Date of Award


Degree Type


Degree Name

Master of Arts in Psychology



First Advisor

Nelson F. Smith


The purpose of this experiment was to determine whether response prevention leads to fear reduction as assessed by approach measures, and to examine the role of safety testing behavior following response prevention. The subjects were 120 experimentally naive male rats of the Sprague-Dawley strain. The apparatus consisted of a one-way platform avoidance chamber. The procedure included avoidance training, response blocking, and fear testing phases. The experiment represented a three by four factorial design. Eighty avoidance trained subjects were assigned to blocked or non-blocked conditions. The remaining control subjects were never shocked. Ten subjects from each of these treatment conditions were assigned to either a very low, low, medium, or high platform level. The results confirm ed the hypothesis that response prevention does lead to a partial but in complete reduction in fear. The results revealed that blocked subjects approached the grid sooner, spent more time on the grid before returning to the platform, spent more time on the grids during the five hour fear test, safety tested less frequently before approaching the grid, and safety tested sooner than non-blocked subjects. Although the blocked and control groups did not differ in total time on grid, number of approaches, first time spent on grid, and number of safety tests before first approach, the blocked group had significantly longer approach and safety test latencies than the control group. Platform height did not have a significant effect on approach latencies. Either fear elimination or fear reduction was found, depending which dependent measure was used to assess fear. The safety test data showed that safety testing behavior is clearly indicative of fear. The differential role of safety testing behavior for blocked and non-blocked subjects was discussed. Implications of the results to clinical practice and research were presented.



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