Page:Popular Science Monthly Volume 35.djvu/761

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ple whose fingers have been cut off often say that they have pain in the missing finger, and when you are seated on a hard or uncomfortable chair your foot "goes to sleep."

Now, just as the fingers are joined to the brain we must believe that the other organs are joined to it. Thus the eye sends in its thousands of little threads to one part of the brain surface, the ear to another, the nose and tongue to another. So that each of

PSM V35 D761 Direction of some of the fibers of the cerebrum.jpg

Fig. 2.—Diagrammatic Representation of the Direction of some of the Fibers in the Cerebrum (Le Bon) The foldings of the surface; the association fibers joining different regions of the surface with each other; and the fibers passing down to the organs of sense are shown.

the organs of sense is related to a special region of the brain. And each of these regions receives messages from its own particular organ and from no other. That is what is meant by the term localization of brain functions; namely, that each power of sensation can be assigned to a location of its own. This idea aids very materially our conception of the senses. The sense of sight, for example, can not be thought of as dependent upon the eye alone, but upon the eye and the visual part of the brain surface with their connecting threads. And, after all, we must admit that we do not really see with our eyes or hear with our ears. Why does your friend want to hurry through an art gallery, while you wish