A patient shows a substantial language disturbance. Before revealing the answer, decide what distinguishes central aphasia from receptive aphasia.

Ask whether both comprehension and production are affected together, with disturbed grammar and paraphasic errors, or whether the disturbance is chiefly one of comprehension with production relatively preserved. Central aphasia differs from the purely receptive or purely expressive aphasias by affecting both comprehension and production together, rather than one predominantly, with the presence of paraphasic errors alongside disturbed grammar a distinguishing combination of features. Receptive aphasia, by contrast, is a category in which the chief difficulty lies in understanding language, whether spoken or written, with speech production itself relatively preserved, at least in its mechanical aspects, and comprises three specific named sub-types: pure word deafness, agnostic alexia, and visual asymbolia. Whether the disturbance is combined and affects grammar in production as well as comprehension, or is chiefly confined to the comprehension side with production largely preserved, is the key distinguishing feature.