What Do Language Disorders Reveal about Brain–Language Relationships? From Classic Models to Network Approaches

Abstract

Studies of language disorders have shaped our understanding of brain-language relationships over the last two centuries. This article provides a review of this research and how our thinking has changed over the years regarding how the brain processes language. In the 19th century, a series of famous case studies linked distinct speech and language functions to specific portions of the left hemisphere of the brain, regions that later came to be known as Broca's and Wernicke's areas. One hundred years later, the emergence of new brain imaging tools allowed for the visualization of brain injuries in vivo that ushered in a new era of brain-behavior research and greatly expanded our understanding of the neural processes of language. Toward the end of the 20th century, sophisticated neuroimaging approaches allowed for the visualization of both structural and functional brain activity associated with language processing in both healthy individuals and in those with language disturbance. More recently, language is thought to be mediated by a much broader expanse of neural networks that covers a large number of cortical and subcortical regions and their interconnecting fiber pathways. Injury to both grey and white matter has been seen to affect the complexities of language in unique ways that have altered how we think about brain-language relationships. The findings that support this paradigm shift are described here along with the methodologies that helped to discover them, with some final thoughts on future directions, techniques, and treatment interventions for those with communication impairments. (JINS, 2017, 23, 741-754)

Brain, Behavior, and Cognitive Interplay in Disorders of Consciousness: A Multiple Case Study

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An empirical comparison of univariate versus multivariate methods for the analysis of brain-behavior mapping

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A.R. Luria's contribution to studies of the brain organization of language

“…В целом интерпретация А.Р. Лурии мозговой организации речи, т. е. специфического вклада различных областей мозга в речевую систему, продолжает широко использоваться, а его значительный вклад в нейролингвистику общепризнан [83].…”