Functional significance of the emotion-related late positive potential

Abstract

The late positive potential (LPP) is an event-related potential (ERP) component over visual cortical areas that is modulated by the emotional intensity of a stimulus. However, the functional significance of this neural modulation remains elusive. We conducted two experiments in which we studied the relation between LPP amplitude, subsequent perceptual sensitivity to a non-emotional stimulus (Experiment 1) and visual cortical excitability, as reflected by P1/N1 components evoked by this stimulus (Experiment 2). During the LPP modulation elicited by unpleasant stimuli, perceptual sensitivity was not affected. In contrast, we found some evidence for a decreased N1 amplitude during the LPP modulation, a decreased P1 amplitude on trials with a relatively large LPP, and consistent negative (but non-significant) across-subject correlations between the magnitudes of the LPP modulation and corresponding changes in d-prime or P1/N1 amplitude. The results provide preliminary evidence that the LPP reflects a global inhibition of activity in visual cortex, resulting in the selective survival of activity associated with the processing of the emotional stimulus.

Neural modulation of directed forgetting by valence and arousal: An event-related potential study

“…Electrical brain activity associated with words and cues presented during encoding were separately analyzed. During word processing, the LPC was the component of interest as our primary focus was in the intentional processing of these words (Brown et al, 2012;Citron, 2012). Consistent with the literature, a greater LPC over centro-parietal and parietal electrodes was expected to emerge for words high in valence, despite arousal levels (e.g., Bayer et al, 2010;Olofsson et al, 2008;Recio et al, 2014).…”

“…According to the literature, the LPC is argued to reflect selective attention toward and processing of emotional stimuli (Brown et al, 2012). Moreover, the neural substrate of the LPC is thought to consist of a network of cortical and subcortical structures, such as the visual cortices, prefrontal cortex, parietal cortex, and deep emotion-processing structures (e.g., insula, amygdala; Liu, Huang, McGinnis-Deweese, Keil, & Ding, 2012).…”

“…This early deflection is thought to reflect initial attentional orientation to emotional stimuli that is independent of task demands (e.g., Citron et al, 2013;Recio et al, 2014). Following this early component, the LPC peaks around 400-600 ms following stimulus onset but has also been shown to persist for up to one second following stimulus offset (Brown, Steenbergen, Band, de Rover, & Nieuwenhuis, 2012). The LPC is modulated by both valence and arousal with more positive activity emerging for stimuli that are highly arousing versus low arousing and also for items high in positive or negative valence relative to neutral stimuli.…”

Effects of age and task difficulty on ERP responses to novel sounds presented during a speech-perception-in-noise test

“…Interestingly, participants with a hearing loss tended to have larger LPP but not Novelty P3 amplitudes, compared to the normal-hearing participants. Based on the similarity of the LPP in our study with visual and auditory LPPs from other areas of research, such as emotional facial expressions (e.g., Brown et al, 2012;Hajcak et al, 2010) and music perception Istok et al, 2013;Müller et al, 2010), we interpreted the LPP as a component modulated by the emotional rather than cognitive aspects of the task, possibly reflecting the arousal level and thus, the listening effort of the person. While both Novelty P3 and LPP were affected by changes in task difficulty, LPP appeared to be the more sensitive component for capturing listening effort.…”

Motivational significance and cognitive effort elicit different late positive potentials

“…This hypothesis assumes that slow negative shifts are a sign of higher excitability, whereas slow positive shifts are a sign of reduced excitability or inhibition of cortical cell assemblies (Rösler et al, 1997). On the basis of this hypothesis, Brown et al (2012) argued that the LPP elicited by affective content reflects a global inhibition of activity in the visual cortex, which may allow for more selective processing of the affective stimulus by impairing the perception of subsequent insignificant stimuli. Rösler et al (1997) also argued that a negative or positive slow wave in a cognitive task reflects the activation or inactivation, respectively, of the cortex nearby, and that the amplitude of a negative slow wave could be related to more resource allocation for the task.…”