day. Gratiolet used the expression frontal races for intelligent races; and those of least intelligence have been called occipital races. The frontal region is greatest in man along with the predominance of reason and logic, while in women, who are dominated by their sensibilities, the occipital region prevails. We may cite to the same point the researches of Bordier on the skulls of assassins, of Luys on the brains of fools and idiots, of Bénédikt on the brains of criminals, of Lombroso on the characters of habitual criminals. Their conclusions are analogous, and favor more than they oppose the popular idea.

But these arguments are not precise and positive. Happily there are others more scientific and more conclusive. Take the celebrated crowbar case, where a young man, who was blasting, had a pointed bar of iron about three quarters of an inch in diameter and weighing three pounds, driven, by a sudden explosion, upward through his head. It entered at the angle of the under jaw, passed behind the nose and eyes, penetrated the skull, and cutting the cerebral substance of the frontal region passed out at the top of the head, above the forehead and to the right of the median line. The wound was frightful. All one part