Research has shown that individuals who speak multiple languages tend to have a younger brain age, as estimated by indicators of brain activity.

The study also found that learning a second language at an earlier age and achieving a higher level of proficiency are associated with delayed brain aging.

Dr. Lucia Amoruso and her research team at the Basque Center on Cognition, Brain and Language in San Sebastian, Spain, presented these findings on July 6 (local time) at the Federation of European Neuroscience Societies (FENS) Forum 2026 held in Barcelona, Spain.

Researchers from Chile, Argentina, and Ireland also participated in the study.

The human brain contains an average of 86 billion neurons, forming between 100 trillion and 1 quadrillion synaptic connections, which serve as pathways for signaling between neurons and other cells. As people age, these connections tend to weaken, often leading to a decline in memory and cognitive processing speed.

The research team analyzed the relationship between multilingual experience and brain connectivity in residents of the Basque region of Spain.

In this region, many people use two or more languages, including Spanish, Basque, French, and English.

The researchers first created a brain aging clock by measuring the brain activity of 728 individuals with varying ages and language abilities using magnetoencephalography (MEG).

MEG measures the minute magnetic fields generated when brain cells are active.

The team then used artificial intelligence (AI) to calculate normal levels of brain connectivity by age and compared the actual age and estimated brain age of a separate group of 144 individuals.

This second group was composed of an equal number of people who spoke one, two, three, and four languages, respectively.

The results showed that the brains of those who spoke two, three, and four languages were 6, 7, and 13 years younger, respectively, than those who spoke only one language.

"Simply put, people who speak more languages tend to have brains that look younger than what would be expected for their actual age," Dr. Amoruso explained.

She added, "The effect was not just related to the number of languages spoken. Higher language proficiency and earlier acquisition of a second language were also associated with more delayed brain aging. This suggests that multilingual experience acts on a gradient. It is not just a matter of whether you are bilingual or not, but a matter of the depth and duration of language experience."

The research team stated that they accounted for factors such as age, gender, and education level of the participants, but cautioned that the potential influence of other factors that could affect the brain, such as lifestyle or social engagement, cannot be ruled out.

The team plans to apply similar analyses to patients with neurodegenerative diseases, such as Alzheimer's, where brain aging and resilience are critical. They also intend to examine whether speaking languages that are very similar to each other has a greater impact on the brain.

Regarding the study results, Professor Christina Dalla of the National and Kapodistrian University of Athens said, "This study suggests that learning a second, third, or fourth language can help our brains stay younger for longer, and the earlier you start, the better."

She emphasized, "There are many good reasons to learn another language at any age. There are social reasons, cultural reasons, and reasons for brain health. Therefore, even if it is difficult, language learning should be supported in schools and throughout life."

Professor Dalla, a neuroscientist, is the chair of the FENS Forum Communication Committee and was not involved in this study.

Some suggest that caution is needed when interpreting the results. Professor Eef Hogervorst of Loughborough University acknowledged that the study suggests multilingualism is linked to better brain resilience, but noted, "It may be that people who speak multiple languages practice healthier lifestyles or have better access to other protective environments and activities, such as reading, lifelong learning, or playing musical instruments."

(Photo: Provided by Nature Aging, Jason Rothman et al., Yonhap News)