182 John B. Calhoun 



Regardless of the amount of prior opportunity to adjust to novel con- 

 figurations, the more intense £"48 elicited a more marked avoidance than 

 did Ei\. (See Section III, A, 3.) However, our present concern is with 

 a different aspect of the results in Table lib. 



I'pon exposure to EiA it appears that prior experiences with E^ was 

 much more effecti\'e than with E-i in reducing avoidance of the EiA con- 

 figuration. But members of both Groups B and C evinced much less 

 avoidance of Ei than did members of Clroup A. This supports the formula- 

 tion that prior opportunity to adjust to new configurations elevates Th 

 so that at a following exposure to another new configuration of stimuli, 

 DMA is less likely to exceed Th. Avoiding entering the alley is taken as 

 evidence of DMA exceeding Th. 



These results confirmed prior hypotheses. However, it was further as- 

 sumed that rats of Group D would exhibit the most marked accommoda- 

 tion to Ei since they would ha^-e had twice the opportunity for making 

 adjustments to new E's. And yet e\ei\ to E^a, the rats of Group D showed 

 little better capacity for adjustment than did members of Group B, and 

 much less than did rats of Group C. Upon elevation of the intensity of 

 Ei to EiB, members of Group D exhibited an extremely more marked reduc- 

 tion in capacity to adjust than did the rats of Groups B and C, that pre- 

 sumably had less opportunity for "training" in making adjustments. 



These results apparently contradict the theory. But consider the follow- 

 ing. For rats exposed to new configurations of stimuli, such as £"4, but 

 permitted to remain for several rather than for 2 hours, it has been noted 

 that many individuals reciuire up to 3 hours for DMA to decline to h. In 

 the 2000-odd tests where rats have been exposed to the AVtype alley con- 

 figuration to test for emotionality, the tacit assumption has been made 

 that the remaining decline in DMA will take place after the return of the 

 rats to their accustomed environment. However, this opportunity did not 

 prevail when, after 2 hours in E2 or E^, rats were transferred to the 

 opposite E. 



Events presumably transpiring are diagrammed in the left-hand side of 

 sketch (4) in Fig. 41. Upon exposure to Es after only partial decline of 

 DMA following exposure to E2, the same increment in DMA is elicited, 

 but its rise starts at the point of a still fairly high level of DAIA. Thus, 

 this second increment in DMA forces it above the threshold, Th, where 

 DjVIA is transformed from difi'use motor activity into the generalized stress 

 state, GSS. Although GSS and DMA were not measured during E3 (or 

 during E2, if it came second for Group D) , both must have eventually com- 

 pletely disappeared after the usual return to the home cage. And yet the 

 very failure of many members of Group D to enter the Ei alley when given 



