Cultural and linguistic influence on brain organization for language and possible consequences for dyslexia: a review.

Current neuroimaging and neurophysiologic techniques have substantially increased our possibilities to study processes related to various language functions in the intact human brain. Learning to read and write influences the functional organization of the brain. What is universal and what is specific in the languages of the world are important issues. Most studies on healthy bilinguals indicate that essentially the same neural mechanisms are used for first and second languages, albeit with some linguistic and cultural influences related to speech and writing systems, particularly between alphabetical and nonalphabetical languages. Proficiency, age of acquisition, and amount of exposure can affect the cerebral representations of the languages. Accumulating data support the important role of working memory for acquiring high proficiency in the reading of native and second languages. It is proposed that longitudinal studies on second language acquisition are essential and that the specific problems related to second language learning in dyslexic children should have high priority.