ارزیابی شایسته سازی: یک توضیح احتمالی برای دستیابی به واکنش های نفرت انگیز؟

The present study attempted to demonstrate that through the contingent presentation of subjectively neutral pictures (CS) with disgusting pictures (US), the neutral stimuli will acquire the ability to evoke psychophysiological disgust responses. It was also investigated if this effect is more pronounced in individuals who are characterized by an elevated disgust sensitivity or blood-injury fear. Forty females underwent a learning experiment following the evaluative conditioning paradigm. The subjects were presented with 18 pictures depicting disgusting (D), pleasant (P), and neutral (N) scenes, displayed in pairs of 3 N-D, 3 N-P, and 3 N-N. Each pair was repeated 6 times. During the picture presentations, the facial EMG of the M. levator labii, the heart rate, the skin conductance, and blood pressure were recorded. Affective ratings for the pictures were determined before and after the experiment. The viewing of the disgusting US pictures led to increases in muscle tension, skin conductance, and heart period, but had no effect on blood pressure. Subjects with a high degree in disgust sensitivity and blood-related fears showed more pronounced EMG responses to the US disgust pictures and rated them as more disgusting than the low-scorers. There was no indication of disgust conditioning within the whole sample neither for the subjective nor for the physiological measures. However, the blood-fearful group showed a stronger increase in EMG activity toward the neutral pictures that had been paired with the disgusting ones compared to low-fearful subjects. This could be interpreted as evaluative conditioning.