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Two experiments were conducted to determine the conditions under which a shift problem vs, a stay problem would be easier for animals tested on Maier's three-table task. When animals were given a prior exploratory experience and a partial feeding during the feeding experience, the stay problem was easier. With a prior exploratory experience and a complete feeding experience, the shift solution was easier. In the absence of prior exploration, rats cannot solve either the stay or shift problem, regardless of the amount of feeding during the feeding experience.

Three experiments were performed to explore the relationship between leverpress escape behavior and pituitary-adrenal activity. In Experiment 1, concentrations of plasma corticosterone increased from basal levels during exposure to the shock escape procedure, but were substantially decreased following the 15th escape conditioning session. In Experiment 2, steroid levels of subjects which received inescapable shock remained elevated during exposure to all 15 shock sessions. Experiment 3 examined whether normal pituitary-adrenal arousal was necessary for learning and maintenance of successfulleverpress escape behavior. Subjects for which hypothalamic cortisol implants blocked pituitary-adrenal activity learned the escape response and performed efficiently, although their escape latencies showed a small, but significant, increase over latencies of cholesterol-implanted control subjects. Collectively, these results suggest that pituitary-adrenal activity may reflect rather than mediate the acquisition of coping behavior.

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