Dystonia affects what in the brain?

• A. Basal ganglia
• B. Cerebellum
• C. Cortex
• D. Brainstem

Answer: (A)

Dystonia primarily involves dysfunction in the basal ganglia, a deep-brain motor control network that helps start, scale, and regulate movements. When these circuits misfire, signals to activate or relax muscles become imbalanced, leading to sustained or intermittent contractions and abnormal postures that define dystonia. The basal ganglia work with the thalamus and cortex to shape movement timing and force, so disruption here produces the characteristic dystonic movements. Other regions like the cerebellum, cortex, or brainstem are involved in broader motor control and can influence symptoms, but the classic association and the strongest causal link are with the basal ganglia.