Welcome to the Huffines Institute Blog, where the best and brightest students in the Texas A&M Department of Health and Kinesiology get the chance to showcase their research. This week's article is written by Jason Boyle, Ph.D, and discusses control of wrist and arm movements of varying difficulty.
Our muscles are controlled by “motor units”, which each consist of a neuron, and the muscle fiber(s) it activates or “innervates”. The muscle that responds is termed an “effector”. Brain mapping studies have shown that a disproportionate area of the motor cortex governs certain effectors of the body. For example, your fingers, lips, and tongue are highly innervated organs that can execute complex movement patterns, but your toes are not quite as skilled. So naturally this is an ideal system to operate under, since our daily activities require that we manipulate objects with our hands and speak with our mouth. Likewise, as technology advances, our daily interaction with electronic devices has become almost second nature. However, this interaction (movement pattern) can be altered by visual manipulations to our perceptual system.
- Balakrishnan, I.L., & MacKenzie, I.S. (1997). Performance differences in the fingers, wrist, and forearm in computer input control. In Proceedings of the CHT ’97 Conference on Human Factors in Computing Systems. New York ACM, 303-310.
- Kovacs, A. J., Buchanan, J. J., & Shea, C.H. (2008). Perceptual influences on Fitts’ law.Experimental Brain Research, 190, 99-103.http://download.springer.com/static/pdf/661/art%253A10.1007%252Fs00221-008-1497-3.pdf?auth66=1403300714_968e696260081b7da177f2e232c964f6&ext=.pdf