Isolated infarction in the territory of the inferior division of the right middle cerebral artery (MCA) is often associated with subtle clinical features. Sensory aprosodia, a disorder of emotional speech (affective prosody) with impaired prosodo-affective comprehension and repetition (but relatively spared expression) and added impairment of identification of emotional gesturing, has been advanced as a potential clinically useful marker for such lesions. We examine this hypothesis in a prospective serial study of native Anglophones with a recent initial unilateral cerebral infarction demonstrated on CT. There were four patients with inferior divisional infarctions of the right MCA among 42 with infarctions involving the MCA territory (27 right, 16 left). Sensory aprosodia was present acutely in four patients: two inferior divisional right MCA lesions, one more extensive right MCA lesion (with neurologic signs consistent with predominant inferior division of right MCA impairment), and one left MCA infarction. At approximately 20 days postinfarction, there were three patients with sensory aprosodia, including two with inferior divisional right MCA lesions and another with superior divisional right MCA infarction. No healthy controls or lacunar infarction patients showed this profile. We conclude that sensory aprosodia (1) is identifiable with standardized, objective methodology, (2) is an acute marker of inferior divisional infarction in the right MCA territory, (3) is less specific several weeks after infarction, and (4) is not associated with lacunar infarction.