A test of torque-control and equilibrium-point models of motor control

• Published in: Human movement science Vol. 19; no. 6; pp. 925 - 931
• Main Author: Gottlieb, Gerald L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.12.2000; Elsevier
• Subjects: Biological and medical sciences; Equilibrium point hypothesis; Fundamental and applied biological sciences. Psychology; Human elbow movement; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; Torque control; Vertebrates: nervous system and sense organs; Voluntary movement; Equilibrium point hypothesis; 2330; Human elbow movement; Voluntary movement; Torque control; Biomechanics; Human; Freedom degree; Voluntary control; Body movement; Upper limb; Motor control; Elbow; Equilibrium; Equilibrium point
• ISSN: 0167-9457; 1872-7646
• DOI: 10.1016/S0167-9457(01)00040-9

Based upon predictions of equilibrium-point (EP) models of motor control, a recent article by Jaric et al. (1999) [ Human Movement Sciences, 18, 49–66] reported that the peak velocity (PV) of an inertially loaded single degree-of-freedom elbow movement was not altered to a statistically distinguishable degree by the accuracy of the subject's expectation about the size of the load. They concluded that their results confirmed their EP models and were incompatible with what they described as torque-control models. A review of the literature and analysis of a more extensive set of data does not support that conclusion. To the contrary, if the actual load is heavier (or lighter) than expected, it is moved more slowly (or faster) than it would have been, had expectation matched reality. Torque-control models predict those consequences, EP models do not.