I am and have always been convinced that ANYONE can do mathematics if they have the proper motivation, interest, and access to good mentors and training material, at least to the levels found up to and including the first year in college. I believe that ineffective education and cultural and societal biases are reasons why mathematics education has a mystique about is as something less than the primer coat of all higher level thinking.
So articles on studies like that mentioned here in a Scientific American article
To me, the findings are not surprising. It just seems perfectly natural that a person's motivation to learn a skill is extremely important to their ability to master it. More important than intelligence? Ahhh.... Read the article.