Arbitrary sensory-motor mapping during object manipulation in healthy persons

Background: Grasping and lifting an object is a basic tool in everyday life. In the following experiments we tested the ability of healthy humans to establish an association between arbitrary sensory cues and the weight of an object. Methods: 10 right-handed healthy subjects accomplished a series of grip-lift tasks of an instrumented object with each hand. In a first experiment, participants lifted two objects of equal visual appearance which unexpectedly and randomly changed their weight. In two subsequent experiments, the change in object weight was indicated by cues, which were presented i) visually or ii) au…