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Martin Seligman's foundational experiments and theory of learned helplessness began at the University of Pennsylvania in 1965, as an extension of his interest in depression, when, at first quite by accident, Seligman and colleagues discovered a result of conditioning of dogs that was opposite to what B.F. Skinner's behaviorism would have predicted. A dog that had earlier been repeatedly conditioned to associate a sound with electric shocks did not try (later in another setting) to escape the electric shocks, even though all the dog would have had to do is jump over a low divider. The dog didn't even try to avoid the "negative stimulus"; the dog had previously "learned" that nothing it did mattered.
A follow-up experiment involved three dogs affixed in harnesses. The first dog was simply put in the harness for a period of time and later released. The second dog was put in the harness, and given electric shocks, which the dog could end by pressing a lever. The third dog was wired in parallel with the second dog, receiving shocks of identical intensity and duration, but his lever didn't do anything. The first and second dogs quickly recovered from the experience, but the third dog learned to be helpless, and suffered chronic symptoms of clinical depression.
A slightly different experiment was conducted where 2 groups of dogs were put in hammocks. One group was given shocks and were able to make them stop, the other group was unable to stop them. Later they were put in a room that was divided in half by a low barrier. One group of dogs were given electric shocks and jumped over the barrier to escape. The other group were given shocks, but as they had "learned helplessness" from the previous experiment, they just lay down and whined, and even though they could have escaped the shocks, they didn't try. Other experiments were performed with different animals with similar results. In all cases, the strongest predictor of a depressive response was lack of control over the negative stimulus.
A similar experiment was done with people performing mental tasks in the presence of distracting noise. If the person had a switch that would turn off the noise, his performance improved, even though he rarely bothered to turn off the noise. Simply being aware of the ability to do so was enough to substantially counteract its distracting effect.
Not all of the dogs in Seligman's experiments, however, became helpless. Of the roughly 150 dogs in experiments in the latter half of the sixties, about one-third did not become helpless, but instead somehow managed to find a way out of the unpleasant situation in spite of their past experience with it. The corresponding characteristic in humans has been found to correlate highly with optimism; however, not a naïve pollyanna optimism, but an explanatory style that views the situation as other than personal, pervasive, or permanent.
References & Bibliography
- Alloy, L.A. and Seligman, M.E.P. (1979). On the cognitive component of learned helplessness in animals and man. In G. Bower (Ed.), The Psychology of Learning and Motivation. New York: Academic Press, 219-276.
- Altenor, A., Volpicelli, J.R. and Seligman, M.E.P. (1979). Debilitated shock escape if produced by both short- and long-duration inescapable shock: Learned helplessness vs. learned inactivity. Bulletin of the Psychonomic Society, 14, 337-339.
- Garber, J., Fencil-Morse, E., Rosellini, R.A. and Seligman, M.E.P. (1979). Inescapable shock as a weanling impairs adult discrimination learning. Behaviour Research and Therapy, 17, 197-206.
- Hannum, R.D., Rosellini, R.A., and Seligman, M.E.P. (1976). Retention of learned helplessness and immunization in the rat from weaning to adulthood. Developmental Psychology, 12, 449-454.
- Rosellini, R.A. and Seligman, M.E.P. (1976). Failure to escape shock after repeated exposure to inescapable shock. Bulletin of the Psychonomic Society, 7, 251-253.
- Rosellini, R.A. and Seligman, M.E.P. (1978). Role of shock intensity in the learned helplessness paradigm. Animal Learning and Behavior, 6, 143-146.
- Seligman, M.E.P., Maier, S.F., and Geer, J. (1968). The alleviation of learned helplessness in dogs. Journal of Abnormal Psychology, 73, 256-262.
- Seligman, M.E.P. (1976). Learned helplessness and depression in animals and men. In J.T. Spence, R. Carson, and J. Thibaut (Eds.), Behavioral Approaches to Therapy. Morristown, N.J.: General Learning Press, 111-126.
- Seligman, M.E.P. and Beagley, G. (1975). Learned helplessness in the rat. Journal of Comparative and Physiological Psychology, 88, 534-541.
- Seligman, M.E.P., Rosellini, R.A., and Kozak, M.J. (1975). Learned helplessness in the rat: Time course, immunization and reversibility. Journal of Comparative and Physiological Psychology, 88, 542-547.
- Visintainer, M.A., Volpicelli, J.R., and Seligman, M.E.P. (1982). Tumor rejection in rats after inescapable or escapable shock. Science, 216, 437-439.
- Rosellini, R.A., Binik, Y.M., and Seligman, M.E.P. (1976). Sudden death in the laboratory rat. Psychosomatic Medicine, 38, 55-58.
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