Experimental design.

(A) Experimental conditions and associated stimuli. S1 and S2 arrow stimuli are shown followed by the required tapping sequence. Shades of grey represent different arrow colours (blue, pink and green) per condition (counterbalanced across participants). Total trial counts are shown below the condition name for left (L) and right (R) hands. Grey dots next to the fingers indicate the thumb-finger tap sequence in each condition. (B) An example trial sequence showing a complex left hand trial.