INTEGRATION OF MOVEMENTS IN LEARNING IN THE RAT 391 



animals accustomed to an environment. If this small amount 

 of epinephrin in glands is indicative of the existence of reflex ex- 

 citability, the latter might be expected to accompany such be- 

 havior as noted in rats in a new environment. To say that the 

 sensory impressions received and that the responses that follow, 

 are "to familiarize the rat" with a new situation, is to express 

 inadequately the significant changes that must take place in the 

 organism. It is important to correlate these changes with those 

 observed when a rat is for the second and third time admitted 

 to the problem. Both the organic changes that can be said to 

 take place and the gross movements performed have but one 

 effect; they seem to fit the organism for any new change that may 

 occur in the environment. Learning has begun with the first 

 presentation of the problem. We have looked upon this period 

 of preliminary feeding as one of preparation, and have not re- 

 garded it as having a cumulative effect on the organism to meet 

 any additional change in the environment of the problem, such 

 as shutting and fastening the door. 



When the door of the latch box problem is closed, movements 

 are more strikingly confined to the problem box, particularly to 

 the door. In some rats activity is greatly augmented, but in 

 others no perceptible increase can be detected. When activity 

 is increased, it appears to be conditioned either, because the pas- 

 sage to the food through the door can not be made, or because the 

 odor of food increases general activity. Progression then is 

 here and there with the production of many common acts. 

 These acts may be completely, partially, or incompletely pro- 

 duced. The common acts completely performed are those which 

 are generally and effectivly performed, such as crouching of the 

 body, climbing, and even at times playing. These movements 

 are inherently conjoined or coordinated, not newly conjoined 

 nor is any one of them modified to constitute a new or a complex 

 movement. One kind of inherent fundamental movement passes 

 to the other in a definite order. Climbing may be followed by 

 running, progression may end in crouching or moving things about 

 by an upward movement of the head, or pushing the snout into 

 the wire mesh of the problem box or into the hood which covers 



