Page:Popular Science Monthly Volume 26.djvu/766

This page has been proofread, but needs to be validated.
746
THE POPULAR SCIENCE MONTHLY.

followed by a most violent and rapid whirling of the body, the direction being toward the affected side if the injury extends through the entire lobe, but toward the opposite side if the lesion be partial. Comparing these results of experiments with the teachings of pathology, i. e., with diseases of the cerebellum in man, there is an unexpected disagreement. Changes in one of the lobes may occur without any observable symptoms. It is only when there is a thorough wasting of the lobe that we have marked disturbances, and these are not simply connected with movements, they affect the intelligence as well. This fact has been specially noted by Wundt, who refers to the striking example furnished by Combetti's case of the girl Labrosse. This girl was entirely destitute of cerebellum and pons Varolii and yet was capable of voluntary movements, though showing great muscular weakness and lack of intelligence. Bouillard reports the case of Guérin, whose cerebellum was shown to be almost wholly destroyed, "yet the patient could co-ordinate his movements, even being able to walk." It should be observed that in both these cases there was muscular feebleness, shown by the reeling and tottering motions of the persons diseased. It is customary to mention the ninety-three cases collected Fig. 12.—Human Cerebrum and Cerebellum, showing the relative size of those parts of the Brain. (After Hirschfeld and Léveillé.) by Andral, to show that the cerebellum is not an organ for the co-ordination of movements. Professor Austin Flint, of New York, has made a most careful examination of these cases, and has fully established the fact that none of them, save perhaps two, could possibly be taken to have a bearing on the question. Almost all the cases are complicated with diseases in other brain-masses, or exhibit sufficient disorder of movement to confirm the original position. There is a striking fact, first noted by Purkinje, that leads to what seems the most rational conclusion which our present knowledge will warrant respecting the general function of the cerebellum. Purkinje discovered that a current of electricity passed through the base of the head of a healthy person causes dizziness. It is natural to attribute this result to some action of electricity upon the cerebellum, especially in the light of the experiments already described.

Dizziness is due to some feeling of change in the relation between ourselves and outward objects. This feeling may be produced by an actual change in the objects or a change in ourselves. Illustrations are abundant, such as rapid riding in railroad-trains or violent swinging. It is a fact of importance in this connection, that alcoholism,