THE CORTEX 309 



Certain well-defined qualities of taste are recognised — 

 salt, bitter, sweet, sour, alkaline, metallic. Some so-called 

 tastes are in reality a combination of true taste sensation 

 with smell and common sensation. 



5.— MOTOR FUNCTIONS OF THE COKTEX 



Having described the different sensations which play upon 

 the cerebrum, we may now consider the motor aspect of this 

 part of the central nervous system. Although the relation- 

 ship between the cerebrum and the skeletal muscles had 

 long been known from clinical experience and histological 

 investigation and particularly from the work of Hugh- 

 hngs Jackson, it remained to Fritsch and Hitzig, in 

 1870, to demonstrate the connection experimentally. This 

 pioneer work was afterwards amphfied by many workers, 

 particularly those of this country, Ferrier, Horsley, Schafer, 

 Bastian, Sherrington and 'others. The principal part of 

 the brain concerned in movement is the strip which hes 

 immediately anterior to the Rolandic or central fissure (the 

 precentral or motor area). Here all parts of the body are 

 represented in order, from the toes near the middle line 

 to the face laterally. An area on the third frontal con- 

 volution is concerned in conjugate movement of the eyes 

 to the opposite side (Fig. 55). 



The movements which are evoked by stimulation of any 

 part of this area are confined to the opposite side of the 

 body, except in the case of those movements in which 

 muscles of both sides of the body normally take part, 

 such as movement of the eyes, jaw and trunk. The move- 

 ments are always co-ordinated and involve reciprocal action 

 of antagonistic muscles. 



When the motor area of one side is removed in the 

 monkey the resulting paralysis is followed by a certain 

 degree of recovery, but there is a permanent loss of finer 

 accurate movements. The recovery is not due to education 



