SOMNAMBULISM AND SLEEP-WALKING. 511 



but are essentially automatic. Thus a person iu this condition will answer ques- 

 tions, obey commands involving a good deal of muscular exercise, and perform otner 

 complex actions without disturbing the connection of his ideas. When the state of 

 mental pre-occupation has disappeared, there may be no recollection of the acts that 

 have been performed. In the case of a person playing the piano and at the same 

 time carrying on a conversation we have a striking illustration of the simultaneous 

 performance of a mental and an automatic act. The mind is engaged with ideas, 

 and the spinal cord directs the manipulations necessary to the proper rendering of 

 the musical composition. A person who is not proficient in the use of the instrument 

 cannot at the same time play and converse with ease, because the spinal cord has not 

 acquired a sufficient degree of automatism, and the mind cannot be divided in its 

 action. Darwin has recorded a striking example of the independent action of the 

 brain and the spinal cord. A young lady was playing on the piano a very difficult 

 musical composition, which she performed with great skill and care, though she was 

 observed to be agitated and pre-occupied. When she had finished she burst into 

 tears. She had been intently watching the death-struggles of a favourite bird. 

 Though her brain was thus absorbed, the spinal cord had not been diverted from the 

 office of carrying on the muscular and automatic actions required for her musical 

 performance. 



Occasionally the attacks of somnambulism have 'been so long and so frequent, 

 that there is as much of a sleeping as there is of a waking state, and thus has 

 arisen the singular phenomenon known as " double consciousness." Trains 

 of thought are carried on from one attack to the next, though in the normal 

 interval the mind is quite unconscious of them. In a remarkable instance 

 of this kind, the patient, a servant girl, began by being subject to attacks of 

 extreme sleepiness ; next, in these sleeps she began to be talkative. Soon there 

 appeared to be some method in what she said; she personated an episcopal 

 clergyman, went through the baptismal service for three children, and delivered 

 an extempore prayer. Another time she thought she was a jockey at Epsom, and 

 rode round the kitchen on a stool. On awaking these pranks were forgotten, 

 although in succeeding fits she remembered all that had occurred. Thus one night 

 one of her fellow-servants was rude to her when somnambulistic. The next 

 day the insult was forgotten, but shortly afterwards she had another attack, and 

 told her mother about it. It is stated that education may be carried on, and even 

 languages acquired, during somnambulism, but this is very doubtful. 



The subjects of somnambulism not unfrequently suffer in addition from night- 

 mare. In nightmare there are generally apparitions, horrible or ludicrous, with 

 always a distinct consciousness of inability to move. It may arise from the presence 

 of indigestible food in the stomach, or from wind, or acidity. The suffering usually 

 commences with a disagreeable vision, and the sleeper attempts to escape from some 

 imaginary danger. Then he experiences a sense of suffocation, which increases 

 until there is an imperfect consciousness that he is in bed. But still there continues 

 the tormenting oppression from the weight on the chest, which keeps him lying on 

 his back. The oppressed breathing becomes more and still more painful ; palpita- 

 tion of the heart sets in, attempts are made to move the arms, but it is found 



