Language is one of the most important brain functions. It is considered to be among the main instruments of human cognition. Language is also one of the features that differentiates human beings from all other mammals; the modern technologically advanced society would not exist without language. Scientists have investigated the phenomenon of language and the human brain for many years. Nowadays, it is much easier to carry out new studies because of the availability of new methods and apparatus, for example, fMRI which allows to receive more precise information. Scientists conduct experiments not only with people who speak one language but also with bilinguals and polyglots. In this case, such things as the areas of the brain responsible for each language and the mechanism of language switching are just two from the variety of problems faced by the scientists.
Two main questions that have traditionally been taken into consideration by the scientists who dealt with bilingualism were to identify the brain area corresponding for languages representation and to understand the neuropsychological mechanism of switching from one language to another (Hernandez, 2000). Several scientists have conducted various experiments to describe the nature of bilinguals’ language switching mechanism, for example, Hernandez. According to him, the Dorsolateral Prefrontal Cortex plays a very significant role in language switching (Hernandez, 2009). He also distinguishes other brain zones which are involved in the process of language switching, such as the supplementary motor area, superior parietal lobule, and Precental Gyrus. According to Hernandez, there is a strong connection between the ability to speak two languages and inhibitory processing of visual attention. He also found that bilingualism increases inhibitory processing in adult life. Hernandez is convinced that the connection between bilingualism and inhibitory processing is one of the potential fields of study in the future. He believes that inhibitory control is an important thing in the everyday life and it is necessary to compare it in both bilingual and other speakers (Hernandez, 2009).
The second field of future study, according to Hernandez, would be very similar to the hypothesis presented in this research proposal. He claims that, in the literature on bilingualism only the general information about the early and late bilinguals and their mechanisms of language processing can be found. Nevertheless, general statistics suggest that language acquisition may be a question of time and bilingualism is a complicated process. Hernandez also states that bilinguals who have learned the second language may have different somatosensory processing, emotion, and memory. He also bounds his hopes of answering this question to the usage of new apparatus, such as fMRI, and other neuroimaging techniques.
Experiments conducted by Hernandez in 2000 prove that the both languages spoken by bilinguals are not represented in the different areas of brain. He performed an experiment with six English-Spanish bilinguals using behavioral measures and fMRI. Bilinguals who took part in the study demonstrated slower reaction and higher activity in the dorsolateral prefrontal cortex when they were asked to name pictures using two languages in turn instead of one. Hernandez is convinced that this may mean that in early bilinguals the overlapping parts of the brain are responsible for the two languages learned in the early childhood and the switching between these two languages is a part of general attentional system (Hernandez et al., 2000). He also aimed to clarify which brain areas are involved in the process of switching between the two languages. He supposed that they might be the super marginal gyrus or dorsolateral prefrontal cortex. It turned out that none of them is in fact involved.
There is another area of brain which takes part in language switching, according to the research made by Hernandez. This area is dorsolateral prefrontal cortex. Scientists also introduced the idea that the experiment language switching combined with the task switching might influence the brain areas responsible for the process. Another main question raised by Hernandez is whether or not different languages are presented in different areas of the brain. He suggests that fMRI might be unable to detect some minor aspects of brain functioning and some little areas of brain which are responsible for languages. Hernandez is convinced that only the combination of fMRI with other traditional and new methods might help to reach the truth about the representation of languages and the mechanisms of their switching in the bilingual brain.
In the 2001 research by Hernandez et al., the experiment was different from those presented in all other articles written by the same author. Participants were asked not only to name objects on the pictures in English and Spanish but also to name some actions. This was called the within-language switching condition. The central point of research was the comparison between mixed and blocked activation conditions. Hernandez found “increased intensify of activation in the right dorsolateral prefrontal cortex for switching relative to no switching but only in the between-language condition” (Hernandez, 2001). Moreover, he found the “increased area of activation in the left inferior frontal gyrus for the blocked condition” (Hernandez, 2001). According to Hernandez, this means that increased executive function is needed to switch between languages in picture naming. These results might be also explained by the necessity to keep two languages in mind and work with them simultaneously. He also assessed switching between languages in terms of age. The magnitude of switching costs turned out to be different for people of various ages. Hernandez also used cues in his experiment and introduced the concept of different lexical classes. The experiment did not reveal that processing different lexical classes affects different areas of activation. The scientist failed to see any differences in activation for each language in early bilinguals, which proves the hypothesis that early bilinguals demonstrate little difference in activation while taking part in the experiment.
Seven Pinker said that studying a language using neuro-imaging is like using “satellite photos to understand how telecommunication lines are interconnected” (Hernandez, 2009). Hernandez did not agree with this statement, which is quite reasonable because fMRI is a very efficient and promising method that can help to make many important findings in the sphere of neuropsychology in the future.
Moreover, there are a number of open questions in the field of languages and neuropsychology. Scientists have not found out yet how two languages function in the brain of a bilingual; whether they function within the same areas of the brain or within the different ones. One more question is whether children who had moved to some other country in early childhood and learned the language of that country remember their first native language. And there are much more open questions in the sphere of language and brain.
The hypothesis which would be the central point in this research is that the early bilinguals use more automatic mechanisms of switching between the languages than those who learned the second language later in life. If this is true and early bilinguals do not have specific mechanism of language switching, then it may mean that children are more acquisitive when it comes to language learning. This hypothesis has a great pedagogical value, because if it is true, then it is better for parents and schools to encourage children to learn foreign languages from the earlier age than they do it now.