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Thesis (M.A.)—University of Nebraska—Lincoln, 1969. Department of Psychology.


Copyright 1969, the author. Used by permission.


The experiments investigated spontaneous recovery in an avoidance learning situation, using a modified one-way shuttlebox. In experiment I 60 male albino rats from the Sasco supply company learned the response of going from the shock side to the safe side in the one-way shuttlebox to the criterion of two successive avoidances.Extinction was initiated immediately after acquisition was complete. Three post-extinction delay periods were studied: 5 minutes, 1 hour, and 6 hours.Each subject was placed in either the shock or the safe compartment, and the latency to run to the opposite compartment was recorded.

Experiment II studied spontaneous recovery using the traditional measure, number of trials required to extinguish the response, in comparison with the number of trials required to re-extinguish it. The effect for extinction in experiment II was significant, as all subjects were resistant toward initial extinction; the delay effect did not reach a conventional significance level.

The failure to find spontaneous recovery was discussed in terms of unlearned preference for black, and the limitations of the experimental situation.

Advisor: James H. Renierse