Let us add that the nature of the lesions just mentioned does not seem to have any relationship to the condition of the mental faculties. An anatomico-pathological grouping of the cases and a grouping according to the mental condition, far from being parallel, are frequently decidedly different. On the other hand, the extent of the lesions is of more importance. Diffuse lesions affect the mind more than those which are circumscribed—that is to say, limited to a certain part of the brain—as if the mental functions required the co-operation of the entire cerebral cortex. One will often find, for example, sound judgment in the subject of a marked paralysis, whilst it is very rare to find that good intelligence co-exists with any degree of microcephalus.
Let us emphasise the last fact we mentioned, the absence of any lesion. Some authorities have maintained that all conditions of mental deficiency and want of balance found in children are connected with definite diseases of which they are the symptoms. The question is unsettled. For our own part we adopt the following provisional statement: Mental deficiency and want of balance are peculiar mental conditions which it is often impossible to connect with definite pathological changes.
Thus, we do not know of any medical treatment which is likely to act upon the preceding lesions when they are present, and we do not think it is even possible to act upon them.
An exception must, however, be made of conditions due to insufficient secretion of certain glands. The type of these is cretinism. Marked cases of this condition are easy to recognise. The very appearance of the children is sufficient for an experienced eye—the stunted growth; the rough, wrinkled skin; the swollen eyelids half-concealing the eyes; the prominent belly; and the mental apathy. One also comes across abortive cases, where the above-mentioned characters are less marked; the sluggishness also is less. These latter cases are amenable to the same treatment as the former—namely, the ingestion of thyroid glands from the sheep.
This treatment stimulates growth and makes the child more lively; but what ultimately becomes of the cases so treated? The amelioration usually ceases whenever the treatment is dropped. But how far does this amelioration go? To what extent does the child profit by it? Lasègue has jocularly remarked that the average duration of an attack of typhoid fever (six weeks) represents the maximum time during which medical attention could be brought to bear upon a patient. One feels disposed to think he is right in face of the slight satisfaction one can obtain from the literature regarding a point of such importance.
Other cases of mental deficiency may be due to an alteration in the pituitary gland. It is for the doctor to find out whether there are any symptoms by which mental deficiency of such an origin can be recognised, and whether it is possible to prepare a suitable substance for replacing the absent secretion.
The number of cases amenable to treatment of this kind is, unfortunately, very limited.[13] We may even say that, as a general rule, we did not find amongst the school children we examined any cases of obesity or infantilism such as are sometimes described of a truly remarkable nature. Even children who were abnormally short looked their age. We have still, however, to mention one last influence—namely, poverty. Its part in the production of mental debility is scarcely defined. What are the exact effects upon intelligence of prolonged deficiency of nutrition? How can its action be isolated from that of other agents, such as alcoholism, which too frequently accompanies it? The complexity of such social studies sufficiently explains their present incompleteness. Let us recall the results we obtained from an inquiry of this kind; the children of parents in extreme poverty are retarded in their physical development more frequently than those whose parents are in easy circumstances. It is interesting to add that analogous inquiries with reference to intelligence have furnished similar results.
Apart from the preceding cases, the best that can be done is to treat the symptoms. The two principal agents at the disposal of the doctor are the bromides and hydrotherapy. Unfortunately, if the bromides are undoubtedly efficacious in certain cases of epilepsy, that is far from being the case in simple want of mental balance, in which cases they are at best useful adjuvants. As to hydrotherapy, and especially cold douches, their principal indication is in certain nervous affections, where their effect is to enable the subject to master the emotional reactions which are habitually exaggerated.
Lastly, the doctor can exert his moral influence to assist the educative work of the teacher in the special school. His less frequent intervention, the different motives of his advice, will often give him even more authority than the teacher. The suggestive effects of his intervention should be obtained, in our opinion, without resort to hypnotism.
3. Does the Mentally Defective suffer from any Definite Illness?—If the illness such as we have referred to affects those parts of the cerebral cortex which govern the muscles of a limb, one will find, in addition to the mental condition, paralysis with atrophy and contracture. But in addition to such very marked cases, there exist others in which sensory or motor affections, although slight, may hinder the progress of education.