Evaluative processing of emotional and moral content during discourse comprehension: Insights from event-related brain potentials

The present experiment examined whether an affective evaluation process contributes to discourse comprehension when participants silently read for comprehension, by analyzing event-related potentials (ERPs). Kunkel, Filik, Mackenzie, and Leuthold (2018) showed that when participants read about emotional events or moral transgressions while performing explicit emotional judgments, a larger late positive potential (LPP) was triggered for negative versus non-negative and immoral versus moral scenarios. They took this LPP effect to reflect the affective evaluation of incoming linguistic information with emotional content. Previous work showing implicit evaluation of morality-based materials (i.e., when participants are simply reading for comprehension) had intermixed these stimuli with emotionally-neutral world knowledge violation materials (Leuthold, Kunkel, Mackenzie, & Filik, 2015). By placing these morality materials with emotion-related materials instead, in the current study, we can more directly evaluate whether similar affective processing occurs for both types of stimuli in the absence of an explicit judgment task. Target sentences from negative versus non-negative emotional scenarios and from moral versus immoral scenarios were presented using rapid serial visual presentation. Importantly, the analysis of single-trial amplitudes using a linear mixed-effects modeling (LME) approach revealed a larger late positive potential (LPP) for negative versus non-negative and immoral versus moral scenarios, displaying a more posterior distribution for emotion versus morality condition effects. We conclude that discourse comprehension involves the implicit affective evaluation (LPP) of the emotional content of incoming linguistic information independent of the material-specific context.