Ana Inés Ansaldo, a researcher and professor, and her team have conducted research comparing brain connections in monolingual and bilingual adults to see if there were any difference cognitive performances or processes due to to their language abilities. They have discovered that knowing a second language fluently does in fact influence different ways of processing, one which saves the individual mental resources.
Ansaldo and her team analyzed two brain areas that involved visual and spatial information processing on their participants. They found that when their participants were asked to do a task that focused on a certain type of information while ignoring another, the monolingual participants had a larger brain circuit with a number of connections going on at the same time. On the other hand, the brains of bilingual participants had a smaller circuit.
As this difference did not impact the results between the monolingual and bilingual participants, it suggests that bilinguals are able to use less amount of processing and resources to arrive at the conclusion. Thus, bilinguals have a cognitive benefit of having more centralized and specific connections, which saves them time and mental energy.
Yet, that's not all! Bilinguals also have the advantage of having all these connections occurring in areas of the brain that are not in the frontal lobe region, an area that is vulnerable to aging. This could help explain why bilinguals are better at fighting off signs of cognitive aging or dementia.
Source material from Science Daily