The Bilingual Brain: Brain Processes During Language Acquisition

This work is a study on language acquisition, brain processes involved during its acquisition and bilingualism. The aim of this research is to better understand how two languages are learning simultaneously, so that we can be better prepared to assist children during linguistic acquisition, as well as to support the teacher and family through theoretical foundation. Aspects such as the cortical organization of language, differences between the bilingual brain, compared to the monolingual brain, and influence of social interaction on linguistic learning are explained in this work to provide a broad view of bilingual language acquisition. For this study, we chose to use the bibliographic research of foreign literature, because not enough materials were found in the Portuguese that covered the areas of study contemplated. The results show how the brain processes language acquisition, shows the difference between learning two languages simultaneously, and sequentially, and presents how social factors and language are associated.


INTRODUCTION
Language acquisition is a very complex process that involves numerous cognitive, behavioral and social aspects. Over the centuries, scholars have tried to formulate theories that explain universally. According to him, all children, in all cultures, become fluent in their native language: Language acquisition is an age-sensitive process, which results from maturational and neuroanatomical changes, still poorly understood. (HAGEN, 2008) (own translation).
Hagen points out that Lenneberg's studies  on language loss in children contributed to the creation of the Critical Period Hypothesis, which states that around the first year of life, until adolescence, the human brain is prepared to acquire language without requiring special instructions, provided that the child is exposed to a rich linguistic environment. Its statement is based on a study done with children who suffered damage to the left hemisphere of the brain in its preverbal phase, and who had no significant damage thereafter.
According to the author, the reason why the human brain is better prepared to learn languages in the early years of life is a matter of physical and behavioral evolution. He likes the needs of a wildebeest cub to a human baby, explaining that a wildebeest cub, because it is easy prey, needs to learn how to move quickly, which occurs almost immediately after delivery. A human baby, born in a socially welcoming environment, depends on language to socialize and survive, which justifies the fact that it is among the first cognitive traits to emerge in childhood.
Hagen (2008) also states that the reason why adults have more difficulty acquiring a new language dates back to the Paleolithic period. The author points out that for a child to learn a language, it usually takes three to four years, and if we consider the culture of nomadic hominids, firstly they would not have the opportunity to learn a new language because they do not have enough time to show exposure to a new language, and secondly, because they have a very short life expectancy , of about 35 years of life, learning a second language in adulthood would be useless: Archaic humans had little opportunity to learn anything during adulthood, simply because adulthood did not last much longer than childhood and adolescence. (HAGEN, 2008) (own translation).
For Hagen, in a scenario like the one mentioned above, the brain's ability to learn a new language during adulthood, with the same speed and efficiency as a child learning his mother tongue, would be of no use, so it was not a skill that evolved universally in the human brain.
The Bilingual Brain: Brain Processes During Language Acquisition www.nucleodoconhecimento.com.br Hagen (2008, p.48) also presents that among the community of educators, there are advocates that the Critical Period Hypothesis does not exist, arguing that the brain is not restricted to a critical biological period, but to social and behavioral factors. For them, issues such as children being more uninhibited than adults, being more motivated to learn and more open to new interactions than adults, is what makes them more successful in learning a new language. Hagen counters these statements, noting that there are no empirical studies that support these ideas, as well as giving examples of adults who, however motivated to learn, however uninhibited, are still no match for children in language acquisition, in the same way that shy and introverted children still have more success in language acquisition, even if compared to motivated and outgoing adults.
While the Critical Period Hypothesis continues, in a way, controversy in educational and social studies, among the scientific community in general -and among the medical community in particular, in which facts about age and issues of loss and recovery of language impose on decisions on how to deal with serious medical conditions -it is accepted without debate. (HAGEN, 2008, p. 49 -own translation).
For Hagen, the need to learn a language during adulthood is still very recent in our evolutionary history to affect our brain architecture, and seen from this perspective, the acquisition of mother tongue by children, and acquisition of a new language by adults, is no longer a mystery, as it seemed in the past, but actually fits perfectly into the mosaic of the theory of evolution.