The Story of the Mind

by James Mark Baldwin

If the fibres coming out from the speech zone be impaired, so that the impulses can not go to the muscles of articulation and breathing, we have Subcortical Motor Aphasia. Its peculiarity is that the person knows perfectly what he wants to say, but yet can not speak the words. He is able to read silently, can understand the speech of others, and can remember music; but, with his inability to speak, he is generally also unable to write or to perform on a musical instrument (yet this last is not always the case). Then we find new variations if his "lesion"—as all kinds of local nervous defects are called—is in the brain centre in the Rolandic region, where arise the memories of the movements required. In this latter case the aphasic patient can readily imitate speech so long as he hears it, can imitate writing so long as it lies before him, but can not do any independent speaking or writing for himself. With this there goes another fact which characterizes this form of aphasia, and which is called Cortical, as opposed to the Subcortical Motor Aphasia described above, that the person may not be able even to think of the words which are appropriate to express his meaning. This is the case when those persons who depend upon the memories of the movements of lip and tongue in their normal speech are injured as described.

Besides the two forms of Motor Aphasia now spoken of, there are certain other speech defects which are called Sensory Aphasia. When a lesion occurs in one of the areas of the brain in the speech zone in which the requisite memories of words seen or heard have their seat—as when a ball player is struck over the sight centre in the back of the head—special forms of sensory aphasia show themselves. The ball player will, in this case, have Visual Aphasia, being unable to speak in proportion as he is accustomed in his speaking to depend upon the images of written or printed words. He is quite unable to read or write from a copy which he sees; but he may be able, nevertheless, to write from dictation, and also to repeat words which are spoken to him. This is because in these latter performances he uses his auditory centre, and not the visual. There are, indeed, some persons who are so independent of vision that the loss of the visual centre does not much impair their normal speech.

When, again, an injury comes to the auditory centre in the temporal region, we find the converse of the case just described; the defect is then called Auditory Aphasia. The patient can not now speak or write words which he hears, and can not speak spontaneously in proportion as he is accustomed to depend upon his memories of the word sounds. But in most cases he can still both speak and write printed or written words which he sees before him.

These cases may serve to give the reader an idea of the remarkable delicacy and complexity of the function of speech. It becomes more evident when, instead of cases of gross lesion, which destroy a whole centre, or cut the connections between centres, we have disease of the brain which merely destroys a few cells in the gray matter here or there. We then find partial loss of speech, such as is seen in patients who lack only certain classes of words; perhaps the verbs, or the conjunctions, or proper names, etc.; or in the patients who speak, but yet do not say what they mean; or, again, in persons who have two verbal series going on at once, one of which they can not control, and which they often attribute to an enemy inside them, in control of the vocal organs, or to a persecutor outside whose abuse they can not avoid hearing. In cases of violent sick headache we often miscall objects without detecting it ourselves, and in delirium the speech mechanism works from violent organic discharges altogether without control. The senile old man talks nonsense—so-called gibberish—thinking he is discoursing properly.

In the main cases of Aphasia of distinct sensory and motor types psychological analysis is now so adequate and the anatomical localization so far advanced that the physicians have sufficient basis for their diagnosis, and make inferences looking toward treatment. Many cases of tumour, of clot on the brain, of local pressure from the skull, and of hæmorrhage or stopping up of the blood vessels in a limited area, have been cured through the indications given by the particular forms and degrees of aphasia shown by the patients. The skull is opened at the place indicated by the defect of speech, the lesion found where the diagnosis suggested, and the cause removed.

This account of Localization will suggest to the reader the truth that there is no science of Phrenology. No progress has been made in localizing the intelligence; and the view is now very general that the whole brain, with all its interchange of impulses from part to part, is involved in thinking. As for locating particular emotions and qualities of temperament, it is quite absurd. Furthermore, the irregularities of the skull do not indicate local brain differences. It is thought that the relative weight of the brain may be an indication of intellectual endowment, especially when the brain weight is compared with the weight of the rest of the body, and that culture in particular lines increases the surface of the cortex by deepening and multiplying the convolutions. But these statements can not be applied off-hand to individuals, as the practise of phrenology would require.

Defects of Memory—Amnesia.—The cases given just above, where the failure of speech was seen to be due to the loss of certain memories of words, illustrate also a series of mental defects, which are classed together as Amnesias. Any failure in memory, except the normal lapses which we call forgetfulness, is included under this term. Just as the loss of word memories occasions inability to speak, so that of other sorts of memories occasions other functional disturbances. A patient may forget objects, and so not know how to use his penknife or to put on his shoes. He may forget events, and so give false witness as to the past.

One may forget himself also, and so have, in some degree, a different character, as is seen, in an exaggerated way, in persons who have so-called Dual Personality. These patients suddenly fall into a secondary state, in which they forget all the events of their ordinary lives, but remember all the events of the earlier periods of the secondary personality. This state may be described as "general" amnesia, in contrast to the "partial" amnesia of the other cases given, in which only particular classes of memories are impaired.

The impairment of memory with advancing years also illustrates both "general" and "partial" Amnesia. The old man loses his memory of names, then of other words, then of events, and so gradually becomes incapable of much retention of any sort.

Defects of Will—Aboulia.—A few words may suffice to characterize the great class of mental defects which arise on the side of action. All inability to perform intentional acts is called Aboulia, or lack of Will. Certain defects of speech mentioned above illustrate this: cases in which the patient knows what he wishes to say and yet can not say it. This is the type of all the "partial" Aboulias. There may be no lack in determination and effort, yet the action may be impossible. But, in contrast with this, there is a more grave defect called "general" Aboulia. Here we find a weakening of resolution, of determination, associated with some lack of self-control showing itself frequently by a certain hesitation or indecision. The patient says: "I can not make up my mind," "I can not decide." In exaggerated cases it becomes a form of mania called "insanity of doubt." The patient stands before a door for an hour hesitating as to whether he can open it or not, or carries to its extreme the experience we all sometimes have of finding it necessary to return again and again to make sure that we have locked the door or shut the draught of the furnace.