VISUAL PERCEPTION OF THE CHICK 95 



The maze habit was found to be measurable with reference 

 to approaches to (1) outside corners, (2) inside corners, and 

 (3) stimuli. Measurability of the discrimination habit was 

 based chiefly upon + and — choices, but certain quahtative 

 criteria were found to be highly suggestive of stages of learning. 



The method of punishment for wrong choices was found to 

 be both valuable and pernicious. If intelligently used, it 

 seems, on theoretical grounds at least, to be highly valuable; 

 if carelessly applied, punishment can radically interfere with 

 learning. It is my conclusion, although the present study 

 does not prove it, that the optimal shock is dependent more 

 upon the sensitiveness of the animal than upon the ease or 

 difficultness of discrimination. 



For adequate descriptions of animal behavior in problems 

 of discrimination, these results indicate that finer criteria than 

 right and wrong records should be seriously considered. Detailed 

 analysis of the behavior of No. 27 reveals, at least in one place, 

 evidence of discrimination that is not apparent from gross 

 records of right or wrong choices. Furthermore, the common 

 practice of presenting to many or to all subjects precisely 

 identical experimental conditions should be critically considered. 

 Evidently there is an optimal degree of punishment, for example, 

 which varies with individuals. It is desirable at least that 

 mass results be checked with intensive individual observations. 



