The relevance of experimental studies to clinical applications of biofeedback.

In support of the proposition that a lack of basic research on the processes of biofeedback restricts the development of effective practical applications, this paper deals with some of the basic interconnections between theoretical issues and clinical practice and presents illustrations of a few issues that have actually been investigated. Regarding the issue of the nature and form of the feedback, studies have shown that reinforcing feedback appears to be more effective than merely informative feedback, and that the choice from among digital, binary, or analog feedback arrangements should be based upon functional properties of the neural control system that underlies the physiological process to be modified. For example, analog feedback may not be optimal if the underlying control system actually functions digitally. Regarding the issue of specific versus diffuse effects of biofeedback, the evidence reviewed suggests that biofeedback's direct effects tend to be more specific than generalized. Those generalized changes that have been obtained are probably indirect or secondary, rather than direct. The paper concludes that the balance of basic and applied work in biofeedback must be shifted toward the more fundamental in order to provide a better basis for practical application. Otherwise, the promise of biofeedback will continue to exceed its actual success.