Single-Interval and Rhythmic Temporal Prediction in Cervical Dystonia.

Background: Cerebellar dysfunction disrupts memory-based temporal predictions (TPs), whereas basal ganglia dysfunction affects rhythm-based TPs. Investigating TPs in cervical dystonia (CD) may help to delineate the contributions of subcortical circuits to CD pathophysiology.

Objective: The aim of this study was to explore TP ability in patients with CD compared with healthy control subjects (HCs) and to examine the relationship between TPs and clinical features of CD.

Methods: Twenty patients with CD and 20 HCs completed a TP task. Reaction times (RTs) were measured during TPs under three conditions: rhythmic and single-interval (predictable target onset) and random (unpredictable target onset). RT benefit scores were calculated by subtracting RTs in the random condition from those in predictive conditions.

Results: Our exploratory analysis showed that patients with CD had lower benefit scores than HCs in the single-interval task. In CD, benefit scores in the single-interval task were negatively correlated with Toronto Western Spasmodic Torticollis Rating Scales severity.

Conclusions: Patients with CD exhibited selective impairments in interval-based predictions, suggesting cerebellar involvement in dystonia's pathophysiology. © 2025 International Parkinson and Movement Disorder Society.