ABSTRACT
Explanatory concepts enable scientists to categorize and understand large amounts of data. They also suggest hypotheses to be tested and questions to be asked by investigators of various phenomena and, thus, help to guide the researcher. The answers obtained through experimental study may suggest modification or elaboration of existing concepts, or a relationship with other formulations. Within the field of psychophysiology, the most elaborate of the concepts deal with cardiovascular or autonomic activity in one form or another. Concepts concerning brain responses are as numerous, but not as well developed. In addition, there are formulations regarding electrodermal activity (EDA) and muscle activity. Thus, the field of psychophysiology does not have an all-inclusive conceptual framework within which most of the collected data may be tested, integrated, and interpreted. Instead, there are a number of concepts that have relevance for the interpretation of experimental findings. Some of these concepts, at least in part, contradict one another. Perhaps one day the various concepts may be reconciled and subsumed within one or a few theoretical frameworks that will account for most of the existing data. This is probably an overly optimistic goal, but one for which scientists in diverse areas, including psychophysiology, constantly strive.
