Choline is a precursor of acetylcholine (a neurotransmitter) and is a vital part of the phospholipid bilayer that makes up the cell membrane. If you administer choline to a newborn or pregnant rat during certain critical periods, the baby rat will often grow up to have a better memory--that is, it'll learn a maze faster and will make fewer mistakes. Foods with high choline include eggs, meat, fish, nuts, legumes, and soy, as well as human breast milk. It's not yet clear whether choline has this effect on humans, too, but it can't hurt to get a healthy dose of choline-rich foods.
Its chemical formula is
HO-CH2-CH2-N+-(CH3)3
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