1979 年 50 巻 2 号 p. 97-101
A hypothesis was tested that the rate of learning in the rats exposed to inescapable tail shocks is reduced because of learned helplessness. Groups of eight rats were given 64, 48, 32, 16, or 0 inescapable preshocks, and then trained on an escape-avoidance task in a shuttle box for 5 fixed ratio (FR)-1 trials followed by 25 FR-2 trials. The latency for the shuttle response in the FR-2 trials was an increasing function of the number of inescapable preshocks. The findings support the hypothesis based on learned helplessness.