The proposed interaction between working memory and inhibition

Abstract

Two experiments investigated the determinants of performance on a go/no-go task by studying the interplay of two executive function components, working memory (WM) and inhibition. Systematically varied task demands on WM and inhibition were used in the analysis of performance together with individual capacity measures of both functions, thereby investigating an interactive view of WM and inhibition. Further analyses were conducted with individual differences in general fluid intelligence (gF), in an attempt to study the role of higher order cognition in handling task demands. The results are new in presenting empirical evidence for interactive effects of the task demand variables in concert with individual WM capacity as well as with gF, suggesting that executive processes common to WM and gF are involved in inhibitory performance, whereas gF appears to reflect a broader function in controlling behaviour in relation to task goals, whether it involves active responding or not.

Acknowledgements

This research was supported by a grant to Gunilla Bohlin from The Swedish Research Council.

Notes

¹It should be noted that, for the measure of inhibition, low values indicate good inhibitory capacity.

²The majority of the individual difference variables met the standard criteria for univariate normality (Kline, 1998) with skewness less than 3 and kurtosis less than 4. The gF measure showed significant kurtosis, and squared root transformations were therefore used, resulting in normalised distributions. Analyses with the transformed variable did not change the overall conclusions.

³Again, note that, for the measure of inhibition, low values indicate good inhibitory capacity.

⁴The measure of inhibitory capacity showed significant kurtosis, and squared root transformations were therefore used, resulting in normalised distributions. Analyses with the transformed variable did not change the overall conclusions.