INTEGRATION OF MOVEMENTS IN LEARNING IN THE RAT 425 



trials, particularly in the first few. There is developed, or better 

 facilitated, at these trials, direct progression to the door of the latch- 

 box problem from the entrance box. A great many rats were 

 observed during the facilitation of direct progression and the 

 production of posture, and these two movements though previ- 

 ously coordinated were now by training bettered for the produc- 

 tion of the neck reflex movement. An appropriate term for the 

 improved performance of these two movements was thought 

 desirable, and the term directive integration was adopted. The 

 development of directive integration may be expressed by saying 

 direct progression and posturing have been facilitated for the 

 production of the neck reflex. 



In most cases, before directive integration is facilitated, many 

 movements are more effectively directed to the door of the prob- 

 lem box. The most noticeable external sense which aids direct 

 progression to the door is vision; for, on the second or third trial, 

 progression is, with the aid of vision, direct to the door. In 

 some cases when directive integration is slow in being facilitated, 

 the latch is for some time located by touch. As soon as progres- 

 sion to the latch is facilitated and posturing is bettered, apparently 

 no definite external sense aids progression to the latch. The fa- 

 cilitation of direct progression with the production of posture 

 apparently comes about through the development of an interac- 

 tion of bddy parts of the rat, rather than through the establish- 

 ment of "sensory association." 



In the first few trials with the facilitation of directive integra- 

 tion, the greatest change that occurs is not in the production of 

 the neck reflex but in all the integrated movements that are 

 auxiliary to it. The introduction of vision is one progressive 

 step in the development of interaction for the facilitation of di- 

 rective integration and the attainment of posture. The change 

 is particularly noticeable in those rats in which the reflex thrusts 

 are functionally the best. Very few movements in the second 

 and a few succeeding trials occur before the production of pos- 

 ture under the latch, and the neck reflex is produced much more 

 readily. With other rats numerous movements are still made. 

 Posturing is excessive and relaxation from such a position with 



PSTCHOBIOLOGT, VOL. II, NO. 5 



