Dissociating processes underlying cognitive control and value-based attention: A reach tracking study

Our abilities to focus on a goal while ignoring distractors (cognitive control), and to orient attention towards rewarding stimuli (value-based attention) are critical for survival. Cognitive control encompasses multistage processes such as conflict monitoring, response threshold adjustment, and response selection (Shenhav et al., 2013). However, little is known about how each process interacts with value-driven attention. To address this gap, we developed a modified Flanker task combined with a reach-tracking paradigm. Participants reached to a target on the right or left side of the screen as instructed by a central arrow that was flanked by congruent, incongruent or neutral distractors. To manipulate value-based attention, the flankers were rendered in colors that had pre-trained associations with positive, negative, or no monetary outcomes. Previous studies suggest that, in the reach tracking paradigm, the initiation latency (time taken to initiate the movement after stimulus presentation) captures adjustments in response threshold, while the reach curvature (degree of deviation in the reach trajectory from the direct path to the target) captures response selection (e.g., Erb et al., 2016). We found that these two measures were differentially affected by distractor congruency and value. Initiation latency was reduced by congruent relative to neutral flankers, suggesting that congruency lowered response threshold. This reduction was attenuated by positive-reward compared to no-reward conditions. In contrast, curvature was increased on incongruent relative to neutral trials, suggesting that incongruent distractors interfere with response selection, and this effect was not affected by flanker value. Together, it appears that both congruent and incongruent trials modulate different cognitive control processes, response threshold adjustment and response selection respectively, whereas reward only modulates the former. Overall, this study uncovers the potential interactions underlying our cognitive control and value-based attention systems.