N270 sensitivity to conflict strength and working memory: A combined ERP and sLORETA study

Abstract

The event-related potential N270 component is known to be an electrophysiological marker of the supramodal conflict processing. However little is know about the factors that may modulate its amplitude. In particular, among all studies that have investigated the N270, little or no control of the conflict strength and of the load in working memory have been done leaving a lack in the understanding of this component. We designed a spatial audiovisual conflict task with simultaneous target and cross-modal distractor to evaluate the N270 sensitivity to the conflict strength (i.e., visual target with auditory distractor or auditory target with visual distractor) and the load in working memory (goal task maintenance with frequent change in the target modality). In a first session, participants had to focus on one modality for the target position to be considered (left-hand or right-hand) while the distractor could be at the same side (compatible) or at opposite side (incompatible). In a second session, we used the same set of stimuli as in the first session with an additional distinct auditory signal that clued the participants to frequently switch between the auditory and the visual targets. We found that (1) reaction times and N270 amplitudes for conflicting situations were larger within the auditory target condition compared to the visual one, (2) the increase in target maintenance effort led to equivalent increase of both reaction times and N270 amplitudes within all conditions and (3) the right dorsolateral prefrontal cortex current density was higher for both conflicting and active maintenance of the target situations. These results provide new evidence that the N270 component is an electrophysiological marker of the supramodal conflict processing that is sensitive to the conflict strength and that conflict processing and active maintenance of the task goal are two functions of a common executive attention system.

Electrophysiological Correlates of Change Detection during Delayed Matching Task: A Comparison of Different References

“…Besides, only the REST-obtained N270 showed a significant increment in the task-irrelevant feature change. This finding was compatible with the delayed behavioral performance, and therefore is consistent with the view that frontal conflict control mechanism characterized by N270 is responsible for regulating external behavioral conflicts (Zhang et al, 2008 ; Yin et al, 2012 ; Scannella et al, 2016 ). Obviously, the interpretation of the ERP results varied with the references used, and only the REST provided the closest approximation to the relevant literatures and the delayed behavior performance.…”

“…Cortical source localization evidences showed that N270 may generate from the anterior cingulate cortex (ACC) (Yin et al, 2012 ). In consideration of a strong connectivity existing between ACC and the dorsolateral prefrontal cortex (DLPFC) (Wang et al, 2010 ), it was proposed that N270 reflects the downstream process (Zhang et al, 2008 ; Scannella et al, 2016 ). This mechanism is based upon the afferent ACC signals and takes place within the DLPFC to generate an appropriate behavior response (Scannella et al, 2016 ).…”

“…However, no corresponding electrophysiological signal was found from this brain area. What needs to be pointed out is that previous studies focused on this process mainly used the linked mastoid (LM) as the reference (Cui et al, 2000 ; Wang et al, 2002 ; Li et al, 2003 ; Sun et al, 2008 ; Scannella et al, 2016 ), which is the average of the left and right mastoids. While Yao et al ( 2005 ) found that LM-obtained EEG power was markedly shifted to the frontal and superficial positions in an unreasonable way.…”

A Facilitatory Effect of Perceptual Incongruity on Target-Source Matching in Pictorial Metaphors of Chinese Advertising: EEG Evidence

“…The most important processing that moderates the cognitive outcome in these studies is matching comparison, operationalized by the degree to which the compared dimensions are incongruous to each other. The electrophysiological findings typically relating to the incongruity of the processing of visual metaphor are those by Scannella et al (2016), who claimed that N270 is sensitive to the conflict strength. In the context of advertising, Szubielska et al (2012) found that the amplitudes of information conflicting components (N270, P300, and N400) were sensitive to incongruity between the product category and the previously presented brand.…”

The N270 in Facial S1-S2 Paradigm as a Biomarker for Children With Attention-Deficit/Hyperactivity Disorder

“…In previous studies, when presenting a mismatch stimulus to the preceded stimulus to participants, a negative ERP component potential with peak latency of approximately 270ms (N270) was recorded [23], [24]. N270 was explored by S1-S2 paradigm and evoked by the mismatch between the presentation in working memory and the following perceptual input [25]. Cognitive basis of N270 is processing of working memory representation conflict [25].…”