Effect of positive emotions on perceptual processing of visual probes

The late positive potential (LPP) is an event-related potential that increases in response to emotional stimuli. Brown et al. investigated the functional significance of LPP. They induced the LPP by presenting unpleasant pictures and reported that N1 in response to a visual probe, which reflects perceptual processing in the visual cortex, was attenuated compared to N1 when neutral pictures induced the LPP. This finding suggested that visual cortex activity is inhibited during LPP elicitation (global inhibition hypothesis). However, they did not examine the activity of the visual cortex during LPP induced by pleasant pictures. Based on previous research reporting that positive emotions enhance motivation and cognitive activity (e.g. broaden and build theory), we hypothesize that perceptual processing of visual probes during LPP is enhanced by pleasant pictures, which increase N1 to the visual probe.

We investigated this hypothesis by presenting visual probes during LPP generated by emotional pictures following Brown et al.

The results demonstrated that the N1 amplitude increased, and response times to visual probes decreased during the LPP induced by pleasant pictures compared to unpleasant pictures.

These findings suggest that positive emotions elicited by pleasant pictures enhanced the perceptual processing of visual probes, which is suggestive of the approach function of LPP during positive emotional experiences.