Physiological Harmony or Discord? Unveiling the Correspondence Between Subjective Arousal, Valence and Physiological Responses

Abstract

Affective experiences are inevitably accompanied by physiological changes, however it is still a matter of intense debate whether events evoking similar affective experiences produce comparable physiological responses (fingerprint hypothesis) or variation is the norm within individuals (population hypothesis). We reanalyzed data from two independent samples (N = 491; N = 64), using representational similarity analysis (RSA) to examine the trial-by-trial similarity patterns of subjective experience of valence and arousal and affect-related physiological measures (skin conductance [SCR] and startle blink responses). Across different affect-inducing (passive picture viewing, passive sound listening, imagery tasks) tasks and samples (Ns=491, 64), we observed strong-to-decisive evidence for a correspondence between SCR and startle responses and models of arousal and valence that assume variation, especially between trials generally evoking higher responses. Our results show that similar affective experiences are rather reflected by distinct physiological responses and emphasize the importance of considering intraindividual variability in future studies to better understand how physiological changes contribute to conscious affective experiences in humans.