Fig. 1

Stop-Signal Task. In Go trials, a start cue instructs participants to press and hold a switch with their right index finger. The start cue is then replaced by a fixation point (for 350 ms) before two target items appear (for 300 ms) to the right and left of the fixation point. A go-cue, a white bar, then replaces the fixation point. If the bar is horizontal or vertical, participants were to select (by touch) the right or left target item, respectively, within a 900 ms time window. If the correct target was not selected within the time window, an error-signal was shown, and the trial was considered as an error. Within Stop trials, events were the same until go-cue onset, however, following a variable delay, a stop signal (multi-coloured image) replaced the go-cue. This stop-signal (multi-coloured images of various objects) instructed participants to inhibit their response and keep pressing the switch. Switch release was considered as an error in Stop trials