Two independent sources of difficulty in perspective-taking/theory of mind tasks.

Many perspective-taking and theory of mind tasks require participants to pass over the answer that is optimal from the self-perspective. For instance, in the classic change-of-location (false belief) task, participants are required to ignore where they know the object to be, and in the director task participants are required to ignore the best match for the instruction the other, less knowledgeable agent gives them (e.g., 'the top cup'). However, a second but equally critical requirement in such tasks is the ability to select a response which is wrong from the self-perspective; where the object is not, or an object that does not match the instruction (e.g., the middle cup instead of the top cup from one's own perspective). We present the results of an experiment that teases apart these two effects and demonstrate that both contribute independently to the difficulty in taking other perspectives. Reanalyses of data from previous experiments confirm this dual effect. These results suggest a revision of our understanding of egocentricity and difficulty in perspective-taking generally.