BRIEF REPORTS Exploring Developmental Differences in Visual Short-Term Memory and Working Memory Su Yin Ang and Kerry Lee Nanyang Technological University Although visuospatial short-term memory tasks have been found to engage more executive resources than do their phonological counterparts, it remains unclear whether this is due to intrinsic differences between the tasks or differences in participants’ experience with them. The authors found 11-year-olds’ performances on both visual short-term and working memory tasks to be more greatly impaired by an executive suppression task (random number generation) than were those of 8-year-olds. Similar findings with adults (e.g., Kane & Engle, 2000) suggest that the imposition of a suppression task may have overloaded the older children’s executive resources, which would otherwise be used for deploying strategies for performing the primary tasks. Conversely, the younger children, who probably never had the capacity or know-how to engage these facilitative strategies in the first place, performed more poorly in the single task condition but were less affected in the dual task condition. These findings suggest that differences in the children’s ability to deploy task-relevant strategy are likely to account for at least part of the executive resource requirements of visual memory tasks. Keywords: visuospatial working memory, executive functions, developmental differences, dual task interference, cognitive and mnemonic strategies According to Baddeley and Hitch (1974), working memory is a system that provides temporary storage and simultaneous process- ing or manipulation of information. It has been shown to predict higher cognitive functions or intellectual abilities, such as mathe- matical skills (Bull & Scerif, 2001; Lee, Ng, & Ng, 2009; Lee, Ng, Ng, & Lim, 2004; Logie, Gilhooly, & Wynn, 1994), reading skills (Hitch, Towse, & Hutton, 2001), and intelligence (Engle, Tuhol- ski, Laughlin, & Conway, 1999). Much of the earlier research focused on adults and the verbal component of the model. More recently, there has been interest in the visuospatial component (e.g., Pickering, 2001b; Logie, 1995) and the developmental rele- vance of the model (e.g., Baddeley & Hitch, 2000). The Visuospatial Sketchpad Although there is general agreement that the visuospatial sketchpad is not a unitary system, there are differing views on the properties of the subcomponents (Logie, 1995; Rudkin, Pearson, & Logie, 2007). Logie (1995) proposed that the visuospatial compo- nent consists of a visual cache, which passively stores visual information, and an inner scribe, which actively rehearses spatial and sequential movement as well as visual information. Other researchers have proposed a static and dynamic separation (Pick- ering, 2001a; Pickering, Gathercole, Hall, & Lloyd, 2001). The distinction between the visual/static versus spatial/dynamic com- ponents is best characterized by the Visual Patterns Test and the Corsi blocks task. The Visual Patterns Test (Della Sala, Gray, Baddeley, & Wilson, 1997) involves the presentation and recall of static or simultaneously presented matrices. In contrast, the Corsi blocks task (Milner, 1971) involves the recall of movement se- quences formed when an experimenter taps on a subset of blocks that have been randomly arranged among other blocks. In support of the visual/spatial divide, Della Sala, Gray, Baddeley, Allamano, and Wilson (1999) found that a visual interference task caused a decrease in performance on the Visual Patterns Test but not on the Corsi blocks task. Spatial tapping had the opposite effect. The Present Study Most previous research (e.g., Ang & Lee, 2008; Fisk & Sharp, 2003; Klauer & Stegmaier, 1997; Vandierendonck, Kemps, Fas- Su Yin Ang, Centre for Research in Pedagogy and Practice, National Institute of Education, Nanyang Technological University, Singapore; Kerry Lee, Centre for Research in Pedagogy and Practice and Psycholog- ical Studies Academic Group, National Institute of Education, Nanyang Technological University. This paper was presented as a poster session at the 20th biennial meeting of the International Society for the Study of Behavioural Development, Wu ¨rzburg, Germany, July 2008. This research was supported in part by grants from the Education Research Fund (EP 2/02 KL) and the Centre for Research in Pedagogy and Practice, National Institute of Education, Sin- gapore (CRP 9/05KL), awarded to Kerry Lee and by a scholarship from the Singapore Millennium Foundation awarded to Su Yin Ang. We thank all the children who participated in this study. We thank the teachers and principals for their assistance and for giving us access to their schools and all research assistants for their help in data collection. Correspondence concerning this article should be addressed to Su Yin Ang or Kerry Lee, Centre for Research in Pedagogy and Practice, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore 637616, Singapore. E-mail: SuYin.Ang@nie.edu.sg or Kerry.Lee@nie.edu.sg Developmental Psychology © 2010 American Psychological Association 2010, Vol. 46, No. 1, 279 –285 0012-1649/10/$12.00 DOI: 10.1037/a0017554 279