STUDY OF CHOREA. 361 



tions are not readily changeable by the action of 

 external stimuli, indicate the brain defect. 



In studing chorea by these methods, it has been 

 possible to show that cases differ from one another 

 in the character of the movements ; in some cases 

 the movements are singularly simple, in others each 

 gross movement is compounded of several smaller 

 ones. Again, it has been possible to show what 

 causes increase or diminish the amount of move- 

 ment in a limb; the effects of talking to the 

 patient, keeping her in darkness, making her sit 

 up in bed, etc., in as far as these circumstances 

 affect movement can be investigated. Tracings 

 have been taken showing ankle-clonus; senile 

 tremor; movements of the sternum in health and 

 in chorea; the movements of athetosis, and those 

 due to the sucking of an infant, etc. ; the move- 

 ments of the limbs due to pulsation. 



I trust that in this chapter it has been shown 

 that there is reason for trying to describe brain 

 conditions in terms of movements and the results 

 of movements, inasmuch as these signs are capable 

 of observation and experimental inquiry. I cannot 

 tell what results may come from such work, but, 

 as previously said, it was undertaken with the 

 desire to determine what forces are necessary to aid 

 brain development, such as is necessary to the 

 mental and moral evolution of the child. 



