J. Bruce Overmier

Who they are

This page records the public professional record only. Nothing adverse is recorded and no motive is attributed.

The 1967 paper gives his affiliation as the University of Minnesota. The 2023 review places him earlier, as a senior student in Richard Solomon's laboratory at the University of Pennsylvania, alongside Russell Leaf, when the two found that dogs given earlier Pavlovian conditioning later failed to learn a simple escape. In that conditioning a tone was paired with footshock across 64 trials. The control dogs learned the escape easily, since they only had to jump a small hurdle to end the shock.

Nothing else about his career was checked for this page.

Key papers

Overmier, J. B., & Seligman, M. E. P. (1967). Effects of inescapable shock upon subsequent escape and avoidance responding. Journal of Comparative and Physiological Psychology, 63(1), 28-33. doi:10.1037/h0024166.

The paper has two sessions in each experiment. In the first, dogs received inescapable shock or none. About 24 hours later, in the second, they had 10 trials of escape-avoidance training in a shuttle box. The three experiments used 32, 24 and 32 dogs.

In the first experiment, four groups of eight were compared: no shock, 64 unsignalled five-second shocks, 640 brief shocks of half a second, and 64 brief shocks. All shocked groups were slower to escape and failed more often than unshocked dogs, and the shocked groups did not differ from one another.

In the second experiment, three groups of eight tested two alternatives. A group trained with a higher shock intensity of 6.5 milliamperes still showed the interference. Dogs paralysed with curare during the first session were slower than dogs paralysed without shock, so the interference did not depend on paralysis or on learned movements.

In the third experiment, eight groups of four were tested after delays of 24, 48, 72 or 144 hours. Those tested at 24 hours showed interference. Those tested at 48, 72 and 144 hours recovered and did not differ from unshocked controls. The authors concluded that the effect dissipates rapidly, leaving an apparently normal animal after only 48 hours.

Key ideas

The paper's central move is to separate shock from uncontrollability. By removing the tone used in the earlier conditioning and giving footshock alone, Overmier and Seligman found the later escape deficit persisted, and they suggested that "the source of the interference is a learned 'helplessness.'" The 2023 review credits them with the first use of the term.

The paper also reports the time course. The effect had gone by 48 hours in the third experiment. The 2023 review says the interference persisted for only two to three days, and links the transient effects to desensitisation of serotonin 1A receptors, which it says lasts a few days.

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