R. W. DOTY AND C. GIURGEA 

 Table I 



INITIAL FAILURE OF DIFFERENTIATION IN DOG EPSILON 



139 



Stiiuiiliis location Total differentiation trials 



LFL CRs RFL 'CRs' 



R-CS, R-US 

 L-CS, no US 



50 

 44 



14 



for twelve sessions with results as shown in Table I. Obviously no differen- 

 tiation occurred under these conditions; CRs were maintained to stimula- 

 tion of cither area though the percentage of occurrence to R-CS may have 

 declined. 



Fig. 3 

 One of the first conditioned responses of Dog Epsilon to stimulation of right marginal gyrus. 

 At this time the CR is in the 'wrong' leg, but in subsequent trials the left foreleg, the one lifted 

 to the US, lifted to this CS (Doty, 1959). 



It is characteristic of these animals (Giurgea, 1953 a, b) that just prior to 

 the appearance of the first CRs and frequently thereafter, movements of 

 the affected limb occur sporadically during the intertrial period. This 

 phenomenon was observed in Dogs Beta and Epsilon. These movements 



