The role of phonological and executive working memory resources in simple arithmetic strategies

Abstract

The current study investigated the role of the central executive and the phonological loop in arithmetic strategies to solve simple addition problems (Experiment 1) and simple subtraction problems (Experiment 2). The choice/no-choice method was used to investigate strategy execution and strategy selection independently. The central executive was involved in both retrieval and procedural strategies, but played a larger role in the latter than in the former. Active phonological processes played a role in procedural strategies only. Passive phonological resources, finally, were only needed when counting was used to solve subtraction problems. No effects of working memory load on strategy selection were observed.

Acknowledgements

The research reported in this paper was supported by grant no. 011D07803 of the Special Research Fund at Ghent University to the first author and by grant no. 10251101 of the Special Research Fund of Ghent University to the second author. Thanks are extended to Koen Luwel, Jeff Bisanz, and two anonymous reviewers for their helpful comments on previous drafts of this paper.

Notes

¹More recently, a third slave system was proposed by Baddeley (2000), namely the episodic buffer. This system integrates information in both other slave systems with information from long-term memory.

²In both no-load and load session, choice conditions administered first in order to exclude influence of no-choice conditions on the choice condition. However, as there were two choice conditions (one in the no-load session and one in the load session), order effects still might have occurred. A paired-samples t-test indicated a small but significant difference between first-session (no-load or load) choice RTs and second-session (load or no-load) choice RTs, t(84) = 2.3, with RTs in the second session being 70 ms smaller than those in the first one. However, as working memory load was counterbalanced across participants, the bias resulting from this general speeding effect should be small to nonexistent.