Abstract:

As one kind of threat related emotions, disgust has the evolutional meaning to help human being avoid harmful stimulus. Recent studies have demonstrated the unique neural processing mechanism of disgust, which could be described as inhibiting sensory inputs at early stage of stimulus processing. In this study, the event-related potential (ERP) technique was employed with its advantage in time resolution to learn about the neural processing when participants watching disgusting compared with neutral pictures. After watching emotional pictures presented in different lengths of time, participants were instructed to finish a visually search task in order to examine the consumptions of attentional resources under different conditions. EPR results revealed that the effect of disgust first began at 100 ms after picture onset with a suppressed waveform compared to the neutral condition while enhanced neural activity was detected at the follow-up stage of detailed processing. The behavior results showed significant interactions; the task performance was hampered by negative emotion processing when the stimulus length was shorter (0/300 ms). In contrast, there was no behavioral difference between two emotional conditions when the stimulus length was longer (600/900 ms). The current results suggest that disgust has unique neural processing mechanism which fits the tow-stage model of negative emotion processing. The results further indicate that there is transition phase existing in which both automatic processing and controlled processing activate simultaneously.

Key words: disgust, automatic processing, top-down processing, attention