This finding adds to our understanding of the control of bimanual movements in the human brain: Each hemisphere can independently control the contralateral hand, while modulating what it does based on the ipsilateral movement.

During bimanual movements, both the contra-lateral movement and the (non-linear) bimanual combination is encoded. But the representation of the ipsilateral hand (which is strong during unimanual movements) disappears! The traditional bimanual congruency effect is present in higher-level areas.