DURATION OF ANTECEDENT DISCRIMINATIVE STIMULI AND WITHIN-SUBJECT REWARD MAGNITUDE DIFFERENCES AS DETERMINERS OF RUNNING SPEED

5 groups of 8 naive Sprague-Dawley rats each received a total of 160 runway trials. In each block of 10 trials, 1 trial was to 20 pellets in 1 color runway and 9 trials were in the other runway for 5 pellets. Groups differed only in the duration (0, 3, 9, 27, or 81 sec.) of differential cues before the start-box door was opened. At asymptote all groups tended to run faster on the more frequent, small-reward trials. This difference decreased as duration of prestart cues increased. (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1969 American Psychological Association.