[The language area of the brain: a functional reassessment]

Rev Neurol. 2016 Feb 1;62(3):97-106.
[Article in Spanish]

Abstract

Introduction: During the late 19th and early 20th century, a 'brain language area' was proposed corresponding to the peri-Sylvian region of the left hemisphere as concluded by clinical observations. This point of view has continued up today.

Aim: Departing from contemporary neuroimaging studies, to re-analyze the location and extension the brain language area with regard to the different Brodmann areas.

Materials and methods: Using the method known as metaanalytic connectivity modeling seven meta-analytic studies of fMRI activity during the performance of different language tasks are analyzed.

Results: It was observed that two major brain systems can be distinguished: lexical/semantic, related with the Wernicke's area, that includes a core Wernicke's area (recognition of words) and an extended Wernicke's area (word associations); and grammatical system (language production and grammar) corresponding to the Broca's complex in the frontal lobe, and extending subcortically It is proposed that the insula plays a coordinating role in interconnecting these two brain language systems.

Conclusions: Contemporary neuroimaging studies suggest that the brain language are is notoriously more extended than it was assumed one century ago based on clinical observations. As it was assumed during the 19th century, the insula seemingly plays a critical role in language.

Title: Area cerebral del lenguaje: una reconsideracion funcional.

Introduccion. Hacia finales del siglo XIX y comienzos del siglo XX, y basandose en observaciones clinicas, se propuso que existe un 'area del lenguaje' en el cerebro que corresponde, en general, a la region perisilviana del hemisferio izquierdo. Tal idea ha continuado existiendo desde entonces. Objetivo. Partiendo de los estudios contemporaneos de imagenes cerebrales, reanalizar la localizacion y extension del area del lenguaje con relacion a las diferentes areas de Brodmann. Materiales y metodos. Utilizando la metodologia conocida como metaanalytic connectivity modeling, se revisan varios estudios metaanaliticos en los cuales se analizan las imagenes de resonancia magnetica funcional durante la realizacion de tareas linguisticas. Resultados. Se encontro que existen dos sistemas linguisticos diferentes en el cerebro: un sistema lexico/semantico, relacionado con el area de Wernicke, y que incluye un area de Wernicke central (reconocimiento de palabras) y un area de Wernicke extendida (asociaciones linguisticas); y un sistema gramatical, dependiente del complejo de Broca (produccion del lenguaje y gramatica), en el lobulo frontal, y que se extiende subcorticalmente. Se propone tambien que la insula desempeña un papel de coordinacion de estos dos sistemas linguisticos cerebrales. Conclusion. Los estudios contemporaneos de neuroimagen sugieren que el area del lenguaje en el cerebro es notoriamente mas amplia de lo que se supuso hace un siglo basandose en observaciones clinicas. Tal como se consideraba durante el siglo XIX, la insula parece desempeñar un papel critico en el lenguaje.

MeSH terms

  • Brain / anatomy & histology*
  • Brain / physiology*
  • Broca Area
  • Humans
  • Language*
  • Wernicke Area / physiology