Right hemispheric neglect is most commonly due to infarction of which artery territory?

• A. Anterior cerebral artery infarction
• B. Basilar artery infarction
• C. Posterior cerebral artery infarction
• D. Middle cerebral artery infarction

Answer: (D)

Hemispatial neglect from a right-hemisphere stroke most often arises when the parietal attention networks are damaged, and those networks are predominantly supplied by the middle cerebral artery. The right MCA covers the lateral surface of the right hemisphere, including the parietal lobe and the temporoparietal junction, which are crucial for orienting attention to the contralateral space. When this area is infarcted, patients neglect the left side of space because the brain’s ability to integrate sensory input and direct attention there is disrupted.

Infarcts of the anterior cerebral artery affect medial frontal and parietal regions and typically produce contralateral leg weakness and abulia rather than neglect. Basilar artery strokes involve brainstem or cerebellar structures with different clinical pictures. Posterior cerebral artery infarcts impact the occipital and inferomedial temporal regions, often causing visual field defects or visual memory issues rather than the classic neglect syndrome.