Being Bilingual Protects Against Some Age-Related Cognitive Changes

"WASHINGTON — Most will agree that two heads are better than one in solving problems. The same logic may be true for language and retaining cognitive processes as we age. Being fluent in two languages seems to prevent some of the cognitive decline seen in same-age monolingual speaking persons, according to the findings of a study appearing in this month’s journal of Psychology and Aging."

Reading this brought to mind the blessed Prophet, upon him be Allah's peace and blessings, who was "given mastery of language"
"He learned the dialects of the Arabs and would speak to each of their communities in their own dialect and converse with them in their own idiom." From Ash-Shifa of Qadi 'Iyad, tras.by Aisha Bewley. Section 5, Chapter 2.