PERSEVERANCE REACTIONS IN PRIMATES AND RODENTS 31 



a single reaction of this type with the exception of a fifteen-year 

 old boy who, in a moment of embarrassment reentered an alley 

 that he had just tried unsuccessfully. In the present studies 

 only the two three-year old girls and two temperamental five- 

 year old girls of a total of 20 human subjects exceeded the group 

 average of two E-reactions per 100 trials. The individual records 

 of the 24 rodents, on the other hand, disclose a minimum of 12 

 such reactions per 100 trials for any individual and a maximum 

 of 53. 



2. Excitability. — When a subject is directing his activities 

 toward adjustment to a situation which has initiated reaction 

 the repetitive tendency is favored by the concurrence of adjus- 

 tive reactions and strong emotional reactions. Even the average 

 human adult, if trapped and badly frightened in a burning hotel, 

 will rush madly again and again to a part of the building which 

 obviously will not afford escape from the building, thereby divert- 

 ing time and effort from as yet untried possibilities of escape 

 which would readily occur to him if he were not excited. An 

 angry man will stupidly repeat an empty phrase instead of 

 varying his efforts to effect a verbal adjustment to the situation. 

 If now, any subject, either human or infra-human, is easily excited 

 by a situation which elicits reaction by failure to effect a ready 

 adjustment to it or by intercurrent or adventitious stimuli, he 

 is more apt to manifest reactions of the primitive D and E 

 types than is the subject whose affective responses to such con- 

 ditions are of less intensity. 



3. Distractibility. — Among primates and, to a certain extent, 

 among infra-primate mammalians one is apt to encounter more 

 or less marked individual differences of capacity for sustained 

 exclusive responsiveness to an unexciting situation which precipi- 

 tates adjustive reaction thereto. Distractibility consists in a 

 tendency toward quick shifts of responsiveness from possible 

 stimulus to possible stimulus, with consequent absence of sus- 

 tained responsiveness to a particular stimulus. When a stimu- 

 lus or stimulus-complex S-1 leads to adjustive activities, and 

 intercurrent stimuli S-2, S-3, etc., cause an incomplete shifting 

 of responsiveness from S-1 to S-2, S-3, etc., so that activities 

 directed toward adjustment to S-1 do not wholly cease, we may 

 expect the subject to manifest reactions of the D or E type. 



