Telencephalic Specialization and Hemispheric Plasticity in Functional Language Compensation: Clues from Neuropathology

Abstract

This article addresses the potential of the right cerebral hemipshere of the human brain to functionally compensate language functions. It reviews cases of left hemispherectomy in intractable epilepsy, and cases of gliomas, early brain damage, arteriovenous malformations, stroke, and hemihydranencephaly. Psycholinguistic and neuroanatomical data are considered from the literature to address the question, to what extent can the right hemisphere produce and understand language, as well as the underlying neuroimaging denominator. It appears that a homologous network ensues, not only in patients subjected to hemispherectomy, but in cases of other forms of brain damage. The ability of the right cerebral hemisphere to take over language functions strengthens the meaning of plasticity in the central nervous system; at the same time, certain questions are raised regarding the importance that has been attributed to specialization and the localization of neurocognitive functions.