Heuristic and analytic processing: Age trends and associations with cognitive ability and cognitive styles Judite V. Kokis, a Robyn Macpherson, a Maggie E. Toplak, b Richard F. West, c and Keith E. Stanovich a, * a University of Toronto, Ont., Canada M5S 1V6 b Brain and Behaviour Research Program, The Hospital for Sick Children, Ont., Canada M5G 1X8 c James Madison University, Harrisonburg, Virginia, 22807, USA Received 5 February 2002; revised 23 July 2002 Abstract Developmental and individual differences in the tendency to favor analytic re- sponses over heuristic responses were examined in children of two different ages (10- and 11-year-olds versus 13-year-olds), and of widely varying cognitive ability. Three tasks were examined that all required analytic processing to override heuristic processing: inductive reasoning, deductive reasoning under conditions of belief bias, and probabilistic reasoning. Significant increases in analytic responding with devel- opment were observed on the first two tasks. Cognitive ability was associated with analytic responding on all three tasks. Cognitive style measures such as actively open-mindedthinkingandneedforcognitionexplainedvarianceinanalyticrespond- ing on the tasks after variance shared with cognitive ability had been controlled. The implications for dual-process theories of cognition and cognitive development are discussed. Ó 2002 Elsevier Science (USA). All rights reserved. J. Experimental Child Psychology 83 (2002) 26–52 www.academicpress.com * Corresponding author. E-mail address: Kstanovich@oise.utoronto.ca (K.E. Stanovich). 0022-0965/02/$ - see front matter Ó 2002 Elsevier Science (USA). All rights reserved. PII:S0022-0965(02)00121-2