Differential Development of Object and Location Processing is a Critical Factor to a Child's Passing or Failing Explicit False-Belief Tasks.

It is well-documented that 5-year-olds consistently pass explicit false-belief tasks-one of the most common tests for assessing "Theory of Mind" (ToM). But what about younger children? While some studies find that 3- and 4-year-olds fail explicit false-belief tasks, other studies find that these same age children pass such tasks, leading to confusion about exactly when, and why, children pass false-belief tasks. Traditionally, explicit false-belief tasks include scenarios with object changes (e.g., Smarties task) or location changes (e.g., Sally-Anne task). However, object and location information are prioritized differentially throughout development, with preschoolers weighting cues about objects over locations. Thus, here we ask whether a child younger than 5 years old could pass an explicit false-belief task about objects yet fail one about locations, hypothesizing that the development of information processing is a critical factor that contributes to false-belief performance. To directly test this hypothesis, 3- to 5-year-olds participated in a novel explicit false-belief task with independent object- and location-change trials. Consistent with our hypothesis, we found i) that all participants performed significantly better on object than location trials, and ii) a significant number of 3- and 4-year-olds who passed the object trials yet failed the location trials. These findings demonstrate that when testing the development of false belief (or potentially any other cognitive abilities using object and location information), one must consider developmental differences in information processing, since such differences can yield opposite answers and, crucially, opposite conclusions.