Contribution of N170 Component in Subjective Time Distortions of Facial Emotions

1. Facial Expression 2. Time Perception 3. Arousal Introduction: Emotional effects on human time perception are generally attributed to the arousal factor, which is hypothesized to be responsible for speeding up or slowing down the internal clock. The aim of the present study was to investigate the arousal effect on time distortion with the help of event-related potentials (ERPs) that can provide direct electrophysiological measures of arousal rather than self-report indices which have been the common approach in the previous studies. In this study, a temporal bisection task was employed to assess the temporal responses of participants to emotional faces that varied in arousal dimension. The N170 component was used as an objective measure of induced arousal by different emotional faces. Materials and Methods: Electroencephalography was recorded in 20 participants who performed a temporal bisection task using high arousal pleasant stimuli (happy faces) and neutral ones as stimuli. Results: Behavioral data revealed that temporal bisection points were significantly smaller for high arousal pleasant stimuli (happy faces) compared to neutral ones, while changes in N170 amplitude were independent of the emotional modulation of facial stimuli. Conclusion: In the light of the dual-stage theory of emotional processing, it seems that the N170 component is not appropriate to measure the arousal index of emotional faces .in implicit tasks, and probably later components may be a better indicator for this index.x ABSTRACT Article Info: