210 JOSEPH DUERSON STOUT 



frequent combination of such types of movement in the produc- 

 tion of certain forms of activity, which are in constant demand in 

 the individual's reaction to his complex environment. 



ANALYSIS OF THE RESULTS OBTAINED FROM STIMULATION OF THE 

 EXTRA-MOTOR CORTEX 



In each of the animals studied investigation was made of 

 results of irritations of other portions of the cerebral cortex, 

 lying outside of the boundaries of what we believe to be the true 

 motor field. These extra-motor fields are the readily approached 

 anterior, superior and lateral aspects. It was found that usually 

 there was no response from stimulation with the ordinary strength 

 of current for a moderate time. With an increased strength of 

 current, or with an application for a longer time, a total of fifty- 

 nine responses was obtained. From study of these the following 

 observations are made: 



1. A stronger current or longer application was required than 

 for stimulation of the motor cortex. 



2. The latent period of the movement, when a movement was 

 obtained, was always longer than for cortical motor stimulation. 

 Frequently the latent period was three or four times as long as 

 that of movements resulting from the stimulation of the "pri- 

 mary" motor cortex. 



3. As far as inspection could determine, the movements which 

 were produced were as functionally perfect as were movements 

 produced by stimulation of the motor cortex. 



4. The movements involved more restricted portions of the 

 body musculature than did movements from motor cortex stim- 

 ulation, and they frequently were of a so-called vegetative nature, 

 that is they involved mechanisms whose activities are for the 

 carrying on of respiration, or jaw and tongue movements, such 

 as are encountered in mastication. 



5. When analysed, the fifty-nine responses were found to 

 include a total of seventy-three simple movements, of which 

 only twenty-eight involved the contra-lateral side of the body 

 alone, one the homolateral side alone, and thirty-four involved 



