It does not by any means always depend on over-study, though I do not remember meeting with it in children who had not yet gone into the school-room; and I have frequently found it dependent on too continuous application, though the number of hours devoted to study in the course of the day may not have been by any means excessive.
The child's brain soon tires, and the arrangement, so convenient to parents of morning lessons and afternoon play, works far less well for it than if the time were more equally divided between the two.
The attacks not infrequently come on on waking in the morning, and rapidly become worse, the pain, which is almost always referred to the forehead, being attended with much intolerance of light and sound, with nausea, and often with actual vomiting. Like the vomiting of sea-sickness, however, previous stomach disorder has no necessary share in its production, and I may add, indeed, that it is often difficult to assign any special exciting cause for the attack. The suffering is more often relieved by warm or tepid than by cold applications, and not infrequently pressure or a tight bandage greatly mitigates it. In no case does the attack last more than twelve hours—usually not more than half that time; it passes off with sleep, and leaves the patient weak and with a degree of tenderness of the head to the touch.
Such attacks may occur every fortnight, ten days, or even oftener, but their very frequent return, instead of increasing apprehension, should diminish anxiety. A first attack, indeed, may seem as though it threatened mischief, till it is seen how speedily and completely it passes off, and when afterwards a second or a third attack comes on with the same severity of onset, the same rapid worsening, and the same quick passing away, you will feel convinced that the symptoms have no grave meaning.
There is a headache of quite a different kind to which I must for a moment refer, that, namely, which depends entirely on imperfect vision, and for which spectacles are the remedy, not physic. The infirmity is not noticed during the first few years of life, but in later childhood, when a tolerably close attention to study has become necessary. Some of the minor degrees of short-sightedness, and want of power of adaptation of the eyes, such as exists in the aged, soon begin to interfere sensibly with the child's comfort, and the strain to which the eyes are subject produces a constant pain over the brow, the cause of which is often unsuspected.[13]
In all cases, therefore, in which a child complains of constant pain over the brow for which there is no obvious cause, it is well to take the opinion of an oculist, who can best ascertain the power of reading at different distances and with each eye separately, and the real cause of symptoms which had occasioned much anxiety is thus often brought to light.
Night Terrors.—Before taking leave of the disorders of the nervous system, I must briefly mention the Nightmare, or Night Terrors of children, which often cause a degree of alarm quite out of proportion to their real importance.
It happens sometimes that a child who has gone to bed apparently well, and who has slept soundly for a short time, awakes suddenly with a sharp and piercing cry. The child will be found sitting up in bed, crying out as if in an agony of fear, 'Oh dear! Oh dear! take it away! father! mother!' while terror is depicted on its countenance, and it does not recognise its parents, who, alarmed by the shrieks, have come into its room, but seems wholly occupied by the fearful impression that has roused it from sleep. By degrees consciousness returns; the child now clings to its mother or its nurse, sometimes wants to be taken up and carried about the room, and by degrees, sometimes in ten minutes, sometimes in half-an-hour, it grows quiet and falls asleep; and then usually the rest of the night is passed undisturbed, though sometimes a second or even a third attack may occur before daybreak.
Seizures of this kind may come on in a great variety of circumstances, and may either happen only two or three times, or may continue to recur at intervals for several weeks. The great point, however, to bear in mind is that they depend invariably on some disorder of the stomach or bowels, and are never an evidence of the commencement of real disease of the brain.