Central Executive Load On Age-related Differences In Strategy Use

With the proposal of the cognitive flexibility, cognitive science researchers not only concernabout individual strategy utilization, but also pay attention to the adaptability of strategy choice.Siegler and Lemaire proposed a general conceptual framework to describe the utility of individualcognitive strategies as well as explained how to use different strategies by individuals. Theframework includes strategy repertoire, strategy distribution, strategy execution and strategyselection. Although there have been many strategy choice models to explain how to use thearithmetic cognitive strategy, the role the central executive load playing in the strategy utilizationis still far from clear, since few strategy choice models referring to the strategy selection in moredifficult situation have been established. Computational estimation is one of the hot research fieldsof arithmetic cognition. The individual strategy utilization is affected by multiple individualdifference factors, such us central executive load and arithmetic skills. To date, research findingsgaining from CRT task study remain inconsistent, therefore, some suggestes that the CRT task notoccupy the central executive resources. According to Logie, Gilhooly and Wynn (1994), it hasbeen demonstrated that different sub-tasks affected the mental arithmetic. More recent studies alsorevealed that inhibition and shifting capacities mediated age-related differences in strategyselection (Lemaire, & Lecacheur, 2011; Hodzik, & Lemaire, 2011). Dual-task paradigm iscommonly utilized in exploring working memory load in arithmetic performance, and thechoice/no-choice is a standard method to obtain unbiased data about the strategy utilization. Fromthe above, in this study we intend to control the arithmetic skills as well as employ the dual-taskparadigm and choice/no-choice method to investigate the influence central executive load havingupon individual strategies utilization, and further to explore the age-related differences in strategyutilization.130 fourth grader students, 125 sixth grade students and 138 adults were selected accordingto cluster sampling method. First, the subjects needed to complete the the French Kit. Then, they were asked to finish a two-digit addition computational estimate and complete the secondary taskat the same time. The experiment design was as following: 5(consistent–high load,consistent–low load, inconsistent–high load, inconsistent–low load, no load)×3(best-strategychoice condition, no-choice/rounding-up condition, no-choice/rounding-down condition)×3(fourth grader, sixth grade, adults). The main task was to finish 30 two-digit addition questions,and the secondary task employed the Sang-Hoon Han and Min-Shik, Kim’s (2004) design withsome modification.The main conclusions are as follows:(1) The performances of strategy utilization were affected not only by age but also bydifferent strategies, where the most pronounced progresses were observed in low-grade studentsmastering the simpler strategy.(2) It showed that strategy execution was also impacted by age-dependent load. Specifically,the influence of central executive load on children was great in low-grade while few inhigh-grade; adults distinguishing the differences between the central executive load typesperformed the speed - accuracy trade-off.(3) The central executive load had a greater effect on strategy selection than on strategyexecution. The central executive load, as long as it existed, affected the performance of strategicselection, which suggested that the strategy selection require more central executive function.(4) Adaptivity of strategy choices improved with the increase in age. Whereas in the centralexecutive load situation, the adaptive performance was worse as individual could not choose thebest strategy based on the question. Therefore, conclusions can be drawn that central executiveload affected the adaptivity of strategy choices.(5) The advantages of rounding-down strategy outweighed. In comparison with rounding-upstrategy, rounding-down strategy was more effective, less time-consuming and need fewerresources. Furthermore, the impact of central executive load on rounding-down strategy was less.Additionally, no significant differences of the impaction on addition estimates was observedbetween consistent tasks and inconsistent task.