Dynamic versus static indicators of threat: N2 and LPC modulation index attack intent and biological relevance during an affective Flanker task.

Biological relevance may influence the neural response towards images which depict attack intent. In the present study, images featuring reptiles and firearms were employed as target and flanking stimuli in a modified version of the affective Flanker task. Forty-two participants (21 male) completed the modified Flanker task as EEG was recorded. Congruency effects in reaction times were more consistently observed for arrays with firearm targets than for arrays with reptile targets. Arrays with neutral targets (i.e., water pistols, turtles) evoked more negative mean N2 (250–400 ms) amplitudes than those with attack targets (i.e., attacking snakes, aimed handguns), while arrays with aimed handgun targets elicited more positive mean activity for the late positive component (LPC; 450-650 ms) compared to arrays with water pistol or reptile targets. Congruency effects were also found in N2 activity for arrays with firearm targets and reptile Flankers. In addition, LPC amplitude for incongruent arrays with attack targets and neutral Flankers was reduced compared to congruent attack arrays. These findings suggest that biological relevance influences interference processing (the N2) and intersects with attack intent during the later stages of picture processing (the LPC). • Flanker paradigm used to investigate processing of static and dynamic threat cues • Influence of biological relevance on interference processing indexed by N2 activity • Biological relevance and attack intent interacted in LPC modulation. • Aimed handgun targets evoked more positive LPC than attacking snake targets. • Suggests dynamic and static threat cues differentiated during picture processing [ABSTRACT FROM AUTHOR]