However, the rate at which that aging occurs varies and depends on a person’s cognitive reserve—the brain’s ability to counteract the effects of age-related brain damage and maintain optimal performance.

This reserve accumulates throughout a person’s life, as the brain strengthens neural networks in response to various external stimuli. The more complex the neural networks, the greater a person’s cognitive reserve and the milder the age-related changes.

Cognitive reserve has already been shown to be influenced by exercise, diet, career, leisure habits, educational level, socioeconomic status, and several other factors.

In addition, the researchers looked at the effect of bilingualism on brain function in older adults, studying 63 adults aged 60 and older. The participants were healthy and had no history of psychiatric or neurodegenerative disorders.

However, they had to have at least partial knowledge of a second language. Before the experiment, all participants completed a questionnaire that examined their cognitive reserve. They also had to indicate how long they had been speaking a second language, how often and where they used it, and how fluent they were in this language.