12 Am. Journ. Med. Science, Jan., 1882.
13 Animal Magnetism: Physiological Observations, by Rudolph Heidenhain, Prof. Physiology in the University of Breslau, London, 1880.
14 Etudes cliniques sur l'Hystero-epilepsie, ou Grande Hystérie.
The method of Heidenhain was similar to that employed by Braid. The latter, however, did not make use of passes. In the first place, the individual was made to gaze fixedly at a shining faceted glass button for some six or eight minutes, the visual axes being made to converge as much as possible. Heidenhain, like Braid, found the most advantageous direction of the visual axes to be that of upward convergence. According to Carpenter, in the fixation this upward convergence is very important; it suffices of itself in blind people or in the night to produce hypnosis. After the fixation of gaze had been continued for some six or eight minutes, the operator stroked over the face, without immediately touching the surface, from the forehead to the chest, after each pass bringing the hands, which were warm, around in an arc to the forehead again. He either allowed the eyelids to be closed or gently closed them. After ten or twelve passes he asked the person to open his eyes. When this occurred without hesitation or with only slight difficulty, he again made the person stare at the glass for some six minutes, and then repeated the passes, which often brought about the hypnotic state when the simple fixation did not succeed.
The symptoms of the hypnotic state were in the main those which have just been described as the symptoms of catalepsy—namely, diminution of consciousness, insensibility, increased reflex irritability, and fixity of the body or limbs in any position given.
In the slighter forms of hypnotism the subjects were able to remember what had occurred during their apparent sleep. In more fully-developed forms they had no remembrance of what had taken place, but by giving hints and leading questions of their various actions they were able to call them to mind. In the most complete forms of hypnotism no remembrance whatever was retained. It can nevertheless be proved that even during the most completely developed hypnosis sensory perceptions take place, but they are no longer converted into conscious ideas, and consequently are not retained by the memory; and this is undoubtedly because the hypnotized individuals have lost the power of directing their attention to their sensations.
A symptom of the hypnotic state in its most complete development was highly marked insensibility to pain. A pin could be run right into the hand, and only an indistinct feeling of contact was brought about. Immediately on awaking the full sense of pain was again present. The fact that the tactile sense and the sense of pain are distinct was corroborated.
Increased reflex irritability and tonic spasm of the voluntary muscles accompanied the hypnotic condition. Stroking the flexible right arm of a subject, it at once became stiff, since all the muscles were thrown into a state of reflex spasm. Reflex muscular contraction spread over the body when certain definite cutaneous surfaces were irritated. With slight increase of reflex irritability those muscles alone contracted which lay immediately under the area of the skin which had been stroked. Stroking the ball of the thumb caused adduction of the thumb. Stimulating the skin over the sterno-mastoid caused the head to assume the stiff-neck position. When the irritability was somewhat more increased, by a continuous irritation of a definite spot of skin neighboring and even distant groups of muscles could be set into activity. Heidenhain stroked continuously the ball of the left thumb of his brother, when the following muscle-groups were successively affected with spasm: left thumb, left hand, left forearm, left upper arm and shoulder, right shoulder and arm, right forearm, right hand, left leg, left thigh, right thigh, right leg, muscles of mastication, muscles of the neck.
From a study of such phenomena Heidenhain was inclined to consider that the hypnotic state was nothing more than artificially produced catalepsy.
The possibility of fixing any part of the body in any given position constituted an essential factor in the exhibition of Hansen. He made one of his subjects, for instance, sit before him in a chair, and adapted the hands to the seat so that his fingers grasped the edges. After hypnotizing him he stroked along his arms, and his fingers took convulsive hold of the edges of the seat. Placing himself in front of the subject, he bent forward; the subject did the same. He then walked noisily backward, and thereupon the subject followed him through the hall, carrying his chair with him like a snail its shell.