Affective response to color-slide stimuli in subjects with physical anhedonia: a three-systems analysis.

Emotion-provoking visual stimuli were presented to college undergraduates identified as anhedonic or normal, based on their scores on the Physical Anhedonia Scale (Chapman, Chapman, & Raulin, 1976). The affective stimuli (35 mm color slides) were chosen to elicit a wide range of both positive and negative emotion, with emotional response assessed through affective judgments, viewing time, and monitoring of a variety of physiological systems (heart rate, skin conductance, and facial musculature). The experiment was successful in demonstrating differential emotional response in the two subject groups; anhedonic subjects reported a less positive response than control subjects to positive and neutral stimuli and showed no association between heart rate and the emotion content of the slides. Paradoxically, activity in the muscles of facial expression was greater in anhedonic than control subjects during the presentation of both positive and negative slides. No between-group differences were noted in the viewing-time measure. The results are discussed in the context of Lang's bioinformational theory of human emotion (Lang, 1984, 1985).