Sensorymotor Synergies: Fusion of Cutaneous Touch and Proprioception in the Perceived Hand Kinematics

According to classical studies in physiology, muscle spindles and other receptors from joints and tendons provide crucial information on the position of our body and our limbs. Cutaneous cues also provide an important contribution to our sense of position. For example, it is possible to induce a vivid sensation of movement in the anesthetized finger, by stretching the skin around the proximal interphalangeal joint. However, much of proprioceptive literature did not consider the role of tactile interaction with external objects as position and motion cues. Whenever we touch an external, stationary object, the contact forces produce a mechanical deformation of the skin which changes with the hand posture and movement. Therefore, these cutaneous contact cues might also provide proprioceptive information. In this paragraph, evaluated this hypothesis based on recently published experimental data.