Since 1947 Support Cognitive Function Gluten, Wheat & Dairy Free Dietary SupplementPhosphatidylcholine is the predominant phospholipid in all cell membranes, including brain cell membranes. It is derived from lecithin. Phosphatidylcholine contains choline, a required precursor for the body to manufacture the important brain neurotransmitter acetylcholine. Phosphatidylcholine helps to promote healthy cognitive function.