What term describes loss of balance in a patient with brainstem or cerebellar injury?

• A. Dystonia
• B. Aphasia
• C. Agnosia
• D. Ataxia

Answer: (D)

Ataxia describes loss of coordination and balance that results from cerebellar or brainstem dysfunction. The cerebellum normally coordinates posture and smooth, precise movements; when it’s injured, a person may have an unsteady, wide-based gait, difficulty with rapid alternating movements, and problems with aiming movements like finger-to-nose. Dystonia involves involuntary muscle contractions causing twisting postures, not primarily balance loss. Aphasia is a language impairment, and agnosia is trouble recognizing objects despite intact senses. So the balance impairment specifically points to ataxia.