Time course differences between bilinguals and monolinguals in the Simon task

In the Simon task, individuals need to indicate the colour of the target stimulus while ignoring its spatial location. The Simon Effect refers to the finding that participants respond more quickly when the target stimulus and response effector are spatially compatible compared to when they are not. Thus, to optimize performance in the Simon task, individuals need to ignore the task-irrelevant (spatial) information and attend to the task-relevant (colour) information. Interestingly, it has been reported that bilinguals are faster than monolinguals in the Simon task and that they exhibit a smaller Simon effect. The present study investigates whether this so-called bilingual advantage is due to bilinguals being better at ignoring task-irrelevant information, or better at activating task-relevant information, or both. In a button-press version of the task, we do not observe a bilingual advantage, but in a reach-to-touch paradigm, we find that bilinguals suppress task-irrelevant information for longer and activate task-relevant information sooner