Newborn Infants' Visual Responses to Square Wave Gratings

Abstract

vironment. Using the visual preference method, with paired stimulus presentation, 3 major conclusions result from the 4 experiments: (1) When the subjects are shown horizontal stripes, checkerboard patterns, and vertical stripes, with the stimuli equated for the amount of contour they contain, a strong ordering of preference is found such that H > Ch > V; (2) newborns will prefer horizontal to vertical square wave gratings over a range of spatial frequencies; (3) when presented with gratings of the same orientation, a preference for an intermediate range of spatial frequencies is found. It seems likely that these findings are determined by the activation of cells that respond optimally to a fairly narrow range of spatial frequencies, and by an orienting response associated with eye movement tendencies; these 2 effects act additively in determining the preferences found. The results show further that newborn babies are able to select among visual stimuli with great consistency. The implications of the present findings for developing visual function are discussed.