All B Vitamins can be considered memory boosters. B6, B12 and Folic Acid are all known to protect the brain cells and improve memory. B Vitamins are found in bread, whole-grain cereals, egg, milk, potatoes and bananas among others.
Antioxidants found in berries, citrus fruits and green leafy vegetables are also good for improving your brain function.
You can refer to my hub - 3 Quick tips to improve your Brain for more information.