"PhosphatidylSerine (PS) is a nutrient building block for cell membranes. All cells use membranes to make and convert energy, and carry out life processes. As they age, healthy individuals can lose as much as half of their ability to perform everyday tasks related to memory and cognition. PhosphatidylSerine is a nutrient found most concentrated in brain cells. Extensive clinical studies indicate that PS supplementation can help slow down the mental decline associated with aging. "