Inhibitory control and children's mathematical ability

Abstract

Following recent research linking executive functioning to children 's skills, this thesis explores the relationship between children's inhibition effciency and mathematical ability. This relationship was initially explored using six Stroop task variants containing verbal, numerical or pictorial stimuli. The results indicated that, in the numerical variants only, children of lower mathematical abilty possess less effcient inhibition mechanisms, compared to children of higher mathematical ability. Thus, it is proposed that low-abilty mathematicians may possess a domain-specifc problem with the inhibition of numerical information. The increased interference scores of the lowability mathematicians, however, were only evident under those conditions which also required a degree of switching between temporary strategies. A series of experiments also examined children's ability to inhibit prepotent responses and switch between strategies whilst performing mental arithmetic. The aim of these experiments was to provide a more naturalistic and appropriate exploration of the hypothesized relationship between mathematical abilty and inhibition effciency. These results also indicated that low-ability mathematicians possess fewer executive resources to cope with increased inhibition demands. A further systematic manipulation of switching and inhibition demands revealed that the low-abilty mathematicians experienced a particular difculty when both types of inhibitory demands (i.e. inhibiting a prepotent response and inhibiting an established strategy)were present. This suggests that their reduction in inhibition effciency stems from the amount of demands, rather than the type of demands placed on the executive system. Furthermore, the results indicated that inhibition effciency may be a specifc element of mathematical ability rather than an element of intellectual ability in general. The final study involved a group of low-abilty mathematicians and examined the disturbing impact of irrelevant information on their arithmetic word problem solving abilty. This study revealed that irrelevant numerical (IN) information has a more detrimental impact on performance than irrelevant verbal (IV) information. It is proposed that it is more difcult to inhibit IN information, as it appears more relevant to intentions, and thus, enters WM with a higher level of activations. In sum, the results indicate that low-abilty mathematicians have a reduced domainspecific working memory capacity, characterized by ineffcient inhibition mechanisms.