Another was suddenly aroused from a sound sleep by the slamming of a window-shutter by the wind. He sprang instantly from his bed, and, seizing a chair that was near, hurled it with all his strength against the window. The noise of the breaking of glass fully awakened him. He explained that he imagined some one was trying to get into the room and had let his pistol fall on the floor, thereby producing the noise which had startled him.
In another case a man dreamed that he heard a voice telling him to jump out of the window. He at once arose, threw open the sash, and jumped to the ground below, fortunately only a distance of about ten feet, so that he was not injured beyond receiving a violent shock. Such a case as this appears to me to be very similar to those described by Dr. Beard in all its essential aspects.
A few years ago I had a gentleman under my charge who would attempt to execute any order given him while he was asleep by a person whispering into his ear. Thus, if told in this way to shout, he shouted as loud as he could; if ordered to get up, he at once jumped from the bed; if directed to repeat certain words, he said them, and so on.
I am not able to give any certain explanation of the phenomena of miryachit or of the "Jumpers," or of certain of those cases of sleep-drunkenness which seem to be of like character. But they all appear to be due to the fact a motor impulse is excited by perceptions without the necessary concurrence of the volition of the individual to cause the discharge. They are, therefore, analogous to reflex actions, and especially to certain epileptic paroxysms due to reflex irritations. It would seem as though the nerve cells were very much in the condition of a package of dynamite or nitro glycerin, in which a very slight impression is sufficient to effect a discharge of nerve force. They differ, however, from the epileptic paroxysm in the fact that the discharge is consonant with the perception—which is in these cases an irritation—and is hence an apparently logical act, whereas in epilepsy the discharge is more violent, is illogical, and does not cease with the cessation of the irritation.
Certainly the whole subject is of sufficient importance to demand the careful study of competent observers.
Read before the New York Neurological Society, February 5, 1884.
"Observations upon the Korean Coast, Japanese-Korean Ports, and Siberia, made during a journey from the Asiatic Station to the United States, through Siberia to Europe, June 3 to September 8, 1882." Published by the United States Navy Department, Washington, 1883, pp. 51.