Reward prospect affects strategic adjustments in stop signal task

Abstract

Interaction with the environment requires us to predict the potential reward that will follow our choices. Rewards could change depending on the context and our behavior adapts accordingly. Previous studies have shown that, depending on reward regimes, actions can be facilitated (i.e., increasing the reward for response) or interfered (i.e., increasing the reward for suppression). Here we studied how the change in reward perspective can influence subjects’ adaptation strategy. Students were asked to perform a modified version of the Stop-Signal task. Specifically, at the beginning of each trial, a Cue Signal informed subjects of the value of the reward they would receive; in one condition, Go Trials were rewarded more than Stop Trials, in another, Stop Trials were rewarded more than Go Trials, and in the last, both trials were rewarded equally. Subjects participated in a virtual competition, and the reward consisted of points to be earned to climb the leaderboard and win (as in a video game contest). The sum of points earned was updated with each trial. After a learning phase in which the three conditions were presented separately, each subject performed 600 trials testing phase in which the three conditions were randomly mixed. Based on the previous studies, we hypothesized that subjects could employ different strategies to perform the task, including modulating inhibition efficiency, adjusting response speed, or employing a constant behavior across contexts. We found that to perform the task, subjects preferentially employed a strategy-related speed of response adjustment, while the duration of the inhibition process did not change significantly across the conditions. The investigation of strategic motor adjustments to reward’s prospect is relevant not only to understanding how action control is typically regulated, but also to work on various groups of patients who exhibit cognitive control deficits, suggesting that the ability to inhibit can be modulated by employing reward prospects as motivational factors.

Motivational context and neurocomputation of stop expectation moderate early attention responses supporting proactive inhibitory control

“…Overall, these results are consistent with prior findings that SST performance and measures of response inhibition are influenced by motivational context; participants respond more accurately on stop trials and respond more slowly overall as rewards and punishments increasingly favor stop accuracy over speed (Leotti and Wager, 2010). They are also consistent with findings that reward can enhance both proactive inhibitory control (slower Go RTs, physiological evidence of enhanced attention) (Chiew and Braver, 2014;Giuffrida et al, 2023) and reactive inhibitory control (lower SSRTs) (Herrera et al, 2019). However, we did not find any significant impact of motivation stake or valence on individuals' learning parameters that capture initial, preobservation expectations and perceived stability of the stop signal frequency.…”

“…Yet, the degree to which proactive inhibitory control mechanisms are modulated by motivational factors (e.g., reward, punishment) remains poorly understood. Recent behavioral studies have shown that reward motivation can improve inhibitory control processes (Chiew and Braver, 2014 ; Herrera et al, 2014 , 2019 ; Giuffrida et al, 2023 ), and, in line with modulation of proactive inhibitory control, reward incentives can enhance transient neural responses of early attention to go stimuli prior to inhibitory cues (Schevernels et al, 2015 ; Langford et al, 2016 ). However, these studies did not examine the impact of motivation on the predictive neurocognitive processes supporting inhibitory performance.…”