Brain Structures in Verbal Communication: A Focus on Prosody

Abstract

Human communication is made up of three domains: speech, language, and pragmatics, which can be fully specified as a set of rules, units, and practices. Prosodic function spans these domains. Neurolinguistic studies utilizing an array of disparate techniques reveal that many parts of the brain are required for normal communicative function. Speech and language are largely lateralized to the left cerebral hemisphere, while pragmatic competence appears to require an intact right hemisphere. Familiarity agnosias have been associated with right hemisphere dysfunction, leading to an explanation for preserved familiar proper noun recognition in severe aphasia. This model pertains to the adult brain; due to the poorly understood phenomenon of cerebral plasticity, laterality of function in children is established weakly and slowly. The basal ganglia may subserve well-known phrasal structures such as that seen in “automatic speech,” and some kinds of prosodic competence, both in production and perception. A thorough model of language and the brain takes into account two horizontal and one vertical dimension: the left-right dimension of hemispheric model differences; the anterior-posterior dimension reflecting sensory and motor processes; and the vertical interaction of cortical and subcortical processes. All of these participate crucially in the different domains of communication.