In two experiments, we examined whether or not a loss of control over food availability would interfere with subsequent two-way shuttle-escape learning. Rats that had experienced loss of control over food delivery were impaired in their acquisition of a shuttle-escape response, relative to the response-contingent and the continuous-reinforcement control rats (in Experiments 1 and 2) and to the lack-of-control and home cage control rats (in Experiment 2). Rats that had received noncontingent food delivery without a prior history of control over food exhibited poorer performance than did the home cage control rats. Moreover, loss of control resulted in a larger interference effect than did lack of control, supporting the view that the learning of response-outcome noncontingency is the main determinant of the interference effect.

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The present study examined whether or not a loss of control over food acquisition would interfere with disk pulling shock escape learning. The loss-of-control rats, which had experienced loss of control over food delivery, and the lack-of-control rats, which had received noncontingent food delivery without a prior history of control over food, were impaired on acquisition of the fixed ratio (FR) 2 disk-pull escape compared to the response-contingent, the continuous-reinforcement (CRF)-control, and the home-cage-control rats, which did not differ from each other. These findings support the view that the learning of response-outcome noncontingency produces a subsequent helplessness phenomenon, in a proactive fashion.

The present experiment examined whether or not predictability over food acquisition eliminated the impairment of subsequent escape performance which otherwise resulted from loss of control over food acquisition. For the predictable/controllable (P/C) and the yoked predictable/uncontrollable (P/UC) groups, given a required response by the P/C rats during pretreatment, a 1.5-s tone was followed by food, For the unpredictable /controllable (UP/C) and the yoked unpredictable/uncontrollable (UP/UC) groups, the tone was randomly presented during pretreatment. Results of the number of failures on the disk-pull shock-escape test indicated that the P/UC group showed the same superior performance as the P/C, UP/ C, and naive control groups, which differed significantly from the UP/UC group. This modulating effect of a predictive signal is hypothesized to be due to an overshadowing of predictability upon uncontrollability.