The current status of the concepts of physiological response specificity and activation

The history of concepts of activation and specificity in psychosomatic medicine is briefly reviewed. The limitations of current definitions of activation are discussed and a broader definition which incorporates response specificity, including both stimulus response specificity and individual response specificity, is suggested. The implications of this broader definition for the design and interpretation of experiments are discussed using illustrations drawn from recent research in psychosomatic medicine and psychophysiology.