Scientists Rank Foreign Languages by Their Benefit for the Brain

An international team of researchers, with the participation of scientists from the HSE Institute for Cognitive Neuroscience, studied how the choice of a foreign language affects human cognitive abilities. It turns out that languages greatly differing from one's native language stimulate cognitive function at the initial stage of their study, while those similar to the native language have a delayed effect and help the brain work more efficiently at a higher level of proficiency in a foreign language. The results of the study have been published in the journal Bilingualism: Language and Cognition.

Aging cannot be prevented or stopped, but it can be slowed down. The speed of development and the onset time of age-related changes in the brain depend on a person's cognitive reserve—the brain's ability to resist the effects of aging and maintain an optimal level of functioning.

Cognitive reserve can be compared to a savings account in a bank: throughout life, deposits are made from various sources—education, professional activities, lifestyle, nutrition, and others. In old age, when the brain's resources are insufficient to continue customary activities, it gradually begins to use the funds in the cognitive reserve account. The more a person has been able to accumulate throughout life, the longer the brain can use these resources and compensate for its gradually diminishing abilities.

Studies have shown that learning and using foreign languages also contribute to the formation of cognitive reserve and help smooth the aging process. Scientists suggest that this occurs due to the close connection between bilingualism (proficiency in two languages) and the brain's executive function, which is responsible for memory, attention, and language control. Different languages are simultaneously activated in the brain, and bilingual individuals are constantly forced to quickly and accurately switch from one language to another, thus training the cognitive control system.

Researchers from the HSE Institute for Cognitive Neuroscience, together with their foreign colleagues, for the first time, have traced how bilingual brains change depending on how native and non-native languages differ from each other, or in other words, on the linguistic distance between them. Closer languages are easier to learn because their grammatical structure and lexical-semantic structure are similar to the native language. For example, the linguistic distance between Russian and Belarusian is much smaller than between Russian and Chinese.

The study involved more than 60 volunteers from different countries over the age of 60 without psychiatric or neurological disorders. All of them had a command of English as a foreign language.

The experiment was conducted online and consisted of several parts. First, participants were asked to fill out a questionnaire to determine their socio-demographic parameters, such as gender, age, marital status, frequency of sports activities, leisure activities, level of education, number of friends and social circle, among others. All these factors influence the formation of cognitive reserve. Participants also underwent testing to determine their level of proficiency in the foreign language and indicated how long they had been studying it and how often they used it. The linguistic distance between the native language and English was calculated by a special program on the eLinguistics website.

Next, the participants performed the Eriksen flanker task, which is traditionally used to assess attentional concentration. Participants see a series of five arrows, with the central arrow being the key stimulus. The flanker arrows may point in the same direction as the key stimulus, in the opposite direction, or instead of flanker arrows, there may be other objects (for example, dashes).

As a response, the participant must indicate the direction of the central arrow as quickly as possible. Typically, responding to the opposite direction of the arrow requires more time and activates the inhibition function, which kicks in for bilinguals when they need to choose between languages.

The results showed that for individuals proficient in languages with greater distance, reaction time to the flanker task with arrows pointing in different directions was better if they had just started learning the second language and had not yet mastered it. Conversely, for individuals proficient in closer languages, a reverse effect was observed—acceleration of reaction time was noted if they were proficient in the second language and had been using it for a long time.

We discovered a dynamic effect of bilingualism on human cognitive functions depending on the proximity of native and foreign languages. Linguistic distance manifests itself differently at the language learning stage and at the control stage. When you are just starting to learn a language, you need maximum effort to memorise new words, grammar, and pronunciation. And the less the language resembles your native one, the more difficult it will be for you in the early stages of learning.

Federico Gallo
Study author, Research Fellow at HSE Institute for Cognitive Neuroscience

However, distant languages are much easier to distinguish and control to prevent the mixing of linguistic systems. Therefore, as soon as a person reaches a sufficient level of proficiency, the beneficial effect of learning distant languages gradually diminishes.

The effect of learning distant languages can be compared to the effect of sports training. When you start training, you see significant changes, muscle mass starts to grow rapidly, but then you start to lose weight instead. Over time the brain similarly gets rid of excess, unnecessary neural connections.

Federico Gallo
Study author, Research Fellow at HSE Institute for Cognitive Neuroscience

In the case of languages with shorter distance, people do not require much effort to learn vocabulary and grammar, but the language control system in the brain must work constantly. The longer you study a close language, the more you train the executive function of the brain, and the better your memory and attention work, which plays an important role in old age.

In the future, the authors plan to continue research in this area and study the influence of linguistic distance on cognitive functions in people proficient in more than two languages.
IQ

June 06