Yes, learning another language has been shown to have cognitive benefits, especially as seen in dedicated, professional translators or interpreters. Nonetheless

Yes, learning another language has been shown to have cognitive benefits, especially as seen in dedicated, professional translators or interpreters. Nonetheless, these facets have been shown to come from practice. Intellectual rigour is rigour nonetheless, just make it varied. You could say the same things about learning a new instrument, hobby, or skill.