•Measurable changes detected in swallowing function in 12 months
•Decline in function observed at three anatomical sites considered important for safe swallowing
•Individual anatomical sites may be precursors to widespread functional decline in swallowing
•Subtle but apparently genuine changes in speech occur in HD before clinical diagnosis.
•Speech changes in prodromal individuals are largely characterised by timing deficits.
•Limited longitudinal data restricts capacity to predict HD evolution using speech.
Article highlights
Dysarthria, a neuromuscular speech disorder, can be the first and most prominent manifestation of PD.
Alongside changes in speech, PD is associated with impaired morphosyntactic, lexical-semantic, and high-level language comprehension and production.
Pharmaceutical and surgical interventions for PD may improve certain modalities of speech production, but effects vary between individuals.
Longitudinal research designs are needed to evaluate the complex interplay between motor speech, language, and cognition.
Speech acoustics may serve as a valuable proxy marker of PD ‘risk’, disease progression and treatment efficacy.