Phosphatidylcholine (PC) is a class of phospholipids which incorporates choline as a headgroup.

Because PC contains choline, it is essential for producing the neurotransmitter acetylcholine which is responsible for memory, motor function, and the function of your autonomic nervous system (ANS) that regulates "automatic" unconscious functions including breathing, heart rate, digestion and the function of all of your organs.

PS helps generate new brain cells, as well as maintain attention, memory and mood. It also reduces the stress hormone cortisol. 

Phosphatidylcholine (PC) can be isolated from either egg yolk or soy beans (either by mechanical extraction or chemical extraction using hexane).

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