Structured Therapy for the Enhancement of Purposeful Speech (STEPS): A Step in the Right Direction to Treating Formal Thought Disorder in Schizophrenia

Abstract

Disordered speech has long been recognized as one of the core features of schizophrenia; it is stable across the course of the disorder, and has been identified as a rate limiter of functional outcome (e.g., social skills, scholastic achievement, vocational success). While much of the recent research on thought disorder has focused on the mechanisms behind disordered speech, we have observed a very limited transfer to clinical applications that promote gains in communication skills. The purpose of this study was to evaluate the efficacy of a novel treatment, Structured Therapy for the Enhancement of Purposeful Speech (STEPS), based in behavioural learning principles, to increase goal-directed speech in individuals with schizophrenia. The current study is one of the first to evaluate an intervention specifically aimed at increasing the core symptom of disorganized speech and evaluating change across multiple indicators of discourse. STEPS is based in principles of operant conditioning, wherein sessions take place three times per week for a total of three weeks. In a single-case multiple baseline design, participants (N=3) received positive reinforcement for engaging in goal-directed speech and directive feedback for committing speech errors, thereby increasing or decreasing frequency of that behaviour, respectively. Participants were assessed before, during, and after treatment on a series of thought disorder and speech coherence measures. Primary outcome measures included change in frequency of communication errors within sessions over the course of treatment and severity of thought disorder on standard disorder measures at three assessments points. Participants demonstrated a significant reduction in number of communication errors across unstructured conversations and structured storytelling components such that all participants engaged in significantly more goal-directed communication during treatment sessions compared to baseline performance. Furthermore, all participants were rated as expressing less severe disconnected speech according to a gold-standard measure of thought disorder. Effective communication is central to successful social interactions from building new interpersonal relationships, advocating for oneself to medical professionals, to demonstrating appropriate skills during interviews. The results of this study suggest that this symptom is amenable to change and can be treated in order to promote real-world functional gains.