The Effect Of Shifting/Updating Executive Function On Mathematics Learning Disabilities Children’s Strategy Use In Computational Estimation

Numerous studies had found that individuals were able to use a variety ofstrategies to solve arithmetic cognitive tasks (Lemaire, Lecacheur，&Farioli,2000).Individual’s ability of strategy use played an important role in problem-solving, whichwas a sign of cognitive flexibility. Given the mathematical ability is closely related toour daily life and the incidence of mathematical learning difficulties is high,researchers begin to put more and more attention on children’s characteristic on theperformance of strategic use and possible causes who have mathematics learningdifficulties. ZHU (1999) found that the strategies that were used by children withmathematics difficulties were more common and lower levels (longer reaction timeand higher error rates) than those of normal achievement children. Recentlyresearchers began to notice that the central executive function of working memoryhad an important impact on the performance of children’s arithmetic cognitivestrategies, which found that the impact of the central executive function was reflectednot only in the arithmetic processing performance (Seitz&Schumann-Hengsteler,2000; Imbo, Vandierendonck，&Rammelaere,2007), but also in arithmetic strategyuse (Wang&Chen,2006; Lemaire&Lecacheur,2010). With the increasing focus ofseparability of the central executive function, the researchers found that thesub-components of the central executive function (inhibition, updating and shifting)played an important role in the individual’s strategies use (Hodzik&Lemaire,2011;Wang,2011, etc.). Studies had found that arithmetic skills played an impact onindividual’s strategy use (Thevenot, Fanget,&Fayol,2007, etc.). So we tookarithmetic skills as a covariate variable. Based on the above findings, the presentstudy explored shifting and updating functions how to affect strategy use incomputational estimation of children with mathematical learning difficulties,and inorder to explore the strategy use of mathematical learning difficulties children isdelayed or defect, we selected fifth-grade normal achievement children whoseintelligence matched with children with mathematical learning difficulties.The first experiment adopted the method of combination between choice/ no-choice and tasks shifting paradigm (including baseline measurement and shiftingmeasurement, baseline measurements were computational estimation of two two-digitnumbers while shifting measurements were shifting between computationalestimation of two two-digit numbers and comparison of two two-digit numbers),21sixth-grade children with mathematics learning disabilities (MD),20normallyachieving (NA) children in the sixth grade and20fifth-grade normallyintelligence-match achieving (MA) children were chosen to be tested. The secondexperimental adopted method of combination between choice/no-choice and runningmemory paradigm (including baseline measurement and updating measurement,baseline measurements were computational estimation of two two-digit numberswhich appeared after pressing the backspace button while updating measurementswere computational estimation of the last two two-digit numbers which appears afterpressing the backspace button, no matter appears2or3or4two-digit numbers),20sixth-grade MD children,24NA children in the sixth grade and19fifth-grade MAchildren were chosen to be tested.The results showed that:(1) Shifting and updating process didn’t show any impact on individual’s strategydistribution or on that of children with mathematical learning disabilities.(2) Both shifting and updating had significant impact on individual’s strategyexecution. Shifting had a significant effect on the rounding-down strategies executionof the all groups；but on rounding-up strategy execution，shifting only affectedchildren with mathematical learning disabilities. Compared with normal groups,strategy execution of children with mathematical learning disabilities were moreaffected by updating process.(3) Both shifting and updating had significant impact on individual’s strategyselection. Updating affected all the participants’ strategy selection in three groups, butthe fifth grader group was more easily affected by updating.(4) Shifting didn’t show any impact on strategy selection adaptivity of anindividual or on that of children with mathematical learning disabilities. However,individual’s strategy selection adaptivity was affected by updating.(5) The Experiment1showed that strategy use of children with mathematicallearning disabilities were developmental delay; while the Experiment2found thatstrategy selection of children with mathematical learning disabilities was developmental delay, but their performance on strategy execution and strategyselection adaptivity were not as well as their intelligence-matched group.