Eigenpoll : Cognitive improvement : B group vitamins

More info - http://en.wikipedia.org/wiki/B_vitamins

B vitamins are a group of water-soluble vitamins that play important roles in cell metabolism. Though these vitamins share similar names, research shows that they are chemically distinct vitamins that often coexist in the same foods. In general, supplements containing all eight are referred to as a vitamin B complex. Individual B vitamin supplements are referred to by the specific name of each vitamin (e.g., B1, B2, B3 etc.).

Vitamin B1 (thiamin)
Vitamin B2 (riboflavin)
Vitamin B3 (niacin or niacinamide)
Vitamin B5 (pantothenic acid)
Vitamin B6 (pyridoxine, pyridoxal, or pyridoxamine, or pyridoxine hydrochloride)
Vitamin B7 (biotin)
Vitamin B9 (folic acid)
Vitamin B12 (various cobalamins; commonly cyanocobalamin in vitamin supplements)