Thus, during somnambulism mental processes of a high character may go on, but they leave no recollection behind them.
A curious circumstance is that a person walk ing in sleep will move round obstacles in his path, and guide his course just as if he were fully awake and fully conscious of all his move ments. This may be explained by reflex action (see p. 132), the objects making impressions on the eyes, and those impressions through the nervous ganglia at the base of the brain stimu lating in a habitual way certain centres for movement. Often, however, somnambulists walk into dangers that cause their death.
The ordinary forms of sleep-talking and sleep walking are common enough in children.
The treatment of such conditions mustlargely depend on the person, whether child or adult. Anything that over-excites should be avoided, whether over-feeding, or feeding with too rich diet, or over-exercise, or over-study, or the over excitement of pleasure. At the same time it must be looked to that the person, and espe cially the child, is not given to very deep slum ber because of poverty of blood, and consequent insufficient nourishment of the brain for its healthy activity. Means should be taken if possible to prevent the occurrence of sleep walking by awaking the person during the night. If the tendency is to walk at a certain time, this will be especially beneficial by anti cipating the period, and so gradually weakening the habit. Children of this tendency should never be allowed to sleep alone ; and in all cases precaution should be taken to prevent a sleep walker from opening windows, outer doors, &c.
For children, bromide of potassium, in 5 grain doses, at bed-time, is specially valuable in allaying any excitable condition from which the disorder may spring.
Sleeplessness (Insomnia) is of many kinds, from absolute wakefulness, accompanied by a busy brain, probably the result of it, to the dull stupor that is not true sleep, or the broken fiftfnl snatches disturbed by dreams and fancies, generally of a disagreeable sort. Like head ache, it has a variety of causes. Overwork and worry is a common cause. The business or professional man, especially one who has to sit late busy with books or ideas, if lie goes straight off to bed, very likely sleeps little or badly. Similarly, the woman who has many engrossing household cares, and who, with run ning about and directing affairs, is intensely fatigued, is likely to pass a night that, with sleep or without it, will probably prove un profitable in the morning. Badly ventilated
apartments can provoke it. Indigestion, con stipation, and heavy suppers are well known hindrances to sleep.
Treatment.---It will be found that quiet rest without work of any sort for an hour at least before retiring is the best preparation the ex hausted business man, brain worker, or house wife can have for bed. Every clergyman who has had an evening service knows that if he wishes to sleep he must let some of his excite ment work off before going to bed, and he usually aids its departure with a quiet smoke and talk by the fireside. To a mild smoke to the man accustomed to it there is no possible objection. Brisk evening exercise in the open air, the use of the cold bath, or the mustard foot-bath, to draw the blood from the head, may be tried. Treatment by the high-frequency electric current is well worth a good trial.
None of these methods is of any avail to many people, and meanwhile the sleeplessness becomes painful, exhausting, or killing. Some drug must be resorted to; which should it be? Not opium, and not chloral hydrate. The use of both of these grows perniciously. The man who accustoms himself to his nightly dose of opium requires increasingly larger and larger doses, and soon begins to use the drug for relief from other troubles. Chloral hydrate, too, gains a wretched mastery, and has had its countless victims found dead in the morning, because in their confidence in its use an overdose had by mistake been taken. Again the safe drug is bromide of potassium-30-grain doses in a wine glassful of water. Failing it, one of the newer remedies, trional or veronal, may be employed. [Refer to section on HYPNOTICS.] Wakefulness as the result of indigestion is to be treated by the removal of the cause.
Nightmare is a condition of nervous activity that occasions dreams of a very vivid and usu ally distressing character. The anguish of the situation is increased by the want of voluntary power, and the inability to move or cry out. When this is at last, after a seemingly intense struggle, effected, the person awakes. In chil dren nightmare•night-terrors as it is some times cal led—occurs, in which the child wakes up some hours after going to sleep, in great fright.