Effects of valence and arousal on affective priming vary with the degree of affective experience denoted by words

We investigated whether the effect of the valence and arousal of less or more affective experiential words on affective priming using event-related potentials (ERPs). The stimuli included less affective experiential (LE) words (Experiment 1) and more affective experiential (ME) words (Experiment 2) that were organized in an orthogonal design, with valence (positive and negative) and arousal (low and high) as factors in a lexical decision task. In Experiment 1, the results revealed no obvious effect of affective priming on response times (RTs) or ERPs for LE words. In Experiment 2, affective priming effects of ME words were influenced interactively by valence and arousal. Specifically, for positive ME words with high- and low-arousal, affectively incongruent trials were associated with longer RTs and enhanced late positive components (LPCs, 430-700 ms) compared with congruent trials (a positive effect). For negative ME words with low-arousal, no significant differences in RTs or LPC amplitudes were found between affectively congruent and incongruent trials (a null effect), whereas for negative ME words with high-arousal, the processing of congruent trials was associated with longer RTs and enhanced LPC amplitudes over that of incongruent trials (a reversal effect). On the one hand, our findings suggest that LE and ME words as primes produce different effects on the processing of subsequently presented targets. On the other hand, our findings further indicate that there seems to have a continuous transition from the spreading activation of ME words to an inhibition process in semantic memory along with their valence and arousal, which is involved in decision-making processes and memory-related stages.