For many years phospholipids have been studied mainly for their possible use as membrane models or cell-like carriers. Recently, on the basis of the new knowledge on the phospholipid membrane structure and function, a novel interest has arisen on the pharmacological properties of these compounds particularly at cerebral level. In this context particular attention has been devoted to phosphatidylserine (BC-PS), an anionic phospholipid extracted and purified from bovine brain, which in young animals has been shown to modify a number of brain electrophysiological and biochemical parameters.