Broca's area
Summary
Broca's area is a region of the frontal lobe, in the left hemisphere for most people, that supports speech production and grammar. Damage causes Broca's (expressive, nonfluent) aphasia: effortful, halting speech with comprehension largely preserved, unlike Wernicke's aphasia.
Detail
Meaning: Broca's area is in the inferior frontal gyrus of the frontal lobe, in the left hemisphere for most people, next to motor cortex that controls the mouth and tongue. It supports planning and producing speech and using grammar. Language is left-lateralized in most people, but not all.
On the MCAT: A patient understands questions but answers in short, effortful, telegraphic phrases such as "walk dog park." The answer is damage to Broca's area, causing nonfluent (expressive) aphasia. Questions contrast this with Wernicke's area in the temporal lobe, where damage gives fluent but meaningless speech and poor comprehension. The arcuate fasciculus connects the two; damage to it impairs repeating words (conduction aphasia).
Common confusion: Students swap the two areas. Broca's is production: comprehension is largely preserved and the patient often knows the speech is wrong. Wernicke's is comprehension. Remember Broca = broken speech, Wernicke = word salad. Broca's area is also not the motor cortex itself, so the mouth muscles are not paralyzed.
Sources
- Psychology (Myers)
- Biological Psychology (Kalat)
Written for the MCAT and checked before it was published. For study reference only. Spotted an error? Let us know.