Using speech entrainment to predict conversational outcomes in autistic adolescents - ABSTRACT Autistic and neurotypical individuals often struggle to engage in successful conversations with one another. Yet there are currently no valid methods for quantifying conversational outcomes for autistic individuals and their conversation partners. Accordingly, it is extremely difficult for clinicians to identify difficulties and establish strategies to increase conversational success. This is particularly detrimental during adolescence, a period of life when conversation plays a markedly pivotal role in establishing friendships and emotional closeness with others. Speech entrainment provides a valid and quantifiable measure of conversational outcomes. Speech entrainment is the tendency for interlocutors to modify their speech behaviors to align with the behaviors of their conversational partner. Key here is the extensive body of theoretical and empirical research documenting a robust relationship between speech entrainment and real-world metrics of conversational success. Speech entrainment has been linked to conversational efficiency and quality, better rapport, and stronger interpersonal relationships. The majority of this research has focused on adults. However, in our previous NIH-funded research, we created and validated a robust methodology for measuring entrainment in neurotypical adolescents and demonstrated its ability to predict tangible metrics of conversational success. Nevertheless, an understanding of entrainment in autistic adolescents is lacking. In our previous work, we demonstrated differences in the entrainment patterns of autistic and neurotypical adults in highly controlled laboratory settings. Pilot data collected for this project from 28 dyads in naturalistic peer-based conversations suggests similar differences in adolescence as well. However, beyond this data, research in this area is virtually nonexistent. Thus, addressing this gap represents the requisite first step towards our ultimate goal—to develop a valid and objective measure of conversational success that can be used to optimize treatment outcomes for autistic adolescents. Here, we propose an investigation focused on gaining a comprehensive understanding of entrainment in autistic adolescents and their communication partners and determining the relationship between entrainment and real-world metrics of conversational success in these individuals.