91��ү

G’day Web Surfer,

I am a professor of Psychology in the Psychology Department at 91��ү.  My area of expertise is learning.  Broadly defined, learning refers to a change in behavior as a function of experience.  Theories of learning refer to the ways in which experience affects behavior.  Two major learning processes are classical and operant conditioning. In classical conditioning, our nervous system discerns neutral sensory events that predict biologically relevant events.  Due to this predictive association, our nervous system begins to respond in the presence of these neutral sensory events in preparation for the associated biologically relevant event.  Our behavior changes so that we now respond in the presence of the neutral sensory event.  In operant conditioning, the consequences that arise from our behavior in a particular context change our behavior.  If we come to be less likely to do that behavior in that context in the future, then the effect of the consequence was punishment.  If, on the other hand, we are more likely to do that behavior in that context in the future, then the effect of the consequence was reinforcement.  The Law of Effect, as formulated by Thorndike, is that we look to the effect of a consequence on behavior to define it as reinforcement or punishment – and nothing else.

My background is in this latter process.  I had the privilege to study under very accomplished mentors during my graduate training.  First, I was fortunate to work with Dr. W. David Pierce, a behavior analyst, in the Department of Sociology at the University of Alberta.  Dr. Pierce is best known for an animal model and biobehavioral theory of activity anorexia.  Activity anorexia occurs when animals experience a reduction in food intake that leads to a loss of body weight; subsequently, the loss in body weight enhances physical activity, which further decreases appetite and food intake, depletes body reserves and drives physical activity upward. The culmination of this feedback cycle is starvation and death of the animal.

My research under Dr. Pierce’s supervision involved a comparison of choice behavior by humans and pigeons.  To assess choice behavior in humans, a human operant conditioning chamber was constructed in the Centre for Experimental Sociology in the Henry Tory Marshall building.  The choice behavior of pigeons was assessed in standard operant conditioning chambers in the Department of Psychology in the Biological Sciences building.  Training and testing conditions for humans and pigeons were as similar as possible.  Dr. Edmund Fantino’s delay reduction theory of conditioned reinforcement was assessed using concurrent-chain schedules of reinforcement.  Results showed that the choice behavior of pigeons was consistent with the prediction of delay reduction theory that response allocation would reflect the relative strength of stimulus lights in the concurrent chains as conditioned reinforcers.  In contrast, human choice behavior was systematic, but did not conform to delay reduction theory.  Instead, the performance of the human participants was assumed to reflect maximization.

Although setting up and completing the experiment was a daunting task, the novelty of this approach to directly comparing the responding of humans and non-humans was instrumental in my acceptance to the graduate program in Psychology at Harvard University and the opportunity to train under the supervision of Dr. Richard Herrnstein and Dr. Gene Heyman.  Dr. Richard Herrnstein is best known within the field of the experimental analysis of behavior for having formulated the “matching law”.   This law of choice describes how allocation of choices between alternatives matches the relative rate of payoffs from those alternatives.  Dr. Gene Heyman is best known for developing a theory of addiction as a disorder of choice.  My time at Harvard under the supervision of these mentors was the period of greatest intellectual development in my academic career.

In the Pigeon Lab, I was given opportunity to work closely with a group of highly motivated graduate students and use the available resources to conduct numerous experiments guided by the intellectual expertise of Dr. Richard Herrnstein, Dr. Gene Heyman, and Dr. Will Vaughan.  My Ph. D. Dissertation was a collection of three experiments investigating the reinforcing properties of wheel running in rats using the hyperbolic matching law equation formulated by Dr. Richard Herrnstein.  This was the origin of the research program that I continue to pursue to this day in conjunction with the hard working, highly motivated, intellectually capable Psychology undergraduate students at 91��ү.   It has been, and continues to be, a pleasure to work with and guide the intellectual development of these students as did my mentors for me.