, Nevin J. IBN-9507584 "Resistance to Change, Preference, and the Law of Effect" One of the oldest principles of psychology is the Law of Effect, which states that rewards strengthen the behavior that produces them. However, the relation between the value of a reward and its effectiveness in strengthening behavior remains unclear. Over the past 20 years, PI has interpreted the strength of behavior as the resistance of well-learned behavior to change, and has shown that resistance to change depends directly on the frequency or amount of reward signaled by a distinctive stimulus situation. At the same time, methods for measuring reward value, interpreted as preference between stimulus situations that signal various frequencies or amounts of reward, have become progressively more precise. Both lines of research have led to findings that are quite general across species and situations; however, no research has attempted to measure preference and resistance to change at the same time, in an individual subject, which is necessary to determine how these measures are related to each other. The proposed experiments will study preference and resistance to change in pigeons working for food rewards under a variety of conditions designed to isolate a mathematical expression relating them. That relation will be a quantitative statement of the Law of Effect.
