The proposed studies are directed at describing taste sensitivity in the human infant by using the ingestive response as an index of efficacy of chemical stimuli. Studies are described which seek answers to the following questions: 1) Do human neonates respond differentially to the taste quality and intensity of chemical stimuli described by adults as sweet, sour, salty and bitter? 2) Does the taste sensitivity of the neonate change with age? 3) Is taste and acceptance of nutrients altered by hunger? 4) Is the infant able to discriminate among the taste quanities of nutrients?