PS (phosphatidylserine) is a component found in large quantities in the brain, and is believed to play an important role in maintaining healthy cognitive function. PS can be found in trace amounts in soybeans, but it is very difficult to eat enough for it to be effective. Taking a supplement is therefore the most efficient way to obtain PS. Recommended for people who are concerned about their memory and cognitive function, people who are worried about forgetfulness, and people who feel unable to concentrate.