title: The Invisible Hand: Toddlers Connect Probabilistic Events With Agentive Causes.
abstract: Children posit unobserved causes when events appear to occur spontaneously (e.g., Gelman & Gottfried, 1996). What about when events appear to occur probabilistically? Here toddlers (M = 20.1 months) saw arbitrary causal relationships (Cause A generated Effect A; Cause B generated Effect B) in a fixed, alternating order. The relationships were then changed in one of two ways. In the Deterministic condition, the event order changed (Event B preceded Event A); in the Probabilistic condition, the causal relationships changed (Cause A generated Effect B; Cause B generated Effect A). As intended, toddlers looked equally long at both changes (Experiment 1). We then introduced a previously unseen candidate cause. Toddlers looked longer at the appearance of a hand (Experiment 2) and novel agent (Experiment 3) in the Deterministic than the Probabilistic conditions, but looked equally long at novel non-agents (Experiment 4), suggesting that by 2 years of age, toddlers connect probabilistic events with unobserved agents.
authors.affiliation: Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology.
authors.forename: Yang
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Department of Psychology, Tufts University.
authors.forename: Paul
authors.initials: P
authors.lastname: Muentener
authors.affiliation: Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology.
authors.forename: Laura E
authors.initials: LE
authors.lastname: Schulz
mesh_terms: D002675:Child, Preschool; D003071:Cognition / Q000502:physiology*; D003210:Concept Formation / Q000502:physiology*; D005260:Female; D006801:Humans; D007223:Infant; D007600:Judgment / Q000502:physiology*; D007858:Learning / Q000502:physiology*; D008297:Male; D011340:Problem Solving / Q000502:physiology*
keywords: Agency; Causal learning; Determinism; Toddlers; Unobserved causes