The nativism and the constructivism are two extreme views in the theories of development. The nativism claims that the long history of evolution of human beings provides a newborn infant an innate competence to adapt to the environment, while the constructivism argues that an infant is an incomplete system which must be incrementally developed by interactions with the complex environment. To resolve the controversy between these views, I will focus on dynamic properties of motion and perception that young infants exhibit; U-shaped appearance, disappearance, and reappearance of behavior. In this symposium, I will present studies on (1) motion analysis of spontaneous movements of young infants, (2) visual perception of young infants using the method of infant control habituation, and (3) brain imaging of infants using the optical topography.
