| Abstract: | Compared characteristics of T-maze alternation behavior by giving 11 hooded rats 7 sessions under conditions of "rerun correction" (contingent reinforcement for alternation) and another 11 Ss the same number of sessions with noncontingent reinforcements (i.e., entering either goal arm of the –T maze was reinforced). Both groups alternated significantly above chance, and the difference in medians between groups was small but significant. However, Ss given rerun correction training quickly came against the "ceiling" of 100% alternation, and individual differences were small. Scores of Ss run under conditions of "spontaneous" alternation were more variable, both within and between Ss. In a 2nd part of the study, 6 Ss in each group received small electrolytic lesions in posterodorsal septum. There were 5 operated-control Ss from each group. After 2-wk recovery all Ss were again given 7 sessions in the –T maze. Under rerun correction procedure, controls retained near-perfect alternation scores. Most Ss with lesions dropped to chance levels but recovered to control level over the sessions. Ss tested under spontaneous alternation conditions behaved quite differently. Controls continued to alternate significantly, but Ss with lesions alternated significantly less and did not recover. (14 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
