Here is the link to a very interesting set of studies on the brain. I include one paragraph to whet your appetite. Yep, it's about chocolate, but you probably already know what it's gonna say. The other nine paragraphs are equally as important. Go take a look.
"2) Send grandpa a vat of chocolate: Here’s yet another reason chocolate is awesome.
Italian researchers have found that a cocoa drink rich in flavanols–the
antidioxidants found in chocolate–can help sharpen the brains of people
with memory problems. The antidioxidants are believed to protect brain
cells and improve blood flow."