Learning a new language, instead of using Luminosity, et al., is like eating a healthy diet, instead of taking supplements. Check out this article about one person’s experience with learning a new language in late middle age.
And if you want to study a new language, here’s a completely free way to do it, and you can help translate the internet, too. I’ve been using Duolingo for about a month. The website is great and I can almost feel the new neural connections.