| Abstract: | Rats received food following lever-press durations between t and t+t′ sec where t was 2, 4, or 8 sec and t′ was 0.25t, 0.50t, or 1.00t sec. Modal press durations were greater than t but less than t+t′ in all cases. Distributions of press durations were lower and broader for larger values of t. Lower t′/t ratios produced lower median press durations and relatively narrower press-duration distributions. Median press duration was a power function of t within a t′/t ratio condition, corresponding to previous results for latency, interresponse time, and response durations. |
