Restart errors reaction time of a two-step inhibition process account for the violation of the race model’s independence in multi-effector selective stop signal task

Abstract

Goal-oriented actions often require the coordinated movement of two or more effectors. Sometimes multi-effector movements need to be adjusted according to a continuously changing environment, requiring stopping an effector without interrupting the movement of the others. This form of control has been investigated by the selective Stop Signal Task (SST), requiring the inhibition of an effector of a multicomponent action. This form of selective inhibition has been hypothesized to act through a two-step process, where a temporary global inhibition deactivating all the ongoing motor responses is followed by a restarting process that reactivates only the moving effector. When this form of inhibition takes place, the reaction time (RT) of the moving effector pays the cost of the previous global inhibition. However, it is poorly investigated if and how this cost delays the RT of the effector that was required to be stopped but was erroneously moved (Stop Error trials). Here we measure the Stop Error RT in a group of participants instructed to simultaneously rotate the wrist and lift the foot when a Go Signal occurred, and interrupt both movements (non-selective Stop version) or only one of them (selective Stop version) when a Stop Signal was presented. We presented this task in two experimental conditions to evaluate how different contexts can influence a possible proactive inhibition on the RT of the moving effector in the selective Stop versions. In one context, we provided the foreknowledge of the effector to be inhibited by presenting the same selective or non-selective Stop versions in the same block of trials. In a different context, while providing no foreknowledge of the effector(s) to be stopped, the selective and non-selective Stop versions were intermingled, and the information on the effector to be stopped was delivered at the time of the Stop Signal presentation. We detected a cost in both Correct and Error selective Stop RTs that was influenced by the different task conditions. Results are discussed within the framework of the race model related to the SST, and its relationship with a restart model developed for selective versions of this paradigm.

Reward prospect affects strategic adjustments in stop signal task

“…We estimated a priori the sample size of 14 subjects, on the basis of power 0.90 to detect an effect size in a within-subject design of 0.42 based on partial eta squared (η 2 p ) 0.15 using GPower 3.1.9.7 (Faul et al, 2007(Faul et al, , 2009, as reported in the previous studies employing similar tasks (Mirabella et al, 2008;Andujar et al, 2022;Marc et al, 2023). Eighteen subjects (4 males & 14 females, mean age = 26.5) were recruited for the study.…”

“…This requires, for example, assessing the potential reward that could be obtained in a specific context before deciding whether or not to act, and being able to stop quickly if sudden changes in the environment make the action no longer useful. A widely used experimental paradigm to study choice behavior is the Stop-Signal Task (SST) in both human and non-human primates (Vince, 1948;Logan and Cowan, 1984;Hanes and Carpenter, 1999;Scangos and Stuphorn, 2010;Brunamonti et al, 2012;Pani et al, 2014;Montanari et al, 2017;Schall et al, 2017;Pani et al, 2018;Bardella et al, 2020;Fiori et al, 2020;Giarrocco et al, 2021;Andujar et al, 2022;Hervault et al, 2022;Pani et al, 2022;Bardella et al, 2023;Marc et al, 2023). The SST requires the subjects to respond as quickly as possible when a Go Signal is presented (for example by pressing a button) and to interrupt the response when unpredictably a Stop Signal is presented after a variable time from the Go Signal.…”

“…In the SST, for example, the subjects tend to procrastinate their responses as a Stop Signal could possibly be presented. Depending on the context, both control processes can be affected by different factors, such as attention, reward, and motivation (Engelmann and Pessoa, 2007;Mohanty et al, 2008;Engelmann et al, 2009;Krebs et al, 2009;Pessoa and Engelmann, 2010;Padmala et al, 2011;Stoppel et al, 2011;Marc et al, 2023).…”