PERSEVERANCE REACTIONS IN PRIMATES AND RODENTS 45 



the feeble-minded cases are excluded. If the two atypical mon- 

 keys are excluded the infra-primate group has the next highest 

 average number of C-reactions. Among rodents (the mouse 

 being excluded) the white-rat group has the highest average of 

 these reactions. 



6. The group averages of D-reactions (table 6) do not suf- 

 ficiently differ from one another to be of much significance, 

 since these averages were much affected by extreme individual 

 cases. 



7. In spite of the influence of atypical cases on the primate 

 averages for E-reactions, table 7 shows that the tendency toward 

 the manifestation of these reactions is much more marked among 

 rodents than among primates. The infra-human primate aver- 

 age number of E-reactions is conspicuously higher than the girl's 

 average number, but conspicuously lower than any rodent group's 

 average. 



8. The following factors favor the manifestation of Type D 

 and, particularly, of Type E reactions: 



(a) Inherent primitiveness of reactive equipment, such as is 

 possessed by rodent species and by the young or mentally defec- 

 tive of more highly developed species. 



(b) Excitability. 



(c) Distractibility. 



(d) Feeble responsiveness to a situation which elicits reaction. 



9. The first direction that is given to a subject's activities 

 under conditions which elicit escape responses is apt to be de- 

 termined by such factors as the spacial relations of the various 

 apparently possible avenues of escape, the recency with which 

 each of these various avenues have been previously tried for 

 escape and the frequency with which each has been previously 

 tried for escape. 



10. Recency and frequency, in the sense in which they are 

 used by Watson (7) are apt to be in themselves factors in deter- 

 mining the direction of a subject's activity, but when either of 

 these factors repeatedly operates advantageously it is apt to 

 act more strongly as a behavior determinant than where either no 

 constant advantage or actual disadvantage attend its operation. 



11. A comparison of the studies made under conditions which 

 operate against habit formation with those which favor habit 

 formation suggests that a response which has been frequently 



