An extinction-induced increase in an aggressive response with humans¹

¹Experiment I is based on a thesis submitted by the first author in partial fulfillment of the M.A. degree at Southern Illinois University. The investigation was supported by grants from the Mental Health Fund of the Illinois Department of Mental Health and Grants MH-14280 and MH-04926 from the National Institute of Mental Health. Dr. R. Campbell and Dr. E. Sulzer provided valuable advice during the planning of the study and in the preparation of the manuscript. The authors also appreciate the valuable suggestions of Drs. N. H. Azrin, R. R. Hutchinson, H. B. Rubin, and Mr. Jay Powell. Reprints may be obtained from D. F. Hake, Behavior Research Laboratory, Anna State Hospital, Anna, Illinois 62906.