A late locus of the distractor frequency effect in picture-word interference: evidence from event-related potentials

In this study, we investigated how people deal with irrelevant contextual information during speech production. Two main models have been proposed. WEAVER++ assumes that irrelevant information is removed from the production system by an early blocking mechanism. On the other hand, the response exclusion hypothesis assumes a blocking mechanism that operates late, after lexical selection has finished. To delineate between these models, we focused on the distractor frequency effect (i.e., longer picture naming latencies in the context of low-frequency compared to high-frequency words) and measured ERPs concurrently. Behaviorally, the distractor frequency effect was replicated. In the ERPs, three effects were found. One effect occurred very early and is interpreted as an effect of low-level visual feature processing. The two other effects occurred after lexical access and are thus in line with the response exclusion hypothesis.