SANTELLO, M.; Arizona State University: Control of the hand: coordination of multiple variables in the kinematic, kinetic and EMG domain

The hand is one of the most fascinating and sophisticated motor systems. The hand�s complex biomechanical and neural architecture poses important and challenging questions on the control strategies that underlie the fine coordination of finger movements required by a wide variety of behavioral tasks. Hence, a number of different yet complementary experimental approaches, ranging from recording cortical activity to kinematics of finger movement, has been used to further our understanding of the control of the hand. Experimental evidence from behavioral tasks such as reaching and grasping indicates that the simultaneous coordination of finger motion and forces appears to be characterized by synergistic patterns that reduce the number of available degrees of freedom. Peripheral and central limitations that might underlie these coordination patterns have also been identified at different levels of hand�s control system. I will review this evidence with a particular emphasis on tasks requiring the coordination of multi-finger movements and forces. Findings from current investigations on synchronization of hand muscle motor units and its functional role will also be discussed.