MOTOR FUNCTIONS OF CEREBRAL CORTEX OF CAT 213 



by stimulation of the seven hemispheres. No attempt has been 

 made to present the average field or to indicate the differences 

 in the animals, which in this respect were very great. 



The results of these tests may be compared with the results 

 reported by Ferrier. It is seen that there is considerable simi- 

 larity in the two series of results. For example, the field for 

 the eye movements is almost coextensive in the two diagrams. 

 Movements of the face region are from an area similarly located 

 in the diagrams, immediately external to the anterior portion 

 of the lateral fissure, though considerably more extensive accord- 

 ing to Ferrier than is indicated by the present results. Ferrier's 

 results from stimulation of the true motor region are, so far as 

 they are given, identical with those here obtained. 



Of the regions here referred to as " extra-motor," that lying 

 adjacent to and between the longitudinal portion of the lateral 

 and supra-Sylvian fissures give movements of the eyes in both 

 Ferrier's and my experiments. Certain movements of respira- 

 tion, which are found from stimulation of the banks of the supra- 

 Sylvian region, are not mentioned by Ferrier. In both series, 

 the region lying between the posterior portion of the coronal 

 fissure and the anterior extremity of the supra-Sylvian fissure 

 gives movements of the face area. Ferrier obtained no move- 

 ments of the hind limb from the region external to the posterior 

 portion of the coronal fissure, while in the present series of ex- 

 periments such responses were frequently obtained. Ferrier 

 secured a very extensive exposure of Sylvian area, and obtained 

 motor responses of the lips, mouth and nose by stimulation in 

 that region. No attempt was made in my experiments to ex- 

 pose this region and consequently a comparison cannot be 

 made other than to say that the extra-motor field for these 

 movements ran from the coronal fissure outward in such a di- 

 rection that if further exposure had been made it seems probable 

 that Ferrier's results would have been confirmed. 



The probable reason for the consideration of these areas as 

 truly motor by Ferrier, was his failure to recognize and distin- 

 guish between what we believe, as a result of careful and more 

 recent histological and physiological methods, is a true motor 



