Why Do Children From Age 4 Fail True Belief Tasks? A Decision Experiment Testing Competence Versus Performance Limitation Accounts.

The standard view on Theory of Mind (ToM) is that the mastery of the false belief (FB) task around age 4 marks the ontogenetic emergence of full-fledged meta-representational ToM. Recently, a puzzling finding has emerged: Once children master the FB task, they begin to fail true belief (TB) control tasks. This finding threatens the validity of FB tasks and the standard view.  Here, we test two prominent attempts to explain the puzzling findings against each other. The perceptual access reasoning account (a competence limitation account) assumes that children at age 4 do not yet engage in meta-representation, but use simpler heuristics ("if an agent has perceptual access, she knows and then acts successfully; otherwise, she acts unsuccessfully"). In contrast, the pragmatics approach (a performance limitation account) suggests that children at age 4 do have meta-representational ToM but are confused by pragmatic task factors of the TB task. The current study tested competing predictions of both accounts in a decision experiment. Results from 165 4- to 7-year-olds reveal that failure in the TB task disappeared once the tasks were modified: children mastered both FB and TB tasks when the latter were adapted in terms of heuristic and pragmatic factors. Importantly, this pattern held in conditions in which the pragmatics account predicts success, but the perceptual access account predicts failure. Overall, the present findings thus corroborate the standard view (children use meta-representational ToM from age 4, at the latest) and suggest that difficulties with TB tasks merely reflect pragmatic performance factors.