Analysis of Biological Response to Pleasure Elicited by Video

To study the objective evaluation of emotions, and pleasure in particular, biological responses to emotional videos were investigated. Fifteen adult males participated in the experiment. Five videos were used, which engendered “exhilaration,” “happiness,” “being comforted,” “disgust,” and “control.” Impedance plethysmography, electrocardiogram, photo plethysmography, continuous blood pressure, and respiration were measured and analyzed. Self-rated scores for “pleasure–displeasure” adequately varied among emotional-video stimuli. Biological changes were observed in the “exhilaration” condition, such as heart rate (HR), pulse wave amplitude, and pulse pressure. However, no biological changes in common were found among pleasurable emotions. To determine biological responses common to pleasurable emotions, the pulse wave was assessed in detail. Consequently, arterial compliance tended to decrease for each pleasurable emotion, albeit non-significantly. The maximum of the differentiated pulse wave (dP) changed significantly for “exhilaration” and “happiness.” Moreover, the combined parameter, which involved dP, HR, and mean blood pressure changed significantly for all pleasurable emotions.