Lexical inhibition after semantic violations recruits a domain-general inhibitory control mechanism.

Abstract

Language processing is incremental. As language signals-for example, words in a sentence-unfold, humans predict and activate likely upcoming input to facilitate comprehension. Prediction not only accelerates understanding but also prompts reassessment in the case of prediction error, fostering learning and refining comprehension skills. Therefore, it is paramount to understand what happens when linguistic predictions are violated-for example, when a sentence ends in an unpredicted word. One theory, which we test here, is that the originally predicted word is actively inhibited after semantic violations. Furthermore, we tested whether this purported lexical inhibition process is achieved by a domain-general mechanism-that is, one that also inhibits other processes (e.g., movement). We combined a semantic violation task, in which highly constrained sentences primed specific words but sometimes continued otherwise, with a motoric stop-signal task. Across two experiments, semantic violations significantly impaired simultaneous action-stopping. This implies that lexical and motor inhibition share the same process. In support of this view, multivariate decoding of electroencephalographic recordings showed early overlap in neural processing between action-stopping (motor inhibition) and semantic violations (lexical inhibition). Moreover, a known signature of motor inhibition (the stop-signal P3) was reduced after this initial overlap period, further suggesting the presence of a bottleneck due to shared processing. These findings show that semantic violations trigger inhibitory processing and suggest that this lexical inhibition recruits a domain-general inhibitory control mechanism. This provides a new perspective on long-standing debates in psycholinguistics, extends the range of a well-characterized cognitive control mechanism into the linguistic domain, and offers support for recent neurobiological models of domain-general inhibitory control. (PsycInfo Database Record (c) 2024 APA, all rights reserved).