[7] In the plasma membrane, PS is localized exclusively in the cytoplasmic leaflet where it forms part of protein docking sites necessary for the activation of several key signaling pathways.

These include the Akt, protein kinase C (PKC) and Raf-1 signaling that is known to stimulate neuronal survival, neurite growth, and synaptogenesis.

Phosphatidylserine is formed in bacteria (such as E. coli) through a displacement of cytidine monophosphate (CMP) through a nucleophilic attack by the hydroxyl functional group of serine.

Only small amounts are found in dairy products and vegetables, with the exception of white beans and soy lecithin.

"[20][21][citation needed][failed verification] According to the FDA, there is a lack of scientific agreement amongst qualified experts that a relationship exists between phosphatidylserine and cognitive function.

[20] More recent reviews have suggested that the relationship may be more robust,[22][better source needed][23][failed verification] though the mechanism remains unclear.

[25][failed verification][better source needed] Some studies have suggested that whether the phosphatidylserine is plant- or animal-derived may have significance, with the FDA's statement applying specifically to soy-derived products.

[26] A 2002 safety report determined supplementation in elderly people at a dosage of 200 mg three times daily to be safe.