Clothing a model of embodiment

By delineating the parametric variations that affect infant performance in the standard A-not-B search task, the Thelen et al. model provides an impor tant contribution to the field of infant development. We discuss several br oad issues pertinent to interpreting the model. We note that the phenomenon modeled by Thelen et al. is not necessarily the one originally described b y Piaget. We describe data on infant self-correction that are riot addresse d by the Thelen et al. model. Finally, we suggest that psychological constr ucts such as representation and knowledge structures are valuable to our un derstanding of the A-not-B phenomenon in particular and psychological devel opment in general.