Date of Award


Degree Name

Master of Arts



First Advisor

Dr. Roger E. Ulrich

Second Advisor

Dr. Doug Anger

Third Advisor

Dr. Frank Fatzinger

Access Setting

Masters Thesis-Open Access


In Experiment I, the effects of low fixed ratios on individual escape behavior of rats was studied. When FR sessions were compared to CRF sessions, measures related to shock delivery showed highest percentage increases, especially at FR-5.

Animals were then paired. Two schedules were analyzed as alternatives to individual escape. In Experiment II, shock was terminated when a specified FR was completed, either by the responses of one animal or by the total responses of both animals. Escape as a function of both animals responding was not maintained. In Experiment III, shock was terminated individually as before, or when both animals emitted a single response. Under these conditions, "cooperative" escape was maintained.

When animals were allowed access to one another as well as to their respective response levers, little fighting occurred regardless of the schedule programmed. When escape contingencies were removed, a high rate of fighting occurred with one pair.