Chronic and recreational use of cocaine is associated with a vulnerability to semantic interference.

Abstract

Language production requires that speakers effectively recruit inhibitory control to successfully produce speech. The use of cocaine is associated with impairments in cognitive control processes in the non-verbal domain, but the impact of chronic and recreational use of cocaine on these processes during language production remains undetermined. This study aims to observe the possible impairment of inhibitory control in language production among chronic and recreational cocaine polydrug users. Two experiments were carried out on chronic (experiment 1) and recreational (experiment 2) cocaine polydrug users performing a blocked-cycled naming task, yielding an index of semantic interference. Participants were matched for sex, age, and intelligence (Raven's Standard Progressive Matrices) with cocaine-free controls, and their performance was compared on the blocked-cycled naming task. Chronic and recreational users showed significantly larger semantic interference effects than cocaine-free controls, thereby indicating a deficit in the ability to inhibit interfering information. Evidence indicates a relationship between the consumption of cocaine, even at recreational levels, and the inhibitory processes that suppress the overactive lexical representations in the semantic context. This deficit may be critical in adapting and responding to many real-life situations where an efficient self-monitoring system is necessary for the prevention of errors.