PSYCHIC FUNCTIONS OF THE CEREBRUM. 779 



of the activity of the ganglion-cells of the cerebral cortex, induced by slight per- 

 sistent irritation of the face (by means of gentle stroking, feeble electrical cur- 

 rents) , or of the optic nerve (staring at a bright button) , or of the auditory nerves 

 (uniform sounds). Intense and sudden irritation of the same nerves rapidly 

 abolishes the state, particularly blowing on the face. Berger attaches especial 

 significance to the psychological influence of the artificially excited conception and 

 attention and their concentration upon certain portions of the body. Schneider 

 believes that the abnormal exclusive concentration of consciousness upon the 

 act of hypnotization furnishes the cause for the phenomenon. The first hyp- 

 notization of an individual is effected with greatest difficulty, and long fixation 

 of a brilliant object, which Braid recommended as early as 1841 for the develop- 

 ment of an anesthetic state, appears in this connection to be of special significance; 

 although the ability to be hypnotized varies greatly in different individuals. On 

 repeated hypnotization the condition can often be induced with extreme ease, 

 for example by means of simple pressure upon the brow or by placing the subject 

 passively in a definite position or by stroking. In some individuals the mere 

 conception of the approach of the condition is sufficient to induce it, as Cardanus 

 observed in himself in 1553. 



The hypnotized individual is first incapable of opening the closed eyelids. 

 There is then spasm of the accommodative apparatus of the eye, the range of 

 accommodation being diminished, and abnormal positions of the eye are observed. 

 Next there appear irritative phenomena in the distribution of sympathetic nerves 

 arising from the medulla oblongata, such as widening of the palpebral fissure, 

 dilatation of the pupils, exophthalmos, acceleration of respiration and of pulse. 

 At a certain stage a marked increase in the acuity of the special senses can at 

 times be demonstrated, and also of muscular sensibility. Later on, analgesia may 

 appear, with preservation of tactile sensibility and loss of the sense of taste. 

 The temperature-sense disappears with greater difficulty, and still later the senses 

 of sight, smell and hearing become affected. The stimuli affecting the organs of 

 special sense cause no conscious sensory impressions on account of the suspension 

 of consciousness. At the same time, however, the irritation of the organs of 

 special sense may induce movements on the part of the hypnotized individual; 

 such as unconscious acts that appear to be voluntarily executed in imitation of 

 others. In this way is to be explained the fact that the hypnotized individual 

 appears to perform even foolish acts on command, while he imitates movements 

 first made by the experimenter, without consciousness of the significance of 'his 

 acts. In individuals with greatly increased reflex irritability voluntary move- 

 ments may excite reflex spasm, for example inability to make coordinated speech- 

 movements. 



According to Griitzner there are several fundamental types of hypnotism: (i) 

 Quiet sleep, words being still understood, and occurring especially in girls. (2) 

 In consequence of increased reflex irritability of the transversely striated muscles, 

 which may persist for days, groups of muscles become contracted, especially in 

 strong persons. At the same time, there may be ataxia, and the muscles may 

 fail to perform their function. Hypnotized individuals can be placed in positions 

 of varied kind artificial catalepsy. In the stage of hysterical lethargy the 

 tendon-reflexes are at times increased. At the same time the muscles become 

 firmly contracted as soon as they or their nerves are pressed upon. Nerve and 

 muscle in the cataleptic state exhibit increased irritability to the constant current 

 and diminished irritability to the faradic current. In the condition of hysterical 

 catalepsy the tendon-reflexes are often entirely absent. (3) Command-autonomy, 

 in which the hypnotized individuals are obedient in shallow sleep, at first with 

 still preserved consciousness. When grasped by the hand or stroked upon the 

 head they perform involuntary movements, such as running about, dancing, 

 riding upon a chair and the like. The effects of so-called suggestion are peculiar, 

 that is conceptions can be aroused in the hypnotized subject by suggestion and 

 these may dominate the impulses and sensations of the individual for a consider- 

 able time. (4) Hallucinations occur, and only in certain individuals, on gradual 

 awakening from deep sleep. The hallucinations, generally of phenomena related 

 to fire and olfactory impressions, are usually quite profound, both the agreeable 

 as well as the frightful ones, and they often recur in dreams. (5) Imitation is rare. 

 Gross movements, such as walking, are readily imitated; more delicate or even 

 the most delicate, principally in the uneducated, occur less commonly. Echo- 

 speech can be induced by pressure upon the neck and speaking into the pharynx, 

 against the epigastrium and against the nape of the neck. Pressure upon the 



