Balance task
Participants stood shoulder width on the platform of a rocker-board that could rotate forward and backward to a maximum of 20° around a fixed axis and were asked to keep the platform as quiet and horizontal as possible during each of the 48 trials. After each trial, which lasted 8 s, participants received offline feedback on their performance on a screen, standardizing the pause length to 30 s. Feedback reflected the platform position relative to the horizontal alignment and the corresponding mean deviation [°/8 s] from the horizontal line as a single value. Participants were encouraged to minimize this value as much as possible throughout the experiment. Between the series, participants had a pause of 60 s. Aborted trials (leaving the device or holding on) were repeated. A detailed description of the balance device (i.e. rocker-board) was previously provided