THE CEREBRUM. 



129 



which the speech is affected, as compared with a left hemiplegia 

 and speech unaffected, this crossed action is impressed when we 



FIG. 36. 



Brain of Monkey, showing the position of the motor and sensory centres as ascertained 

 by Ferrier. The actions all occur on the side of the body opposite to the part of the 

 brain irritated : 1, the eyes open widely, the pupils dilate, and head and eyes turn to- 

 ward opposite side ; 2, extension forward of the opposite arm and hand, as if to reach 

 something in front ; 3, movements of tail (and trunk) ; 4, retraction with adduction of 

 opposite arm ; 5, supiiuition and flexion of the forearm, by which the arm is raised to- 

 ward the mouth ; fi, action of zygomatics, by which the angle of mouth is retracted and 

 elevated ; 7, elevation of ala of nose and upper lip ; 8, opening of mouth with protrusion 

 of tongue ; 9, retraction of tongue ; 10, retraction of opposite angle of mouth ; a, b, c, d, 

 prehensile movements; 11, retraction and adduction of opposite arm ; 12, advance of 

 the opposite hind limb; 18, complex movements of thigh, leg, and foot; 14, 15, vision 

 (sensory); 16, hearing (sensory). 



remember the localization of the centre for speech in the left 

 hemisphere near the motor area. 



Mention some of the common terms used in defining paralysis. 



Anaesthesia = loss of sensation. ^ 



Hemianaesthesia = loss of sensation in one lateral half of the 

 body. 



Hemiplegia = loss of muscular power in one lateral half of the 

 body. 



Paraplegia = symmetrical loss of muscular power in the lower 

 portion of the body and extremities. 



9 Phy. 



