How Do Autistic Adults Use Syntactic and Prosodic Cues to Manage Spoken Discourse?

Discourse studies investigating differences in the socio-communicative profiles of autistic (ASD) and neurotypical (NT) individuals have mostly relied on orthographic transcriptions, without taking prosodic information into account. However, atypical prosody is ubiquitous in ASD and a more accurate representation of their discourse abilities should also include prosodic cues. This exploratory study addresses this gap by segmenting the spoken discourse of 12 ASD and NT adults using the framework of Basic Discourse Units (BDUs). BDUs result from the mapping of syntactic boundaries on prosodic units, which can coincide in different ways and are associated with different discourse strategies. We hypothesized that the discourse of ASD adults would display more atypical strategies than NT adults, reflecting a 'pedantic' style and more difficulties in managing ongoing discourse. While ASD adults did not produce more discourse units associated with didactic or pedantic strategies than NT adults, they did produce less units associated with strategies of interactional regulation. This study provides initial evidence that multidimensional linguistic units, such as BDUs can help differentiate speech delivery strategies of ASD adults from those of their NT peers, even based on simple prosodic cues like silent pauses.