Objective: Compare StartReact paradigm in cervical dystonia (CD) patients compared to matched healthy participants.

Background: The voluntary response to vestibular stimulation is enhanced in CD patients compared to healthy controls. Moreover, the vestiblo-colic reflex is reported to be altered in CD patients. The possible pathway integrating vestibulo-voluntary integration could be through vestibulo-reticulospinal pathways. Therefore, abnormalities in the reticulospinal tract, tested using a StartReact paradigm, might be observed in CD.

Methods: The StartReact response was estimated in patients with CD and healthy participants. Here, we measured EMG from affected sternocleidomastoid muscle. The participants were instructed to turn their head to the opposite direction, in response to a LED cue. They were seated comfortably in a quiet and dimly illuminated room. The LED (60 times) was accompanied by quiet sounds (20 times) and loud sounds (20 times) at random. The difference of latencies in response to quiet sound (visual-auditory response time/VART) and loud (visual-startle response time/VSRT) sound was taken as the primary measure of StartReact.

Results: 11 healthy participants and 9 CD patients were investigated in this cross-sectional study. The VART-VSRT was 60 (+/- 41) ms in healthy and 69 (+/- 55) ms in CD patients (p 0.65). The VSRT, VART and visual response time was significantly shorter in CD patients compared to healthy participants.

Conclusions: Disinhibition was not apparent in a StartReact paradigm in CD patients. Therefore, reticulospinal connections are likely to be unaffected in CD patients. The observed vestibular defect could be either through direct vestibulospinal output or through a defect in the central processing.

« Back to 2018 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/start-react-paradigm-in-patients-with-cervical-dystonia/