Language in people with cervical dystonia: Evidence of grammatical and specific semantic deficits

Background: Although historically considered a motor disorder, cervical dystonia (CD) may present with subtle cognitive impairments. Basal ganglia dysfunction in other neurological conditions can lead to language impairments. Language in people with CD (pwCD) remains unexplored. Objectives: The study aimed to explore phonological, grammatical, and semantic language abilities in pwCD compared to healthy controls. Methods: 19 pwCD and 20 control participants completed the Object and Colour subtests of the Rapid Automized Naming Task (RAN), the Test for Reception of Grammar-2 (TROG-2), and a lexical decision task with a masked priming paradigm that compared reaction times to words varying according to two factors-hand relatedness (hand-related, non-hand-related) and word category (verb, noun). Results: Compared to controls, pwCD were less accurate at grammatical comprehension on the TROG-2 (p < 0.05, n² = 0.15). There were no significant differences between pwCD and controls in phonological retrieval, as measured by the RAN. PwCD demonstrated an overall reduced priming effect for all words, however, there is some evidence in our data that this may be more pronounced for hand-related words. Conclusion: Language deficits should be considered an area of future research in pwCD. These findings support the role of the motor system in language.