Fig. 1.

The center-out task with accompanying speed profile during overt wrist movement. The subject controls the 2-dimensional (2-D) cursor position using wrist movements. The cursor needs to go to the center and stay there for a hold period until the peripheral target appears. Then the cursor moves to the target and stays there for another hold period to complete the trial successfully. The target changes color when hit by the cursor and disappears when the holding period has finished. There was a 1-s interval between trials. The bottom trace shows the speed profile of the cursor from a representative trial, and the dotted lines delimit the premovement/planning period within which a time window was identified and used for decoding the intended movement direction for overt movement trials.