Do infants understand false beliefs? We don’t know yet – A commentary on Baillargeon, Buttelmann and Southgate’s commentary

Fourteen- to Eighteen-Month-Old Infants Use Explicit Linguistic Information to Update an Agent's False Belief

The current research examined how infants exploit linguistic information to update an agent's false belief about an object's location. Fourteen- to eighteen-month-old infants first watched a series of events involving two agents, a ball, and two containers (a box and a cup). Agent1 repeatedly acted on the ball and then put it in the box in the presence of agent2. Then agent1 disappeared from the scene and agent2 switched the ball's location from the box to the cup. Upon agent1's return, agent2 told her, "The ball is in the cup!" Agent1 then reached for either the cup (cup event) or the box (box event). The infants looked reliably longer if shown the box event as opposed to the cup event. However, when agent2 simply said, "The ball and the cup!" - which does not explicitly mention the ball's new location - infants looked significantly longer if shown the cup event as opposed the box event. These findings thus provide new evidence for false-belief understanding in infancy and suggest that infants expect an agent's false belief to be updated only by explicit verbal information.

Developmental progression of mental state understandings in infancy

This study establishes a sequence of developing mental state understandings in infants. We used three violation-of-expectation paradigms to assess fifty-seven 16-month-olds’ ability to (a) infer an actress’s intention from her prior repeated approaches to an object, (b) recognize her emotion by watching her facial-emotional display, and (c) deduce her false belief by noticing her lack of visual access to a change in the experimental setup. Contingencies between passing the three tasks were analyzed. Results showed that the infants made sense of intention first, followed by emotion, and then false belief. This progressive sequence parallels what has been found with preschoolers using verbal theory-of-mind tasks.