Phosphatidylserine (PS) is a natural nutrient found in the brain. Phosphatidylserine is the major phospholipid in the brain where it plays a major role in determining the integrity and fluidity of cell membranes. Healthy cell membranes support healthy brain functions such as memory, focus and clarity. In clinical studies, plant-based PS is just as effective as animal-based PS with none of the concerns associated with prion diseases (i.e. Mad Cow disease). Clinical studies on humans verify PS safety.