Besides the motor aphasia, just mentioned, there is another type, called sensory aphasia, or, more precisely, auditory aphasia. In pure auditory aphasia there is no inability to pronounce words or even to speak fluently, but there is, first, an inability to "hear words", sometimes called word deafness, and there is often also an inability to find the right words to speak, so that the individual so afflicted, while speaking fluently enough and having sense in mind, misuses his words and utters a perfect jargon. One old gentleman mystified his friends one morning by declaring that he must go and "have his umbrella washed", till it was finally discovered that what he wanted was to have his hair cut. The cortical area affected in this form of aphasia is located a little further back on the surface of the brain than In the immediate neighborhood of the auditory area proper (or of the "auditory-sensory area", as it may well be called), are portions of the cortex intimately connected by axons with it, and concerned in what may be called auditory perceptions, i.e., with recognizing and understanding sounds. Probably different portions of the cortex near the auditory-sensory center have to do with different sorts of auditory perception. At least, we sometimes find individuals who, as a result of injury or disease affecting this general region, are unable any longer to follow and appreciate music. They cannot "catch the tune" any longer, though they may have been fine musicians before this portion of their cortex was destroyed. In other cases, we find, instead of this music deafness, the word deafness mentioned just above. The jargon talk that so often accompanies word deafness reminds us of the fact that speech is first of all auditory to the child. He understands what is said to him before he talks himself, and his vocabulary for purposes of understanding always remains ahead of his speaking vocabulary. It appears that this precedence of auditory speech over motor remains the fact throughout life, in most persons, and that the auditory speech center is the most fundamental of all the speech centers, of which there is one more not yet mentioned, used in reading.
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