A simple rule of thumb for elegant prehension

Publication Summary

Abstract Reaching out to an object (prehension) is a deceptively elegant and skilled behavior. The movement prior to object contact can be described as having two components [1], the movement of the hand to an appropriate location for gripping the object, the component, and the opening and closing of the aperture between the fingers as they prepare to grip the target, the grasp component. The component is sensitive to the size of the object, so that a larger aperture is formed for wider objects [1]; the maximum aperture (MGA) is a little wider than the width of the target object and occurs later in the movement for larger objects [1, 2]. We present a simple model that can account for the temporal relationship between the transport and components. We report the results of an experiment providing empirical support for our rule of thumb. The model provides a simple, but plausible, account of a neural control strategy that has been the center of debate over the last two decades.