SOURCES:
1. According to the neuropsychologist, Eric Lenneberg, in his book Biological Foundations of Language, 1967, the capacity to learn a language is indeed innate, and, like many such inborn mechanisms, it is circumscribed in time. If a child does not learn a language before the onset of puberty, the child will never master language at all. This is known as the critical period hypothesis. This research was from a lecture given by Timothy Mason at the Université of Versailles, St. Quentin. It is available here:http://www.timothyjpmason.com/WebPages/LangTeach/Licence/CM/OldLectures/L3_ExtremeCircs.htm
2. An interview with Dr. Bialystok summarizes her findings. It is available here: http://www.guardian.co.uk/technology/2011/jun/12/ellen-bialystok-bilingual-brains-more-healthy
The NY Times also profiled Dr. Bialystok, which is available here:
3. According to Dr. Wilder Penfield and Dr. Lamar Roberts, Co-Authors, Speech and Brain Mechanisms, the human mind retains a ‘functional plasticity’ for a period of time that lasts from ages 3 to 12. This biological flexibility makes it the optimum time for language learning. More details can be found here: http://en.wikipedia.org/wiki/Critical_period_hypothesis
4. The American Psychological Association studied bilingual speakers. Brain-imaging research has shown that when people switch to another language, their brains make constant use of their executive control network, which involves the dorsolateral prefrontal cortex, anterior cingulate cortex, Broca’s area and the basal ganglia. Working out those brain areas may make these people better able to perform other activities that require switching, such as visual searches where people are asked to find the incongruent image or pattern. The study was summarized on the APA website: http://www.apa.org/monitor/2010/04/language.aspx
5. According to Dr. Laura-Ann Petitto of Dartmouth College, children who have been exposed early to a second language possess an overall "cognitive edge." Numerous studies have also linked language education to higher scores on many standardized tests. A synopsis of the work can be found here: http://www.early-advantage.com/articles/learningtoread.aspx
Additional details about Dr. Petitto’s work on bilingualism can be found on the Society for Nueroscience website here: http://www.sfn.org/index.aspx?pagename=news_11112003a
