Nine- to 11-month-old infants reasoning about causality in anomalous human movements

Abstract

Two habituation experiments investigated 9-11-month-old infants' reasoning about causality in anomalous human movements. During habituation, infants saw an event in which a person walked toward a stationary person behind an occluder who fell down after an interval. Then, the infants were tested with two events without the occluder: the contact event in which the first person pushed the second one to fall down and the no-contact event in which the second person fell down without any contact. In Experiment 1, in which the persons were face-to-back, infants looked at the no-contact event for a longer time, whereas in Experiment 2, in which the persons were face-to-face, they looked at both the events for equal duration. Thus, infants considered it unnatural when a person fell down without external force in the absence of any action from a distance (e.g. communication). Infants seem to apply the physical contact principles to human movements in certain cases. © Japanese Psychological Association 2009.