CHAPTER XII

PATHOLOGICAL CONDITIONS IN WHICH THE MEMORY IS AFFECTED

I. GENERAL DIMINUTION OF THE MEMORY.

In all cases in which, by any means whatsoever, there is a loss of nervous force not immediately replaceable, there is a corresponding diminution of the memory.

In cases of congenital idiocy we notice that a very feeble power of retaining impressions is usually possessed. This we should naturally expect from an examination of the brain, which is usually found to be considerably undersized. On this account, those faculties, which were under the average size, would perceive impressions very feebly, and recollect them with equal difficulty.

In idiots we have very strong confirmation of the view that the faculties of the mind are multiple, as we often find, with a general deficiency of mental power, some extraordinary capacity in one particular direction, and this can be explained by supposing that with a general deficiency in the size of most of the faculties, one of them is considerably larger than usual. We find that the function of the faculty in question, when occurring in this way, is exactly the same as in a sane person, and acts in the same way when of propor

tionate size. Thus, we have singing idiots, who can remember tunes with the most perfect accuracy; and calculating idiots, who show a special predilection for figures, and can remember them to an extraordinary extent. Then there are others who have a special aptitude for drawing, learning words (simply as sounds, without any relation to their meanings), localities, periods of time, etc.

A case is related by Forbes Winslow of an idiot who could remember the day when any person had been buried in the parish, for thirty-five years, and could repeat with unvarying accuracy the name and age of the departed, and the mourners at the funeral. Out of the line of burials he had not one idea, and could not give an intelligible reply to a single question, nor be trusted even to feed himself.

It is the same with weak-minded individuals. We often find persons, almost idiotic in their general mental capacity, who show some special aptitude for music, mimicking, or some special kind of memory. Genius is usually only partial, a Crichton being very

rare.

After any violent injury there is usually some general diminution in the power of the memory. All injuries which are violent enough to produce a severe shock are followed by deficiency in the recollecting power, for a certain time; this passes off as the expenditure of the nervous force becomes gradually replaced.

Injuries to the head are especially likely to be followed by loss of memory, and in many cases the individual says that his memory is not as good as it was before he sustained the injury.

Besides the general diminution in the power of the memory in these cases, there is often a loss of memory for a certain period of time; this will be spoken of under partial loss of memory.'

The next class of cases are those of functional diminution in the brain power, and corresponding diminution in the intensity of the impressions. We find in these cases that the individual can remember impressions which have acquired the requisite intensity, especially those received before the period of functional disturbance. During the period of functional disturbance, there is a want of power to retain impressions, received during that time, though previous impressions are revived; so it is quite possible to have a long conversation with a person suffering from considerable functional disturbance, without being able to detect that there is anything peculiar about him, as in many cases he will talk fluently, express opinions on various topics, and apparently conduct himself in all ways, conducing to a belief that he is in a perfectly normal condition.

Yet that same man may feel quite unable, the next day, to recollect whom he spent the evening with, and the events which took place, and might even be unable to recognise the persons he saw, even on meeting them the next day.

I have especially studied the condition of the memory in epilepsy, in which there seems to be a great loss of nerve-force, and compared it with other conditions in which there is a functional diminution in the power of the faculties to establish a memory; and have found that the above remarks apply to all other functional cases. As would be expected, when a large

faculty is present in any of these individuals, the special impressions particular to this faculty are remembered, whilst the others are forgotten. In short, it will be found that it is the functions of the faculties which are specially interfered with, the sub-intellectual processes taking place as before; if an idea be not brought before the mind by the direct revival, the individual is not able to intensify some component so as to increase the power of contiguous association, and he feels very disinclined to make the attempt.

The following cases illustrate the above-mentioned condition.

Memory in Epilepsy.

(i.) J. H. Male, 183.

This was a case of traumatic epilepsy, the first fit occurring when he was twelve years old.

He had an intelligent face, and spoke in a bright sensible way, giving his account very plainly.

He said his memory got worse after each fit, and was now very bad. If he were told to do anything by his father, he always forgot to do it. If he read a book, unless there was something very startling in it, he would not recognise that he had read it, the next day. He said he was not able to recognise a person directly after he had seen him. He could remember circumstances which happened, and books that he had read, before he commenced to have fits, with ease. He distinguished himself at arithmetic when at school, but he could now only calculate on paper, and not mentally, as he used to do, and had lost his liking for figures, taking especial interest in mechanical pursuits, such as fretwork.

He said he felt very despondent, and inclined to commit suicide.

Memory in Epilepsy.

(ii.) R. N. Male, 28.

The first fit occurred when he was twenty-four, without any apparent cause at the time. He had received a blow on the head when thirteen years old, and was unconscious for fifteen hours, never afterwards properly regaining his health. He was an intelligent-looking man, and gave his answers readily and plainly.

His memory, previous to the occurrence of the fits, had been very good, but had since become very bad. He said he should not be able to recognise me if he were to meet me the next day. He forgot persons ten minutes after he had seen them. He said that when he read the paper-reading about subjects especially interesting to him, as accounts of murders-directly he had finished reading, he would go into the next room and speak about what he had just been perusing, to another person, and would give quite a wrong account and keep to it until he found that he was wrong by referring to the paper. I read a paragraph to him ending with the word charity,' and immediately afterwards asked him what the last word was. He was unable to say. I then said, 'Was it charity?' and repeated the question three or four times, and even then he seemed very doubtful.

He said he could remember events which occurred when he was five years old and later, much better than those of the present time. He still had a very good memory for tunes, and said that, after hearing a tune in the street, he was able to go home and play it. He