PROBLEMS OF ABNORMAL PSYCHOLOGY 773 



another personality? There is not a failure of perception of the ego, 

 but a splitting of the ego itself. What has produced it? 



Any theory to be sufficient must take into consideration all the 

 facts not only of abnormal but of normal dissociations, including 

 those artificially induced by experimental devices (suggestion, 

 automatic writing, etc.)- When we do this we find in the first place, 

 as already pointed out, facts indicating a normal process for dis- 

 sociating consciousness, through which process normal and abnormal 

 phenomena may be correlated. Normal absentmindedness, certain 

 types of -normal amnesia, sleep, spontaneous somnambulism, hyp- 

 nosis, etc., can experimentally be shown to be types of dissociation, 

 splitting of the ego, differing from one another in the extent and 

 pattern of the fields of consciousness remaining to the personal ego. 

 The process which brings these states about is probably fundamen- 

 tally the same as that governing the abnormal splitting of con- 

 sciousness. 



In the second place a study of abnormal and induced dissociation 

 shows that, while normal syntheses and automatisms largely follow 

 psychological laws, the lines of disaggregation do not follow the lines 

 mapped out by these laws. For instance, they do not follow the 

 boundaries of associated ideas. 



The hand that performs automatic writing becomes anesthetic, 

 though the subconscious ideas which control the hand have nothing 

 to do with tactile sensation. A subconscious fixed idea of fear of 



personal injury robs the personal consciousness of our subject M 1 J 



of perceptions from the peripheral field of vision and from one half 

 of his body. In another subject all the memories for a certain epoch 

 in her life disappear in consequence of a shock. An emotional shock 

 in A. P., excited by a slight fall during a high-kicking act, robs the 

 personal consciousness of the power to move the arm and leg which 

 are rigid in contracture. In Madam D., a subject of Charcot and 

 Janet, continuous amnesia for each succeeding moment of the day 

 follows the announcement of a piece of bad news. There are no 

 psychological associations in any of these examples between the 

 ideas and the resulting dissociations, and psychologically we can 

 find no reason why sensory and motor images are dissociated in 

 one case, and memories in another. It would seem from the points 

 of view of our present knowledge that we shall have to look for an 

 explanation in some physiological process. All must admit that the 

 final explanation must be in terms of the neuron, in the dissociation 

 of the as yet unknown neuron systems which are correlated with 

 the psychological systems. But without attempting such an ex- 

 planation, what I wish to point out is that the data of abnormal 



1 Boston Medical and Surgical Journal, vol. CL, no. 25, pp. 674-678, June 23, 

 1904. 



