Pragmatic language production deficits in Parkinson’s disease

This study examines pragmatic language production deficits in people with Parkinson’s disease (PD). Participants (PD and non-PD) were interviewed and their responses coded for degree of informativeness. PD participants were more under-informative than non-PD participants. Response underinformativeness was associated with decreased executive control, mental status, and speech act comprehension measures. However, both speech act priming and utterance informativeness were strongly related to a measure of executive control, and when this variable (i.e., Stroop performance) was controlled, the correlation between speech act priming and utterance underinformativeness was no longer significant. It appears, then, that executive control deficits are related to the ability to comprehend and produce conversational utterances.