ELSEVIER Neuropsychologia 44 (2006) 2037-2078 IWUROPSYCHOLOGIA www elsevier comilocateineumpsychologia Development of cognitive control and executive functions from 4 to 13 years: Evidence from manipulations of memory, inhibition, and task switching Matthew C. Davidson a'b, Dima Amso a, Loren Cruess Anderson c, Adele Diamond d,* Sackler Institute for Developmental Psychobiologx frill Medical College of Cornell University; New York. NY. USA b Department of Psychologx University of Massachusetts. Amherst. MA. USA Shrive, Center. University of Massachusetts Medical School, Waltham. MA. USA d Department of Psychiatrx University of British Columbia & Division of Child & Adolescent Psychiatty, BC Children's Hospital. Vancouver. Canada Received 20 November 2005: received in revised form 7 February 2006: accepted 10 February 2006 Available online 31 March 2006 Abstract Predictions concerning development, interrelations, and possible independence of working memory, inhibition, and cognitive flexibility were tested in 325 panicipants (roughly 30 per age from 4 to 13 years and young adults.. 50% female). All were tested on the same computerized battery. designed to manipulate memory and inhibition independently and together. in steady state (single-task blocks) and during task-switching. and to be appropriate over the lifespan and for neuroimaging (MARI). This is one of the first studies, in children or adults, to explore: (a) how memory requirements interact with spatial compatibility and (b) spatial incompatibility effects both with stimulus-specific rules (Simon task) and with higher-level, conceptual rules. Even the youngest children could hold information in mind, inhibit a dominant response. and combine those as long as the inhibition required was steady-state and the rules remained constant. Cognitive flexibility (switching between rules), even with memory demands minimized, showed a longer developmental progression. with 13-year-olds still not at ad