Control over task conflict in the stroop and affordances tasks: an individual differences study

Task conflict is a type of conflict that emerges when a stimulus triggers two or more competing tasks. In the Stroop task, task conflict occurs between the relevant color-naming task and irrelevant word reading task and can be observed mainly on congruent trials, which only involve task conflict and are devoid of additional conflict types. We hypothesized that task conflict also manifests in the affordances task between the relevant task (e.g., classifying manipulatable objects), and the automatic task afforded by the object (e.g., grasping the object), and is mostly evident on congruent trials. Using an individual differences design we assessed the relationship between control mechanisms operating on Stroop congruent and affordances congruent trials under conditions of high and low cognitive control requirements. We hypothesized that task control is employed in both tasks. One-hundred and twenty-three participants performed an affordances task and two blocks of a Stroop task, each requiring a different level of task control (high vs. low). In a hierarchical regression model, we found a significant and specific correlation between affordances congruent and Stroop congruent conditions only in the high-control block, designed to greatly engage participants' task control, thus linking the task control mechanism in both tasks. These results indicate that task control underlies diverse modalities of response (visuomotor and linguistic), independently of other conflict types. We suggest that the affordances task may serve as a supplementary tool for the assessment of task control in the lab.