Global aphasia, results from damage to extensive portions of the perisylvian region of the brain.

These patients had lesions in the anterior perisylvian region (now known as Broca's area), and produced halting and labored speech, lacking in function words and grammar.

Employing various experimental approaches and paradigms (e.g., the detection or judgment of rhymes, nonword reading, and implicit reading), these studies have localized dysfunctional phonological processing in dyslexia to left-hemisphere perisylvian regions.