Long-term interference effect: An alternative to learned helplessness.

Abstract

This article presents three experiments that explore whether inescapable shock of long duration and moderate intensity (LoShk) produces an avoidance-escape deficit (called an interference effect) by causing animals to learn to respond less actively or by causing them to learn to be "helpless."The first experiment showed that if animals given LoShk were subsequently tested in an avoidance-escape "nosing" response that required little motor activity, they learned and performed better than no-shock controls. The second experiment verified that the same LoShk treatment that led to this better performance in the first experiment would indeed interfere with subsequent avoidance-escape acquisition in those test situations that have previously been used to demonstrate the interference effect, that is, the three-response lever press, two-response shuttle, and single-response barrier jump. Finally, in the third experiment, using triplets in the classical avoidance-escape, yoked, and control animal paradigm, it was shown that yoked animals performed more poorly than either avoidance-escape or control animals on a subsequent three-response lever-press task but performed better on the nosing avoidanceescape task that required little movement. The results are interpreted as being compatible with the idea that animals acquire the tendency to be inactive as a result of exposure to long-duration, moderate-intensity, inescapable shock. The results are seen as incompatible with the idea that animals learn "helplessness," that is, not to associate behavior with its consequences, as a result of exposure to such shock.In a preceding article , it was shown that what is called the "interference effect," that is, the disruption of avoidance-escape behavior by prior exposure to inescapable shock, occurs in at least two different ways. The first type of interference effect follows a single session of high-intensity, inescapable shock, and this deficit dissipates relatively rapidly over time. It is our contention that the original work done on the interference effect (Overmier & Selig-

Adaptive Behavior and Learning

“…These two characteristics define the phenomenon known as learned helplessness. In the original experiment (Seligman & Maier, 1967; for reviews see Maier & Jackson, 1979, Alloy & Seligman, 1979and Glazer & Weiss, 1976) dogs were first restrained in a harness and given a series of severe, inescapable shocks. The next day, they were placed in a simple discriminated avoid-ance situation: in each trial, when a CS came on, shock followed after ten seconds unless the dogs jumped over a low barrier.…”

Loss of controllability in appetitive situations interferes with subsequent learning in aversive situations

“…It hasbeen termed the leamed helplessness effect (Seligman, 1975) or the interference effect (Glazer & Weiss, 1976a, 1976b. The learned helplessness theory (Maier & Seligman, 1976;Seligman, 1975) explains that this effect arises from the leaming of uncontrollability-that outcomes are independent of responses.…”

Time-dependent exacerbation of amphetamine-induced taste aversions following exposure to footshock

“…However, stressor-induced al terations in avoidance behavior are not always evident immediately following exposure to stressors. For exam ple, inescapable footshock produces deficits in shuttle escape performance 24-72 h after exposure to shock but escape deficits are typically not evident immediately fol lowing shock (Anisman 1975;Glazer and Weiss 1976;Anisman et al 1978;Prince and Anisman 1984). It is therefore possible that footshock can alter amphetamine-CTA but only when footshock precedes saccharin-am phetamine pairing by 24-72 h. Experiment 2 was con ducted to evaluate the impact of exposure to footshock a number of days prior to saccharin-amphetamine pair-T ab le 1 M ean (±SEM) water consumption values (ml) on days prior to (Baseline) and between saccharin consumption tests for the four treatment groups.…”

“…It is not clear why the facilitation of amphetamine-CTA is not evident when shock is applied between saccharin consumption and amphetamine injec tions but there are other examples of the delayed effects of stressors on avoidance responses. For example, stressinduced deficits in shuttle escape responding are typical ly not evident immediately following stressor exposure but are evident 24 or 48 h later (Anisman 1975;Glazer and Weiss 1976;Anisman et al 1978;Prince and Anis man 1984;Anisman and Zacharko 1988). Studies exam ining cross-sensitization between stressors and stimu lants like amphetamine have also shown that cross-sensi tization usually requires a delay between stressor expo sure and stimulant exposure (Ante]man et al 1983;Rob inson and Becker 1986).…”