by Keith Sonnanburg, Ph.D.
When I teach introductory psychology, I often prompt people to imagine a visit to their favorite restaurant. They muse about the sights, the smells and their anticipation of a good meal. I ask if anybody notices a change in their own bodily states. Many report that they salivate. Others report that they do not. I ask the people who did not salivate to raise their hands. These simple requests demonstrate the special focus of psychology. By making noises at a podium, I change body chemistry. In response to my words, there are pervasive changes in cerebral activity, in autonomic nervous system functioning, in muscle contractions. The microphysiological effects of psychological interventions are so profound that we need no complicated equipment to detect the outcomes.
Using current technology, we can watch blood flow in the brain as a person solves mathematical problems or prays. We can unequivocally demonstrate that lasting changes in brain chemistry result from psychotherapy alone. We can measure stable physical changes in neurons recruited for learning new responses. We learn that the medical health of the body is profoundly affected by psychological variables, and understand how that comes to be. In sum, it is psychology that explains these changes in biochemistry and physiology.
Neurophysiology can affect psychology, by limiting the range of possible responses. But psychological phenomena are still linked to their role in the environment (even when the link is distorted by dysfunction or damage to the biological resources that allow them). When neurons are irretrievably damaged, psychologists train compensatory skills. When pharmacology corrects biochemical anomalies, people still must meet personal and social challenges. When biological processes are destabilized by behaviors and emotions, habits and lifestyles become the targets for change. Psychology is not supplanted by other disciplines, nor can its subject matter be adequately addressed through reliance on them. The science of psychology uniquely focuses on the adaptive fit between the responses of individuals and their environments.