In recent years, the impact of domain-general cognitive abilities on numerical cognition has gained increasing research interest (e.g., Cowan & Powell,
2014; Geary,
2011; Hohol, Cipora, Willmes, & Nuerk,
2017; Passolunghi and Lanfranchi,
2012; Peng, Namkung, Barnes, & Sun,
2016). One focus was on the influence of cognitive control designating the ability of the human cognitive system “to configure itself for the performance of specific tasks through appropriate adjustments in perceptual selection, response biasing, and the on-line maintenance of contextual information (Botvinick, Braver, Barch, Carter, & Cohen,
2001, p. 624)”. However, so far an influence of cognitive control on numerical cognition was primarily investigated when evaluating rather passive adaptation to stimulus set characteristics (Huber et al.,
2013; Huber, Moeller, & Nuerk,
2014; Macizo & Herrera,
2011; Moeller, Klein, & Nuerk,
2013) or order (Macizo & Herrera,
2013; Pfister, Schroeder, & Kunde,
2013). Evidence for an influence of more active instantiations of cognitive control on numerical cognition is still scarce. By active we refer to situations, in which participants have to actively exert cognitive control to coordinate actions for the task at hand as, for instance, required in task switching paradigms. This seems all the more relevant, because numbers are commonly used stimuli in task-switching paradigms (e.g., Koch & Allport,
2006; Sudevan & Taylor,
1987), and there is first evidence in the literature that task switching may influence the processing of numerical information (Wendt, Kiesel, Mathew, Luna-Rodriguez, & Jacobsen,
2013). Accordingly, this study employed a task switching paradigm requiring participants to actively coordinate their response actions instead of passively adapting to stimuli characteristics. We evaluated whether cognitive control demands (i.e., switches between input–output modality couples) influenced basic number magnitude processing as reflected by the numerical distance effect and the problem size effect. Such alterations of number magnitude processing would provide further evidence that numerical cognition is under cognitive control.
In the following, we will first review recent findings regarding influences of cognitive control on numerical cognition. We then introduce the key notions of task switching, input–output modality compatibility and the respective numerical effects to be investigated in the current study before describing its details.