Individual differences in the effects of salience and reward on impulse control and action selection

Impulse control and adequate decision making are vital functions when it comes to detection and adherence to societal rules, especially in critical circumstances such as the Covid pandemic. In the current study we tested the hypothesis that increasing the salience of environmental cues would be most effective in improving impulse control, as assessed in a stop-signal task, in subjects with low environmental susceptibility as indexed by low pre-stimulus EEG alpha power. In addition, we anticipated that an external-reward intervention improves performance during a Go/No go task, especially in individuals with low task-induced motivation as indexed by low theta/ beta power ratios. High salience of stop signals enhanced stopping performance but there was no difference in responsivity to the salience intervention between participants with high and low EEG alpha power. Individuals with low theta/ beta power ratios responded more accurately when rewards were at stake. Together these results suggest that increasing the salience of external cues may help impulse control in general, whereas the effectiveness of external-reward interventions is higher in individuals with low task-induced motivation.