Phosphatidylserine (PS) is a critical component of cell membranes and is found in high concentrations in the brain, primarily in the cell membranes of neurons.* PS promotes brain function by helping maintain cell to cell communication which is essential for mental performance and attentiveness.* Bioclinic Naturals uses Sharp-PS Green Phosphatidylserine, which is derived from non-GMO sunflower oil and is 100% soy free.