The Influence Of The Valence Of Negative Emotion On Cognitive Process

Though the humans are more susceptible to unpleasant stimuli of higher intensity, how the valence intensity of unpleasant stimuli impacts subsequent cognitive processing, and whether this impact increases with the unpleasantness, require clarification. For this purpose, event-related potentials (ERPs)were recorded for highly negative (HN),mildly negative (MN) and neutral cueing pictures, and subsequently for the non-emotional target picture while subjects were required to discriminate the location of the target. Cue-induced ERPs showed more negative deflections for the HN than for the neutral pictures in the450-650ms time interval. The emotion effect for the MN cueing stimuli, however, was non-significant in this interval. In contrast, target-induced P3amplitudes were significantly more negative following MN versus neutral cueing pictures, while the P3amplitudes were not significantly different between HN and neutral conditions, irrespective of cueing validity. Thus, despite weak immediate impact, MN stimuli influenced subsequent target processing more heavily than HN stimuli. This suggests that the impact of unpleasant events on cognition doesn’t necessarily increase with the unpleasantness. Mild unpleasant stimulus, which is weak in immediate emotion arousal, should not be neglected due to the likelihood of producing a sustained impact.To investigate the distinct sensitivity to fearful face between the low-aggressive and high-aggressive individuals with Event-related potentials (ERPs). The present study adopted neutral and fearful expression face as materials (from CAPS), filtered the subjects to the high-aggressive and low-aggressive groups according to the scores of The Aggression Questionnaire. The ERP results showed that:the P1amplitudes indicated that fearful condition elicited bigger amplitudes than neutral condition. And the N170amplitudes showed the trend that angry expression evoked more negative components than fearful expression, which demonstrated that the emotion salience significantly impacted early visual processing. The most important results was that the frontal area exhibited interaction between aggressivity and emotion in250-300ms:in the low-aggressive group, fearful expression elicited more negative components than neutral expression, whereas in the high-aggressive group, there was no significant difference between the two expressions.The result contributed the previous research that reduced ventromedial prefrontal response to angry facial expression in subjects scoring high on reward-drive (more likely to display aggressive behaviour) that:besides angry expression, high aggressive individuals tend to inactivated neural response to fearful expression as well. Therefore, we can form a hypothesis that high aggressive individuals are insensitive to threatening-related facial expressions. Additionally, this research strengthened the evidence that the high-aggressive individuals lack the ability of inhibitory control in the prefrontal brain regions. The electrophysiological evidence of the present study shows high aggressive individuals lack the early frontal response to fearful face. Combined with previous neuroimaging and ERP studies, we can draw a hypothesis that heightened aggression is associated with inactivated neural response to threatening facial expressions in ventromedial prefrontal cortex.