62 WALTER S. HUNTER 



of delay go, F ranks approximately half way between the other 

 children and the raccoons. As to apparent method of work 

 she — and the other children too — is superior to the raccoons in 

 that orientation played no discernible role in her reactions. 



VI. THEORETICAL CONSIDERATIONS 

 1. The Cues Essential for Successful Delayed Reactions 



After the above presentation of experimental results, there 

 remains the important task of determining as nearly as possible 

 just what cues the subjects used in their reactions. The follow- 

 ing paragraphs of this section will set forth in detail the various 

 possibilities of interpretation and indicate what seem to me to 

 be their relative validities. 



Let us first formulate in a general way the conditions that a 

 reagent will have to meet in the solution of the present problem. 

 He is confronted with three boxes which offer as many known 

 possible points of egress. One of the boxes is lighted. In the 

 course of a series of experiments, the reagent has learned to go 

 through, or to the lighted box in order to reach food. In time 

 the stimulus will set off the reaction practically automatically. 

 Approximately at this period, I begin to turn oft' the light before 

 the subject reaches the box. It is possible that for several 

 stages of delay the box which has been lighted remains light 

 for a short interval of time due to the presence of after-images 

 in the subject's eyes. But as the delays increase in length, there 

 will come a point at which the problem shifts from "go to the 

 lighted box" to "go to the one of three dark boxes that was 

 most recently lighted." If this shift comes before the i sec. 

 delay, it will be less likely to involve relearning. If, e.g., the 

 change comes at the second stage, the momentum of running 

 will make it easier for the animal to continue into the dark 

 box than to turn and seek another. With some rats, the results 

 indicate that the change did come at this stage ; for when the 

 light was turned out, the animals stopped short and went into 

 another box, even though that too was dark. With the other 

 animals and the children, it was impossible to tell just when 

 the shift came. The problem having once changed, however, 

 the question now is how long after the boxes all become dark 

 can the subject pick out the one which was lighted most re- 

 cently. Our special problem concerns only the solution of this 



