Leveraging entrainment for improving communication in people with Parkinson's disease. - PROJECT SUMMARY/ABSTRACT Neurological disorders are the leading source of disability globally, and Parkinson's disease (PD) is the fastest growing neurological disorder in the world. The gold standard of care for treating dysarthria are behavioral interventions, or “speaker strategies,” that reduce or compensate for the underlying speech deficits to improve listener understandability. The speech of people PD (hypokinetic dysarthria) typically sounds mumbled and rapid, which inform the two primary targets for intervention: clear speech and slow speech. Another speaker strategy involves using simple language. While not directly tied to the underlying speech deficit, it supports the listeners' ability to recognize words, thus compensating for the degraded acoustics. While people with hypokinetic dysarthria demonstrate the ability to use these speaker strategies in the clinic and in controlled research contexts, strategy use does not generalize to their everyday conversations. Here, we proposal to exploit the natural process of entrainment, in which people adapt their speech and language behaviors to align with the same behaviors of their communication partner. This entrainment of behavior has been demonstrated in many different aspects of speech and language, including articulatory precision, speech rate, and word choice. It is also predictive of broader measures of communication success. The purpose of this study is to explore the extent to which, and under what circumstances (clear speech, slow speech, simple language), patients with hypokinetic dysarthria entrain to, or align to the patterns of, communication partners (i.e., confederates) who are intentionally using those strategies. Grounded in the interactive alignment model, we hypothesize automatic entrainment to the speech and language behavior produced by a confederate would facilitate improved communication of the participant with PD, specifically making it easier and more natural for them to use clear speech, slow speech, or simple language in the conversation. We also expect benefits to extend beyond greater use of the strategy, to greater communicative efficiency and conversational satisfaction. This proposal sets the stage for an innovative and much needed extension of dysarthria management to include the communication partner in intervention. Toward that end, 30 participants with mild to moderate hypokinetic dysarthria associated with PD will be instructed to use a designated speaker strategy. They will then engage in a controlled conversational task (Diapix task), which involves collaborative problem-solving, with two different confederates – one who will also use the selected strategy (manipulation), the other confederate will not (control), for a total of 6 conditions. We will assess the impact of strategy use by the confederate (relative to no strategy use) on the participant with PD with regards to quantitative speech and language changes, communicative effectiveness, and conversational satisfaction. This work will tap into the potential of entrainment to facilitate the carryover of speaker strategies to conversation, and thus improve real world communication for people with PD.
