There is a deep relation between a second language you learn (i.e. how it is being learned) and the functionality of your brain. Most of the researches conducted in the past concentrated on the effects or benefits of bilingualism.
But, recent studies focus on the question that ‘is bilingualism really advantageous or not?’ Researchers of today are discovering the diverse facets of bilingualism, so that they could better understand the individual effects.
Additionally, a study has been conducted, which highlighted the effects of ‘listening’ and ‘speaking’ (two basic ways in which an additional language is generally used) a second language over the brain. The researchers used DTI technique, i.e. diffusion tensor imaging, using which they measured the differences in the white matter between English monolinguals and Spanish-English bilinguals in US. They also analyzed the effect of speaking and listening to their second language on the brain’s white matter.
It was found that speaking the second language was related to higher FA, while listening was related to lower RD. They also found that bilingual people, who had minimum four years of immersion in the United States, had almost similar levels of white matter, as with the monolinguals.
The bilingual people, who had minimum two years or less years of immersion in the US, were more likely to show differing patterns from the monolinguals. The results showed that bilingualism is one of different factors that affect the functionality of the brain. According to the research, Bilingualism is definitely an advantage. But, the question as to how it actually affects the brain is a topic that needs more research.