REDINTEGRATION IN ALBINO RAT— A STUDY IN RETENTION 7 



This has been estabHshed by experimentation in this work. 

 If fewer than six perfect trials are regarded as the norm, 

 additional trials are likely to reveal the imperfection of 

 response. The rat thus was required to run the last nine 

 trials, whether perfect or not. The majority of these last 

 trials were generally perfect, according to the norm of the 

 first six. In the foreging the word, " integrations," is to be 

 understood as meaning an absence of so-called " errors," 

 or imperfect movements. Thus, if a rat exhibited perfect 

 movements in making a turn from one alley into the next 

 these movements were considered perfectly integrated, ir- 

 respective of speed and hesitations. The employment of 

 the camera lucida denied any further determination, as 

 regards details of the method by which the animals learned 

 the problem. 



All criteria of learning in the maze have been based on 

 these three — time, " error," and distance. In deciding on 

 a norm for the present work, the time and distance criteria 

 have both been eliminated to a certain extent because 

 they were considered as only minor factors in aiding the 

 pointing out of essentials in learning and retention. The 

 learning of the maze consists in the acquirement by the 

 rat of certain integrated movements; and the trials after 

 the period of disuse of these movements shows the loss in 

 integrations of movements, if any. Time and distance as 

 primary factors can not be employed except under almost 

 impossible conditions to show what actually takes place 

 in the learning of the maze, but they are valuable as sec- 

 ondary factors. The primary criterion for us has thus 

 resolved itself to one of movement, and therefore precision 

 of integration is primarily concerned. , " Error," therefore 

 will not be considered except in the sense of imperfect 

 integration. 



There has never been any definite agreement as to what 

 may be adjudged an " error." Not considering hesitation, 

 an " error " may be said to have been made by the rat 

 when, in the process of solving the problem, it enters a 

 cul-de-sac or retraces its steps. Here is where distance as 

 well as time may enter as factors, and they do so every 

 time an " error " is made. But they are eliminated as 



