Cognitive conflict could facilitate negative stimulus processing: evidence from trait anxiety in the flanker paradigm

The present study used event-related potentials to investigate the affective priming effect of cognitive conflict and the influence of trait anxiety during the early stage of conflict processing. Participants with relatively high-trait or low-trait anxiety were tested using a combination of flanker task (congruent or incongruent arrows) as primes presented 200 ms before positive or negative words as targets. Behavioral results showed that response times were shorter for negative targets following incongruent primes relative to congruent primes, and vice versa, suggesting that conflicts facilitated the processing of negative targets. Event-related potential results revealed that the N2 amplitudes (280-320 ms) for incongruent stimuli were significantly more negative than those for congruent stimuli, indicating a significant conflict effect. Moreover, the N400 amplitudes (580-680 ms) for positive targets after congruent primes were significantly more negative than those after incongruent primes, but no significant difference was found in the N400 amplitudes after congruent primes and incongruent primes for negative targets, indicating that conflicts had a negative effect on the subsequent processing. In addition, in the high-trait anxiety, the N400 amplitudes for negative targets after incongruent primes were significantly more negative than those after incongruent primes, and vice versa, indicating that conflicts facilitated the processing of negative targets. These findings showed that conflicts could facilitate the processing of negative targets and be viewed as aversive signals during the early stage of conflict processing and that high-trait anxiety promoted the negative effect induced by conflicts.