wernicke's aphasia

Meaning: Wernicke's aphasia is a loss of language comprehension caused by damage to Wernicke's area, in the posterior superior temporal gyrus, usually of the left hemisphere. This region links word sounds to meaning. Patients speak fluently with normal rhythm, but the content is often nonsensical, with wrong or invented words (sometimes called word salad). They often seem unaware of the errors, and they struggle to understand others and to repeat phrases.

On the MCAT: A passage describes a patient who speaks smoothly but incoherently and cannot follow commands. You must name the damaged area or the type of aphasia. Questions pair it with Broca's area in the frontal lobe and with the arcuate fasciculus, the fiber tract joining the two. Damage to that tract gives conduction aphasia: fluent speech, fair comprehension, but poor repetition.

Common confusion: Students swap Wernicke's and Broca's, or assume that fluent speech must be meaningful. Broca's aphasia is halting, effortful speech with comprehension largely preserved. Wernicke's aphasia is impaired comprehension with fluent, empty speech. Aphasia is also a disorder of language itself, not of the muscles used to produce speech.