The impact of extraversion on attentional bias to pleasant stimuli: neuroticism matters

The present study explored whether neuroticism modulates the impact of extraversion on attention orienting to pleasant and unpleasant pictures of diverse emotional intensities. We measured event-related potentials for highly emotional, mildly emotional, and neutral stimuli in both pleasant and unpleasant blocks, while subjects (16 stable ambiverts, 15 stable extraverts, 17 neurotic ambiverts, and 17 neurotic extraverts) were asked to perform a standard/deviant categorization task, irrespective of the emotionality of the deviants. The results revealed a modulation effect of neuroticism in the impact of extraversion on emotional attention. On the one hand, irrespective of extraversion, emotionally stable samples showed increased N200 amplitudes for highly unpleasant (HN) stimuli relative to mildly unpleasant (MN) and neutral stimuli, while these samples exhibited no significant emotion magnitude effect in the pleasant block. On the other hand, although neurotic samples, both extraverts and ambiverts, showed enhanced N2 amplitudes for HN stimuli than neutral stimuli, neurotic extraverts displayed increased N2 amplitudes for highly pleasant (HP) and mildly pleasant (MP) stimuli than neutral stimuli, which was absent in neurotic ambiverts. These results extend our understanding of the relationship between extraversion and emotion by showing that neuroticism amplifies the positive emotional bias of extraverts.