Fig. 8.
Long-lasting effects of the contingent reinforcement. During a 10 min test period that began 1 hr after the training session, the contingent-reinforcement group (black bar) expressed a significantly greater number of occurrences of the reinforced pattern (pattern I, A), but not of the nonreinforced patterns (pattern II and intermediate, B), than in the control (white bar;p < 0.001) and the yoke-control groups (gray bar; p < 0.05). The effects of the contingent reinforcement persisted for >1 hr. Five nondesheathed preparations in each group were used.