"We found that people who eat chocolate at least once a week tend to perform better cognitively," said Elias. "It's significant—it touches a number of cognitive domains."
Yes! I would gladly volunteer for this study.
Why exactly eating chocolate is associated with improved brain function Crichton can't say with absolute certainty. Nor can Elias, who admits that he expected to observe the opposite effect—that chocolate, given its sugar content, would be correlated with stunted rather than enhanced cognitive abilities. But they have a few ideas.
No lie, in college I had heard that eating dark chocolate helped one's memory in the short term so I religiously ate some the night before any final exam. That doesn't explain me almost failing freshman chemistry but may explain why I did well in everything else.