Avocado is high in the type of fat called monounsaturated fat, which helps increase blood flow and oxygen to the brain. The more blood flow to the brain, the better the memory and thinking abilities.
Apples have been shown to boost brain function, according to a review written by Orange Pippin Assoc.
"Animal research from the University of Massachusetts Lowell (UML) indicates that apple juice consumption may actually increase the production in the brain of the essential neurotransmitter acetylcholine, resulting in improved memory." Visit http://www.orangepippin.com/resources/health/benefits-of-apple-juice-on-neurotransmitter-affecting-memory (for entire article)
Dark Chocolate reduces inflammation and has antioxidant effects on the brain, preventing neurological disease.
Green Tea contains EGCG, which protects the brain and decreases the amount of plaque build up
Blueberries contain many nutrients which reverse age-related functioning of the brain, helps improve learning, motor skills and vision
Sources: Ancient Traditions Natural Medicine & Orange Pippin Ltd.