Page:Popular Science Monthly Volume 24.djvu/814

794 plates were depressed sufficiently to produce protruding eyes and baggy under-lids excelled in memory, oratory, philology, and the ability to acquire languages. This observation may be called the foundation of phrenology, for it led Gall to divide the mind into faculties, and to locate the faculty of speech in the anterior lobes of the cerebral hemisphere. This was the basis of his system. But the enthusiasm with which he constructed this system, and the sweeping deductions which he and his follower, Spurzheim, drew from this one prominent fact, failed to interest the scientific mind. Soon after this, without paying any regard to the conclusions of Gall and Spurzheim, the pathologists discovered how frequently the loss of speech co-existed with diseases or injuries of the anterior lobes of the brain, and that sometimes the only symptom of cerebral lesions was a loss of the power of articulate language. These observations led Bouillaud, in 1825, to divide the faculty of speech into two phenomena, internal speech—the faculty to create and to represent ideas—and external speech, or the co-ordinating power necessary to articulate the words created. In medical literature, the loss of the faculty of speech is termed aphasia, and when it affects the internal speech it is designated as amnesic aphasia, and when external speech is affected the term ataxic aphasia expresses it.

But without going into detail respecting the weighty pros and cons in the discussion of this subject during the last fifty years up to the present time, it is safe to state that the power of speech is twofold, namely, mental and motor. Now, as a mental fact, the faculty of articulate language implies perception, intellectual distribution of perception, excitation of emotion, will to enunciate. As an illustration: we see a man across the street; we recognize him as John Jones, from Johnsonville; we experience pleasure, and say, "My dear friend, I am glad to see you." Thus it will be seen that the mind as regards speech can be divided into perception, intellect, emotion, and will. These are the mental attributes, and the impairment of any one of them will interfere with the culminating act of speech. The perception may be impaired, then the friend across the street would not start the mental train. Furthermore, if perception was perfect and the intellect impaired, we would see the man, perceive the color of his hair and eyes, the style of his clothing, and so forth, but not be conscious that we had met him before, and that he was a friend. Still further, if the emotion was impaired and the two other faculties normal, we would see the man, know he was a friend, but not be stimulated to further action. Again, if the three above faculties were normal and will-power wanting, we would see, recognize, and wish to speak to him, but be powerless to do so. All the best evidence of recent times indicates that these faculties reside in the gray matter which is spread over the surface of the cerebral hemispheres, with their manifold sulci and convolutions, and the depth of which is an index of the intellectual power,