Autonomic Specificity and Emotion

Abstract

Autonomic specificity refers to the notion that emotions can be distinguished in terms of their associated patterns of autonomic nervous system activity. This idea has a long history in psychology, tracing back at least to James’s (1884) writings on the nature of emotion. Moreover, it is an idea that has always been shrouded in controversy, attracting many critics along the way (e.g., Cacioppo, Klein, Berntson, & Hatfield, 1993; Cannon, 1927; Schachter & Singer, 1962; Zajonc & McIntosh, 1992). The controversy has been framed by two immoderate assertions: (1) Every emotion is autonomically unique; and (2) every emotion is autonomically the same. The uniqueness assertion is generally associated with Alexander’s (1950) psychosomatic hypotheses. The second assertion of sameness arguably finds its clearest statement in Mandler’s (1975) writings. Needless to say, these are both statements in extremis, and it would be difficult to find undiluted, unhedged versions of either in the contemporary literature. Nonetheless, they form the two poles around which participants in the debate over autonomic specificity have aggregated over the decades. In my view, both of these assertions are highly dubious. Regarding the first assertion of uniqueness, as I hope this chapter makes clear, it is highly likely that reliable autonomic differences only exist for a small number of emotions. Moreover, where these differences do exist, they are likely to be “prototypical” in nature, with particular occurrences of a given emotion showing variation around these central tendencies. Similarly, there is ample basis for rejecting the second assertion of no autonomic differences among emotions. An examination of the empirical literature reveals many studies that report evidence of autonomic specificity. A flurry of such studies appeared after Ax (1953) developed a paradigm for using “real life” inductions to study this issue in the laboratory. Another flurry appeared 30 years later following our report (Ekman, Levenson, & Friesen, 1983) that used directed facial actions and relived emotional memories to address the same question. In contrast, there are surprisingly few published empirical studies that report failures to find any evidence for autonomic specificity. Most of the support for the “sameness” position comes from a number of influential critiques that have either discounted autonomic specificity on a priori grounds (e.g., Cannon’s argument that the autonomic nervous system was structurally incapable of supporting specificity; Cannon, 1927) or that have criticized existing data (e.g., Zajonc & McIntosh, 1992) without presenting any new data. The other source of “support” for the sameness position has derived from studies that have followed the paradigm introduced by Schachter and Singer (1962) in which the autonomic nervous system is activated by using some nonemotional agent (e.g., injection of epinephrine). Participants’ emotional labeling of the resultant state is shown to be quite malleable, reflecting cues in the experimental environment.