Differential contribution of task conflicts to task switch cost and task mixing cost in alternating runs and cued task-switching: evidence from ex-Gaussian modeling of reaction time distributions

Abstract

Task switching involves switch cost (poorer performance switch trials than in task-repetition trials) and mixing cost (poorer performance in task-repetition trials than in trials from blocks without task switching). These are mainly studied with the alternating runs task-switching (ARTS) paradigm (in which the task changes every constant number of trials) or the cued task-switching (CTS) paradigm, in which the tasks change randomly. The authors tested the hypothesis that dealing with actual or potential conflicts regarding which task is currently required contribute to mixing cost in CTS more than in ARTS and contribute to switch costs more in ARTS than in CTS. This hypothesis was tested using ex-Gaussian modeling of reaction time (RT) distributions, in which the heaviness of the right tail marks task conflicts (Steinhauser and Hübner in J Exp Psychol Human Percept Perform 35:1398-1412 2009). As predicted, a heavier RT-distribution tail marked switch cost more strongly in ARTS than in CTS and marked mixing costs more strongly in CTS than in ARTS. These results indicate that switch cost and mixing cost reflect different processes in different task-switching paradigms.

Examining the Trainability and Transferability of Working-Memory Gating Policies

“…While such outcome can point to noise in our data, one cannot exclude the possibility that the absent Bayesian support for the alternative hypothesis is due to methodological limitation such as sample size or training dosage. Nonetheless, as argued by several authors, in the cued version of the task switching task, switch and repeat trials share preparatory processes (Dreisbach et al 2002;Meiran et al 2008;Shahar and Meiran 2014;Sohn and Anderson 2001).This is inherent in the unpredictable ordering of the task, requiring participants to know in advance the nature of the upcoming task (regardless if it repeats from the previous trial). These theories thus predict a benefit of CF training in both switch and repeat trials.…”

“…This is supported by line of research suggesting benefits of enhanced cue processing and preparation processes to task switching performance (e.g., Meiran 1996; Savine and Braver 2010; for review see Kiesel et al 2010). When assuming a switchspecific advanced preparation benefit, it is then expected that a higher reduction on switches when compared to repetitions will be observed, leading to a reduction in switch costs in the CF but not the CL condition (e.g., De Jong 2000; Rogers and Monsell 1995 but see Dreisbach et al 2002;Meiran et al 2008;Shahar and Meiran 2014;Sohn and Anderson 2001). 2.…”

Task Conflict and Task Control: A Mini-Review

“…Accordingly, the RT difference between non-word neutrals (which serve as a conflict-free baseline of general performance) and congruent conditions commonly serves as a measure of task conflict (Goldfarb and Henik, 2007; Kalanthroff et al., 2018a). Dissociation between the two conflicts was demonstrated by their diverse patterns of brain activation (Aarts et al., 2009; Desmet et al., 2011; Elchlepp et al., 2013) and their reflection in different components of an ex-Gaussian distribution (Steinhauser and Hübner, 2009; also see Aarts et al., 2009; Moutsopoulou and Waszak, 2012; Shahar and Meiran, 2015). These findings support the existence of task conflict as a specific type of conflict that is dissociated from other conflict types.…”

Monitoring and control in multitasking

“…Task conflict and response conflict can be further dissociated by analyzing RT distributions. When fitting an ex-Gaussian function, task versus response conflict are mainly reflected in the exponential versus the Gaussian compononent, respectively (Steinhauser & Hübner, 2009; see also Moutsopoulou & Waszak, 2012;Shahar & Meiran, 2015). Kalanthroff et al (2018) provided a formal computational model for the interaction of task conflict with response conflict in the Stroop task.…”