48 THE, POPULAR SCIENCE MONTHLY. 



diverted. But the circumstances attending the operations with the 

 lauo-hingr-sras were again calculated to absorb the attention in other 



GOO O 



directions and thus divert it from the shoulder. The result was the 

 immediate relaxation of the muscles involved in maintaining the shoul- 

 der in a fixed position. In the absence of any local disease which could 

 cause local irritation and reflex muscular contraction, this must have 

 been kept up by direct volition. An important evidence of its volun- 

 tary character, besides that which is afforded by the prompt relaxation 

 through opposite mental influence, was the immediate and very great im- 

 provement in the patient's general health. She was, in fact, completely 

 exhausted by a labor which she was not conscious of doing, but when 

 she ceased this continuous effort she at once improved in strength. 

 The same improvement in the general health, but in an even more 

 marked degree, was manifested in the second case above related. 



Adult life is not alone liable to the class of mental influences which 

 we are now discussing. Young persons and even quite small children 

 are frequent subjects for psycho-biological study. 



But mental influence over bodily function is exhibited not alone in 

 connection with the muscles in determining their relaxation or rigidity, 

 in certain cases; but what are called bodily sensations are even more 

 dominated by the mental timbre of the individual. We have local and 

 general hyperesthesias and anaesthesias both as transient and as per- 

 manent conditions from this cause. I feel obliged to employ phrases as 

 they are employed in common use, but, strictly speaking, there are no 

 bodily sensations, for all sensation is mental there is and can be no 

 other. The most that we can strictly say is that we feel in the mind, 

 but refer the cause of such feeling to certain locations in the body. 

 Stick a pin in my flesh, and whether I feel it or not, and how much I 

 may feel it, will depend wholly on the state of my mind. If obscured 

 by an anaesthetic or if asleep, provided the impinging on the nerves 

 is not sufficient to waken me, or even if my attention be very much 

 absorbed, I shall not be conscious of the pricking. On the other 

 hand, if I have been pricked before so that my fears are aroused, or 

 if I am worried or weary or ill, then the pain is many hundred times 

 greater than under the opposite circumstances. We go to a dentist 

 one day when we are in a hurry, and with the mind troubled about some 

 matter. The drilling of his little instrument is agony. We leave and 

 return the next day with plenty of time, and our business settled. The 

 dentist drills still deeper into the same cavity while we sit in com- 

 parative comfort. 



But not only the same person has different degrees of sensation at 

 different times, according to his mental timbre at the time, but different 

 individuals and different classes of persons feel both pleasures and pains 

 more or less according to their individual or class elevation in the intel- 

 lectual scale. If a knife were thrust into the flesh, in corresponding 

 locations and to the same depth, in twenty people, no two would feel 



