TRANSFER OF RESPONSE IN THE WHITE RAT 27 



for punishment were located just to the left of the keys 

 (K and K') used for working the sounders. The method of 

 procedure had regularly been to use the left hand for working 

 the 'sounder' keys and the right for opening and closing the 

 doors of the box whenever necessary and for handling the 

 animal. To have the left hand free to work the 'sounder' 

 keys the right was also used to work the 'punishment' keys 

 whenever necessary. The various movements made by 

 the experimenter were usually as follows: The left hand 

 remained resting at the 'sounding' keys while the right was 

 used in adjusting the return doors (RD and R'D' in figure 

 I) and in putting the animal into the entrance alley (EA). 

 Then the proper 'sounder' key was manipulated by the left 

 hand and the sound stimulus given until a choice had been 

 made, the right hand in the meanwhile resting upon the edge 

 of the box. If a wrong choice had been made the sound was 

 discontinued and the right hand was stretched across to the 

 'punishment' key and punishment given. In case of the 

 animals mentioned above as showing evidence by the records 

 of learning the required response the experimenter became 

 convinced from observation of the general behavior that it 

 was this very evident motion of the right hand or perhaps 

 of his whole body that in some way served as a warning 

 when about to enter the wrong alley. So a change was 

 made in procedure. Instead of using the right hand for 

 pressing the 'punishment' key, the right hand was allowed 

 to remain lying on the edge of the box and the left was 

 slipped as unobtrusively as possible from the position of the 

 'sounder' keys to that of the 'punishment' keys. A com- 

 parison of the records for five series before this change was 

 made and for five series after the change was made will be 

 surprising. Practically every animal which gave evidence 

 that the response was being learned showed a considerable 

 decrease in efficiency of response after this change was 

 made. For the sake of comparison I have gathered them 

 together in the following table: 



