The purpose of language testing is to look for evidence of dysfunction of the hemispheric cortical regions that are involved in the production or comprehension of spoken or written language.

The ability of your patient to understand and produce spoken language should be evident by informal observation during the history and throughout your interaction with the patient. More formal evaluation of language function should be performed when there is a complaint of difficulty with language or speech, or when you suspect a disorder of language from your conversation with the patient during the history. In addition, language function should be tested in any patient with a right hemiparesis to look for evidence of localization of the neurologic process to the cortex.

Language function resides in the left hemispheric cortex in essentially all right-handed patients and at least one-half of left-handed patients. The side of the brain where a patient’s language is located is called the dominant hemisphere.

There are two main areas of the dominant hemisphere that are important for language function: Broca’s area and Wernicke’s area. Broca’s area is located in the inferior frontal lobe, just anterior to the motor cortex, and is involved in the production of language. Wernicke’s area is located in the posterior-superior temporal lobe, near the auditory cortex, and is involved in the comprehension of language.

None.