180 John B. Calhoun 



In those cages containing recently weaned young, the young soon scat- 

 tered the pile of objects, exposing the lever, and in so doing accidentally 

 pressed the lever and gradually learned its function. There then followed a 

 repeated process of covering the lever by the adults and its removal by the 

 young. Through this process the adults were forced to face E, represented 

 by the lever and its attached water reservoir, sufficiently to permit an A 

 adjustment to E thi-ough the DMA decline process. Several points may be 

 deduced from these observations. Th for the adults had previously drifted 

 downward toward b so that the E lever configuration caused DMA to 

 exceed it. Furthermore, at weaning Th is sufficiently removed from b that 

 many ^'s will fail to evoke DMA elevation above Th. Had evolution not 

 resulted in such a balance between neurology and physiology, animals just 

 emerging out into the many E's of their environment would immediately 

 be forced into a withdrawal state. Although I shall not go into this problem 

 here, it is obvious that retardation of "weaning" increases the probability 

 of withdrawal . 



In the three cages lacking recently weaned young, the pile of material 

 covering the levers remained undisturbed for several days until the rats 

 were so weak from lack of water that it was apparent that their rejection 

 of the lever was so complete that they would die before getting the op- 

 portunity to learn its function through chance depression of it. Replacing 

 the former water bottle merely satisfied their thirst but failed to alter their 

 rejection of E. "Teaching" the rats the lever was finally accomplished by 

 taking all movable objects from the cage and gradually increasing the 

 interval during which the water bottle was removed. It took 3 weeks to 

 reach the same level of lever pressing by these rats that was obtained within 

 3 days by adults when young not only made rejection impossible but also 

 set an example of adjusted interaction with the E lever configuration. 



Other examples of such d" active rejection, but toward social E's, have 

 already been given in Section XIII, B, 4 in connection with the three 

 examples involving Barnett's Norway rats, the "Freedom Riders," and 

 the formation of the Co7 Colony IB of house mice. Thus, in terms of active 

 rejection, d" becomes essentially synonymous with intensity of action 

 tow^ard another, i'-^f as given by Eq. (114). But d" must also encompass 

 the more strictly psychological phenomena of psychological deafness or 

 psychological blindness such as characterizes the "malingering type" of 

 individual. 



Note that this consideration of exploratory behavior has lead to formu- 

 lations of d", v", and A". As for prior comparable terms: 



/' = (d"v"/A") (127) 



Here /x" represents a third contact modifying function when relating to 



