Anvesh Naik, a PhD student with Dr. Ambike, found that healthy young adults alter their grip on an object up to 5 seconds before moving the object. This finding could reflect the capacity and flexibility of control of a healthy system. How would the system of an older individual fare in comparison? Would a deficit in anticipatory grasp control explain the well-known dexterity loss in older individuals? Click here for the paper.
Dr. Ambike, in collaboration with Dr. Jaebum Park (Seoul National University, South Korea), studied the finger forces exerted by young adults on an expanding handle! The forces change systematically as the handle changes shape. Analysis showed that our nervous system controls the apparent stiffness (i.e., springiness of the fingertip) and referent position (i.e., where the fingertip would end up if the object magically disappeared from the hand) of each finger to ensure a stable grasp. Furthermore, these control variables cooperate with each other – unwanted changes in any variable are nullified by compensatory changes in other variables – all in service of keeping the position and orientation of the hand-held object. These results are cutting-edge, fundamental contributions to the motor control of prehension. Click here for the paper.