A 68-year-old man with atrial fibrillation develops sudden right hemiplegia and a right homonymous hemianopia. A few hours later he becomes drowsy. CT shows a large hypodense area in the territory of the left middle cerebral artery. Which additional finding is expected on neurological exam?
- A Right-sided cerebellar ataxia
- B Contralateral (right-sided) Horner's syndrome
- C Global aphasia (if left hemisphere dominant) ✓
- D Internuclear ophthalmoplegia
Correct answer: C. Global aphasia (if left hemisphere dominant)
Explanation
A large left MCA territory infarct encompasses both Broca's area (posterior inferior frontal gyrus, BA44/45) and Wernicke's area (posterior superior temporal gyrus, BA22), producing global aphasia — inability to speak, comprehend, read, or write. Right hemiplegia results from involvement of the motor cortex and corticospinal tract in the precentral gyrus and posterior limb of the internal capsule. Right homonymous hemianopia occurs because the optic radiation passes through the temporal and parietal lobes within the MCA territory.
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.