Abstract
It is a general tendency that a partial reinforcement effect (PRE) is not found in the fish. However, there are some evidences that nonreinforcement influenced learning and extinction process. The present experiment, was conducted to investigate the effects of nonreinforcement on resistance to extinction of the fish under high reward magnitude. In addition, the effect of overtraining on extinction was investigated.
24 goldfish were trained and extinguished with massed trials in the alley-type apparatus. In the E group, 24 successive nonreward trials were interpolated into the total of 69 acquisition trials (consequently, the E received 65% partial reinforcement). The C group received 100% continuous reinforcement (see the under part of Fig. 1).
The E was less resistant than the C, and PRE was not obtained in terms of between-groups (Fig. 1) and of within-group (Fig. 2 (A)). Overtraining did not facilitate the extinction of the C group (Fig. 2 (B)). These results indicate that resistance to extinction depends on the habit strength which increased as a function of number of reward trials, and suggest that the aftereffect of nonreinforcement has not a positive effect to control the behavior of fish.
