PAPER Three-year-olds express suspense when an agent approaches a scene with a false belief Henrike Moll, Sarah Kane and Luke McGowan Department of Psychology, University of Southern California, Los Angeles, USA Abstract Research on early false belief understanding has entirely relied on affect-neutral measures such as judgments (standard tasks), attentional allocation (looking duration, preferential looking, anticipatory looking), or active intervention. We used a novel, affective measure to test whether preschoolers affectively anticipate another’s misguided acts. In two experiments, 3-year-olds showed more expressions of suspense (by, e.g. brow furrowing or lip biting) when they saw an agent approach a scene with a false as opposed to a true belief (Experiment 1) or ignorance (Experiment 2). This shows that the children anticipated the agent’s surprise and disappointment when encountering reality. The findings suggest that early implicit knowledge of false beliefs includes anticipations of the affective implications of erring. This vital dimension of beliefs should no longer be ignored in research on early theory of mind. Research highlights • Three-year-olds’ expressions of suspense were recorded while they were watching puppet shows involving false beliefs. • Participants expressed more suspense in anticipation of an agent approaching reality with a false as opposed to a true belief or ignorance. • Results indicate that early false belief understanding includes an awareness of the affective consequences of being wrong. Introduction As social agents, humans have to be aware of how others represent the world, whether these representations are accurate or not. This allows them to anticipate, correct, explain, and justify actions that are objectively mis- guided but make sense from the agent’s epistemic viewpoint. Classic tests have uniformly shown that children younger than 4 to 5 cannot identify false assumptions in themselves or others (Wellman, Cross & Watson, 2001). Three-year-olds of various cultures (Liu, Wellman, Tardif& Sabbagh, 2008) confidently state that a misinformed agent acts on and represents the world as it is (Ruffman, Garnham, Import & Conolly, 2001; Wimmer & Perner, 1983). In the last couple of decades, new research techniques have emerged that dispense with the question–answer format of the classic tests and reveal a much earlier, implicit grasp of beliefs. These tests fall into three basic categories: One in which young children are observers (looking time, preferential looking, and anticipatory looking studies), a second in which they directly interact with the misinformed agent (interactive studies), and a third in which they adopt the role as narrators (narrative studies). The first category has revealed that even infants are perceptually sensitive to belief manipulations: Seven- month-olds gaze longer at a scene that is unexpected for another agent (Kov acs, T egl as & Endress, 2010) and by 1 year, they look longer when an agent acts in away that is inconsistent with her prior observations (Onishi & Baillargeon, 2005; Surian, Caldi & Sperber, 2007; Surian & Geraci, 2012). By 2.5 years, children visually anticipate where a misinformed agent will look for her object Address for correspondence: Henrike Moll, Department of Psychology, University of Southern California, 3620 South McClintock Avenue, Los Angeles, CA 90089-1061, USA; e-mail: hmoll@usc.edu © 2015 John Wiley & Sons Ltd Developmental Science (2015), pp 1–13 DOI: 10.1111/desc.12310