When we studied deficits in the ability to convert the sound waves that hit the ear into speech sounds, we found that strokes that disrupt this process tend to occupy a region of cortex quite close to the primary auditory cortex. This was quite different from the pattern seen regarding disturbances of syntactic processing, where strokes in many areas impaired this function. Thus, putting together the pieces of the puzzle of the how the brain is organized to support language may be a very complex task. The application of new imaging techniques will move research in this area along at the most rapid pace ever known. The language system is connected to other intellectual and motor systems.
People use language to inform others, to ask for information, to get things done, etc.
The mechanisms that trigger language use require motivation and arousal. Functional neuroimaging studies have provided strong evidence that areas such as the frontal lobes and structures deep in the brain, such as the cingulate gyrus, become active during many language tasks. Perhaps these structures are related to the level of arousal needed to activate language processors. Once language use is initiated, it must be regulated in time and monitored. The relevant timing mechanisms may lie in the cerebellum and in subcortical gray matter, which recently have been found to be active during many language functions and to result in language impairments when lesioned.