Data processing
Matlab was used for offline data processing. For each series (S1 to S6) of the acquisition phase, the mean of the 8 trials was calculated. For the Ret phase, the mean value of all 3 series was used. Mean values were calculated (a) for the mean deviation [°/8 s], which participants received as feedback after each trial, and (b) for the duration [s] participants balanced in ± 4° to the horizontal alignment during each trial.