This invention relates to the use of a nutritional composition comprising sialylated oligosaccharides for enhancing cognitive development and learning skills in mammals. The nutritional composition comprises 3′-Siallylactose (3′-SL) and 6′-Siallylactose (6′-SL) in a weight ratio between 10:1 and 1:10 and is specifically for use in enhancing learning skills and/or enhancing memory function in an individual by increasing the sialic acid (Neu5Ac) concentration in the brain of said individual.