Psychophysiological correlates of disgust and disgust sensitivity
The main goal of this study was to estimate the correlation between various psychophysiological variables and self-reported disgust during a picture perception paradigm. We further studied disgust sensitivity (DS) as a possible moderator variable for this relationship. Forty-seven subjects (23 females) were presented with a total of 36 pictures with different disgust intensities. Each picture was shown for 8s during which different physiological parameters were registered: heart rate (HR), skin conductance response (SCR), and electromyographic activity (EMG) of the musculus levator labii. Affective ratings and viewing times were assessed after the physiological registrations. The data were analyzed using hierarchical linear models. The degree of the disgust experience reported by the subjects showed a significantly negative correlation with HR and a significantly positive correlation with SCR. Disgust-inducing pictures resulted in higher EMG responses in comparison to neutral pictures, but there was no significant correlation between self-reported disgust and EMG activity on an individual level. Elevated DS, measured by the questionnaire by Haidt, McCauley, and Rozin, (1994), led to more intense subjective responses toward disgust-inducing pictures, but this was not true for the behavioral and physiological responses.