MOTOR FUNCTIONS OF CEREBRAL CORTEX OF CAT 181 



the stimulus to be employed in each case is the degree of definite and 

 decided localization of effects uniformly obtainable. 



The results of Ferrier's experiments may be summarized as 

 follows: Stimulation of the median area the posterior portion 

 of the sigmoid gyrus is followed by movements of the hind 

 limb; stimulation of the region immediately anterior to the 

 posterior extremity of the coronal fissure, by movements of the 

 fore limb; stimulation of the area immediately internal to the 

 anterior extremity of the coronal fissure, by movements of the 



FIG. 3. Motor areas of the cat's cerebrum, determined by Ferrier (adapted). 

 1, advance of the hind leg; 4, retraction and adduction of the fore leg; 5, ele- 

 vation of the shoulder, flexion of the fore arm and paw, sometimes clutching or 

 grasping action of the paw, with protrusion of the claws; 7, elevation of the 

 angle of the mouth and cheek, with closure of the eye; 8, retraction with some 

 degree of elevation of the angle of the mouth, and drawing downward and for- 

 ward of the ear; 9, opening of the mouth and movements of j the tongue.; 18, eye- 

 balls moved to the opposite side; 14, pricking of the ear and eyes turned to the 

 opposite side; IS, elevation of the lip and torsion of the nostril on the same 

 side; 16, divergence of the lips. 



fore limb and shoulder. Of the remaining lateral and superior 

 regions of the cortical surface, stimulation of that portion, lying 

 between the posterior halves of the lateral and the supra-Sylvian 

 fissures, results in movements of the eyes and head. Stimula- 

 tion of the region adjacent to the anterior extremity of the 

 supra-Sylvian and extending to the coronal fissure results in 

 movements of the mouth, tongue, lips, ear and paw. It is in- 

 teresting to compare the results with those obtained in the 

 present work. For purposes of comparison a diagram of Fer- 

 rier's localizations is here given (fig. 3). 



