Testing “quarantined” metarepresentational accounts of Theory of Mind: Are we biased by others' false beliefs?

An important component of Theory of Mind is the ability to understand the beliefs (true or false) of others. Arguably the most widely-held view is that this is performed by a detached belief-representation process (e.g., metarepresenting that another agent has a belief about the world which one does not share). The standard belief-representation account posits a separation between one's own first-order representations of the physical environment and one's second-order representations of another agent's mental states, preventing the latter from infecting the former. An alternative process is engaged belief-simulation (e.g., imaginatively adopting another agent's belief about the world) which, in contrast to standard belief-representation, posits a correspondence in the mental states shared by oneself and another agent and predicts an influence of the other agent's beliefs on one's own first-order representations and egocentric actions. In the first two of three studies, a participant and an agent watched an object buried in a continuous space (sandbox). The participant then watched the same object moved from the first location to a new location. When participants were asked to search for the object, they demonstrated a bias towards the first location when the agent falsely believed the object to be there but not when the agent knew, like the participant, that the object was in the new location. Reasoning that the strength of this bias may have been limited by participants' knowledge of the object's true whereabouts, in a third and final study we hid the movement of the object so that participants did not know its true location. We also recruited a greater number of participants to increase statistical power. Contrary to expectations, there was now no evidence of belief infection. Overall, these results are more consistent with a belief-representation account for (human) adults' understanding of others' belief states.