587 



the signals. This can only be indicative of a high state of 

 excitement and emotional disturbance in the experimental 

 situation. 



Generalisation. The term generalization is used here to 

 designate the tendency to respond to signals other than the 

 particular one used in training the animal. In the motor 

 reflex, as in the salivary, the dogs of group A did not respond 

 to all signals introduced. This is shown in column 8 of table 

 7, in which a plus sign indicates those dogs which reacted 

 to all additional signals, while a minus sign designates those 

 which did not. The dogs of group B responded to every 

 signal presented, no matter how much it differed from the 

 one used in the initial training. Kymographic records of 

 the generalized responses of the extreme types to a bell are 

 shown in text-figure 103 (figs. 1 and 2). Note that type A 

 was not disturbed by the bell, while type B gave vigorous 

 head movements as well as leg reactions. 



Because of the wide generalization in the excitable animals, 

 it was extremely difficult to develop a negative reaction, and 

 in fact in most of them, impossible. Since the foreleg was 

 raised in response to any signal given, it was evident that 

 in order to form a negative it would be necessary to intro- 

 duce a different reaction. This reaction had to be one which 

 necessitated lowering the foreleg. In one method, food was 

 presented with the negative signal. In order to take the 

 food, the dog had to shift the whole posture, lower the foreleg, 

 and step forward to the pan. This behavior, of course, would 

 give a negative leg reaction, that is, negative in regard to 

 its former positive avoiding position. It was thought that 

 if this procedure was repeated often enough, the dog might 

 learn to raise the leg when the signal for shock was given, 

 but approach the pans for food when the second signal was 

 given, and in this manner learn to differentiate between the 

 two. Even with this plan, however, responses showing dif- 

 ferentiation could be developed in very few dogs. Most dogs 

 would refuse the food. And those dogs that did learn to 

 respond to the two different signals in the desired manner 



