This TED talk is a little over 20 minutes long, but believe me, it is worth it.
I learned a long time ago to never listen to anyone when they say something isn't possible - most especially "scientists." They're not gods.
I've always been taught your brain shrinks with age. Then I was taught connections between neurons are forming all the time. Then I was taught new brain cell do form. In other words, our brains are plastic our entire lives. While they're not totally plastic, they are plastic within certain wide parameters.
Arthur C. Clarke said three things I always keep in mind:
"When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong."
"The only way of discovering the limits of the possible is to venture a little way past them into the impossible."
"New ideas pass through three periods: 1) It can't be done. 2) It probably can be done, but it's not worth doing. 3) I knew it was a good idea all along!"