No abstract

Rats were rewarded for running down a runway if the previous trial, over 16 min earlier , had terminated in a white plastic goalbox, but were not rewarded if the trial had terminated in a larger black wooden goalbox (or vice versa). Overall, the rats learned the discrimination, albeit poorly. There were six groups of two rats each; the factors were 0-, 10-, and 30-sec delays in the startbox and whether the black or white goalbox was S+. Discrimination learning occurred under each of these conditions and, contrary to concurrent interference theory, was not noticeably affected by startbox delay .