Neonatal Stepping in Relation to Terrestrial Optic Flow


  • We would like to thank F. Jouen and M. Bui for their help in designing the visual stimuli, L. Vaivre-Douret for advice on the stepping procedure, M. Trujillo for advice on coding the stepping, and all the mothers and infants for their participation. This work was supported by the Centre National de la Recherche Scientifique, the France-Berkeley Fund, National Institute of Child Health and Human Development Grant grant HD050638, and Grant P20MD00262 from the National Center on Minority Health and Health Disparities.

concerning this article should be addressed to Marianne Barbu-Roth, Laboratoire Psychologie de la Perception, UMR 8158 CNRS, Université Paris Descartes, UFR Biomédicale, 45 rue des Saints Péres, 75006 Paris, France. Electronic mail may be sent to


This experiment examined whether newborn stepping, a primitive form of bipedal locomotion, could be modulated by optical flow. Forty-eight 3-day-old infants were exposed to optical flows that were projected onto a horizontal surface above which the infants were suspended. Significantly more air steps were elicited by exposure to a terrestrial optical flow specifying forward translation than by a rotating optical flow or a static optical pattern. Thus, a rudimentary coupling between optical flow and stepping is present at birth, suggesting a precocious capacity in the newborn to perceive and utilize visual information specifying self-motion. The findings may help the early diagnosis of infants with visual or visual-motor deficits and the development of visually based interventions for disabled infants.