Although our genes do play a role in if we acquire certain degenerative diseases such as Alzheimer's, the brain is a powerful organ, and feeding it optimum fuel or "brain food" is proven to keep it performing at it's optimum level.
You may have heard about "functional foods." Nutritionists and marketers use this term to describe foods that go beyond the basics of supplying nutrients to the body and appear to help ward off and combat certain chronic illnesses.
Prenatal exposure to PBDEs interferes with neural development in experimental animals. Rats exposed to flame retardants during fetal development have a weakened ability to strengthen synaptic connections.