Concept: Touch, proprioception, and vision are important sensory components of motor control.
After completing this chapter, you will be able to
Describe the sensory receptors in the skin that provide tactile sensory information to the central nervous system
Discuss several movement-related characteristics influenced by tactile sensory feedback
Describe various types of sensory receptors that provide proprioception information to the central nervous system
Describe several procedures researchers use to investigate the role of proprioception in motor control
Discuss several movement-related characteristics influenced by feedback from the proprioceptors
Describe key anatomical components of the eye and neural pathways for vision
Describe several procedures researchers use to investigate the role of vision in motor control
Discuss motor control issues related to the use of binocular and monocular vision, central and peripheral vision, the perception-action coupling of vision and movement, vision-based movement corrections, and the optical variable tau
When you reach for a glass of water to drink from it, the tactile (i.e., touch), proprioceptive, and visual sensory systems come into play as you carry out the action. Vision helps you locate the glass and grasp it with your hand and fingers. Touch and proprioception help you lift the glass, move it toward your mouth, and not have the glass slip out of your hand. Without the sensory information provided by these key sensory systems, you would have considerably more difficulty carrying out relatively simple tasks like drinking from a glass. You accomplish other everyday skills, such as putting your door key into the keyhole, maneuvering around people as you walk in a hallway, and driving your car with ease, because of the information that touch, proprioception, and vision provide your motor control system. Similarly, sport activities also require and benefit from the roles played by these same sensory systems. For example, to catch a ball, you must see where the ball is, time its arrival to your hand, position your hand in space, and then close your fingers around the ball when it is in your hand.
In all of these skill performance situations, practitioners can benefit from an understanding of the tactile, proprioception, and visual sensory systems in terms of their anatomical and physiological basis, how they influence the control of movement, and the limits they place on human motor skill performance. In the following discussion, we will consider each of these three sensory systems by addressing their anatomical and physiological basis and their relevance to the control of coordinated movement. The intent is to help practitioners establish a foundation on which they can build effective strategies to facilitate skill learning or rehabilitation for the people with whom they work.
Application Problem to Solve When you reach for and grasp a glass of water, how do you know how far to reach, how much force to use to grasp the glass, and how to keep the glass from ...