Language Functions and Brain Organization explores the question of how language is represented in the human brain. The discussions are organized around the following themes: whether language is a mental organ or a mental complex; the brain base for language; the requirements of a developmental theory of lateralization; and whether brain lateralization is a single construct. Comprised of 15 chapters, this volume begins with an assessment of the semantic and syntactic aspects of aphasic deficits and how these components can be selectively disrupted by focal brain damage, followed by a review of evidence for hemispheric asymmetries in processing phonological information. The reader is then introduced to pragmatic aspects of communication; the right hemisphere's contribution to language; and right-left asymmetries in the cerebral cortex and their implications for functional asymmetries. Subsequent chapters focus on left-hemisphere language specialization from the perspective of motor and perceptual functions; evidence for hemisphere asymmetry for language functioning in the thalamus; some difficulties in building a brain theory for visual experience; speech lateralization in infancy; and the relationship between cerebral functional asymmetries, maturation rate, and cognitive skills through the mediation of sex chromosomes. The book also considers language dysfunction in dementia and its connection to brain functioning, along with the variations produced in cases of bilingualism and the factors that may be critical for this issue. This monograph is addressed to researchers and students of the neuropsychology of language, whether they call themselves psychologists, neuropsychologists, neurologists, or linguists.