Differential Contributions of Set-Shifting and Monitoring to Dual-Task Interference

Abstract

It is commonly argued that complex behaviour is regulated by a number of "executive functions" which work to co-ordinate the operation of disparate cognitive systems in the service of an overall goal. However, the identity, roles, and interactions of specific putative executive functions remain contentious, even within widely accepted tests of executive function. The authors present two experiments that use dual-task interference to provide further support for multiple distinct executive functions and to establish the differential contributions of those functions in two relatively complex executive tasks -Random Generation and the Wisconsin Card Sorting Test. Results are interpreted in terms of process models of the complex executive tasks.

Set-shifting as a component process of goal-directed problem-solving

“…Moreover, during debriefing many subjects spontaneously reported that the go/no-go task was least effortful. Note though that when in another experiment the same auditory-vocal tasks were paired with a different primary task -random generation (Cooper et al, 2012) -it was the 2-back (memory) task and not the digit-switching (set-shifting) task that was performed most poorly and that led on several measures to greatest interference. Thus, the digit-switching task does not appear to be intrinsically more difficult than the 2-back task.…”

“…The procedure followed closely that used by Cooper et al (2012) in their study of dual-task interference, with the only difference relating to administration of the primary task (the Tower of London). Thus, the nature of the experiment was first described to participants.…”

“…Thus, participants who performed well on a range of simple response inhibition tasks tended to complete the target problems in fewer moves than participants who performed poorly on those tasks. A significant difficulty with this analysis is the statistical procedure used to support the conclusion (Cooper et al, 2012), which involves estimating latent factors corresponding to three executive functions and then comparing fits of structural equation models built upon these latent factors. Any error in estimating the latent factors will be compounded in the structural equation models, limiting the extent to which strong conclusions can be drawn from subtle differences in the fits of contrasting models.…”

“…However, in the Phillips et al study the secondary tasks were relatively complex. Random generation, for example, appears to draw upon multiple executive functions (Towse & Neil, 1998;Miyake et al, 2000;Cooper et al, 2012). And in the dual-task experiment of Cheetham et al (2012) the focus was on verbal versus visuospatial working memory rather than on executive functions more generally.…”

“…And in the dual-task experiment of Cheetham et al (2012) the focus was on verbal versus visuospatial working memory rather than on executive functions more generally. The approach of the present study, following Cooper et al (2012), focuses on the differential involvement of specific executive functions. We investigate the interference effects of relatively simple executive tasks on primary task performance.…”