Journal of Neurophysiology, Vol 55, Issue 6 1369-1381, Copyright © 1986 by APS

ARTICLES

Central programming of postural movements: adaptation to altered support-surface configurations

F. B. Horak and L. M. Nashner

We studied the extent to which automatic postural actions in standing human subjects are organized by a limited repertoire of central motor programs. Subjects stood on support surfaces of various lengths, which forced them to adopt different postural movement strategies to compensate for the same external perturbations. We assessed whether a continuum or a limited set of muscle activation patterns was used to produce different movement patterns and the extent to which movement patterns were influenced by prior experience. Exposing subjects standing on a normal support surface to brief forward and backward horizontal surface perturbations elicited relatively stereotyped patterns of leg and trunk muscle activation with 73- to 110-ms latencies. Activity began in the ankle joint muscles and then radiated in sequence to thigh and then trunk muscles on the same dorsal or ventral aspect of the body. This activation pattern exerted compensatory torques about the ankle joints, which restored equilibrium by moving the body center of mass forward or backward. This pattern has been termed the ankle strategy because it restores equilibrium by moving the body primarily around the ankle joints. To successfully maintain balance while standing on a support surface short in relation to foot length, subjects activated leg and trunk muscles at similar latencies but organized the activity differently. The trunk and thigh muscles antagonistic to those used in the ankle strategy were activated in the opposite proximal-to-distal sequence, whereas the ankle muscles were generally unresponsive. This activation pattern produced a compensatory horizontal shear force against the support surface but little, if any, ankle torque. This pattern has been termed the hip strategy, because the resulting motion is focused primarily about the hip joints. Exposing subjects to horizontal surface perturbations while standing on support surfaces intermediate in length between the shortest and longest elicited more complex postural movements and associated muscle activation patterns that resembled ankle and hip strategies combined in different temporal relations. These complex postural movements were executed with combinations of torque and horizontal shear forces and motions of ankle and hip joints. During the first 5-20 practice trials immediately following changes from one support surface length to another, response latencies were unchanged. The activation patterns, however, were complex and resembled the patterns observed during well-practiced stance on surfaces of intermediate lengths.(ABSTRACT TRUNCATED AT 400 WORDS)

This article has been cited by other articles:

				T. D. J. Welch and L. H. Ting A Feedback Model Reproduces Muscle Activity During Human Postural Responses to Support-Surface Translations J Neurophysiol, February 1, 2008; 99(2): 1032 - 1038. [Abstract] [Full Text] [PDF]

				Y.-C. Pai and T. S Bhatt Repeated-Slip Training: An Emerging Paradigm for Prevention of Slip-Related Falls Among Older Adults Physical Therapy, November 1, 2007; 87(11): 1478 - 1491. [Abstract] [Full Text] [PDF]

				G. Torres-Oviedo and L. H. Ting Muscle Synergies Characterizing Human Postural Responses J Neurophysiol, October 1, 2007; 98(4): 2144 - 2156. [Abstract] [Full Text] [PDF]

				P.H.J.A. Nieuwenhuijzen and J. Duysens Proactive and Reactive Mechanisms Play a Role in Stepping on Inverting Surfaces During Gait J Neurophysiol, October 1, 2007; 98(4): 2266 - 2273. [Abstract] [Full Text] [PDF]

				I. Melzer, I. Kurz, D. Shahar, M. Levi, and L. Oddsson Application of the voluntary step execution test to identify elderly fallers Age Ageing, September 1, 2007; 36(5): 532 - 537. [Abstract] [Full Text] [PDF]

				S. Van Deun, F. F. Staes, K. H. Stappaerts, L. Janssens, O. Levin, and K. K.H. Peers Relationship of Chronic Ankle Instability to Muscle Activation Patterns During the Transition From Double-Leg to Single-Leg Stance Am. J. Sports Med., February 1, 2007; 35(2): 274 - 281. [Abstract] [Full Text] [PDF]

				Y. P. Ivanenko, R. E. Poppele, and F. Lacquaniti Motor Control Programs and Walking Neuroscientist, August 1, 2006; 12(4): 339 - 348. [Abstract] [PDF]

				G. L. Onambele, M. V. Narici, and C. N. Maganaris Calf muscle-tendon properties and postural balance in old age J Appl Physiol, June 1, 2006; 100(6): 2048 - 2056. [Abstract] [Full Text] [PDF]

				T. Bhatt, E. Wang, and Y.-C. Pai Retention of Adaptive Control Over Varying Intervals: Prevention of Slip- Induced Backward Balance Loss During Gait J Neurophysiol, May 1, 2006; 95(5): 2913 - 2922. [Abstract] [Full Text] [PDF]

				T. Kiemel, K. S. Oie, and J. J. Jeka Slow Dynamics of Postural Sway Are in the Feedback Loop J Neurophysiol, March 1, 2006; 95(3): 1410 - 1418. [Abstract] [Full Text] [PDF]

				C. Gruneberg, J. Duysens, F. Honegger, and J.H.J. Allum Spatio-Temporal Separation of Roll and Pitch Balance-Correcting Commands in Humans J Neurophysiol, November 1, 2005; 94(5): 3143 - 3158. [Abstract] [Full Text] [PDF]

				A. Goldberg, M. E. Hernandez, and N. B. Alexander Trunk Repositioning Errors Are Increased in Balance-Impaired Older Adults J. Gerontol. A Biol. Sci. Med. Sci., October 1, 2005; 60(10): 1310 - 1314. [Abstract] [Full Text] [PDF]

				T. Bhatt and Y.-C. Pai Long-Term Retention of Gait Stability Improvements J Neurophysiol, September 1, 2005; 94(3): 1971 - 1979. [Abstract] [Full Text] [PDF]

				S Colnat-Coulbois, G C Gauchard, L Maillard, G Barroche, H Vespignani, J Auque, and P. P Perrin Bilateral subthalamic nucleus stimulation improves balance control in Parkinson's disease J. Neurol. Neurosurg. Psychiatry, June 1, 2005; 76(6): 780 - 787. [Abstract] [Full Text] [PDF]

				T. W Cacciatore, F. B Horak, and S. M Henry Improvement in Automatic Postural Coordination Following Alexander Technique Lessons in a Person With Low Back Pain Physical Therapy, June 1, 2005; 85(6): 565 - 578. [Abstract] [Full Text] [PDF]

				N. Benjuya, I. Melzer, and J. Kaplanski Aging-Induced Shifts From a Reliance on Sensory Input to Muscle Cocontraction During Balanced Standing J. Gerontol. A Biol. Sci. Med. Sci., February 1, 2004; 59(2): M166 - 171. [Abstract] [Full Text] [PDF]

				K. Masani, M. R. Popovic, K. Nakazawa, M. Kouzaki, and D. Nozaki Importance of Body Sway Velocity Information in Controlling Ankle Extensor Activities During Quiet Stance J Neurophysiol, December 1, 2003; 90(6): 3774 - 3782. [Abstract] [Full Text] [PDF]

				Y.-C. Pai, J. D. Wening, E. F. Runtz, K. Iqbal, and M. J. Pavol Role of Feedforward Control of Movement Stability in Reducing Slip-Related Balance Loss and Falls Among Older Adults J Neurophysiol, August 1, 2003; 90(2): 755 - 762. [Abstract] [Full Text] [PDF]

				M.-L. Mille, M. W. Rogers, K. Martinez, L. D. Hedman, M. E. Johnson, S. R. Lord, and R. C. Fitzpatrick Thresholds for Inducing Protective Stepping Responses to External Perturbations of Human Standing J Neurophysiol, August 1, 2003; 90(2): 666 - 674. [Abstract] [Full Text] [PDF]

				R. J. Peterka Sensorimotor Integration in Human Postural Control J Neurophysiol, September 1, 2002; 88(3): 1097 - 1118. [Abstract] [Full Text] [PDF]

				D Cattaneo, F Marazzini, A Crippa, and R Cardini Do static or dynamic AFOs improve balance? Clinical Rehabilitation, August 1, 2002; 16(8): 894 - 899. [Abstract] [PDF]

				T Paillard, C Costes-Salon, C Lafont, and P Dupui Are there differences in postural regulation according to the level of competition in judoists? Br. J. Sports Med., August 1, 2002; 36(4): 304 - 305. [Abstract] [Full Text] [PDF]

				D. S. Marigold and A. E. Patla Strategies for Dynamic Stability During Locomotion on a Slippery Surface: Effects of Prior Experience and Knowledge J Neurophysiol, July 1, 2002; 88(1): 339 - 353. [Abstract] [Full Text] [PDF]

				Y. Ohki, B. B. Edin, and R. S. Johansson Predictions Specify Reactive Control of Individual Digits in Manipulation J. Neurosci., January 15, 2002; 22(2): 600 - 610. [Abstract] [Full Text] [PDF]

				F. O. BLACK What Can Posturography Tell Us About Vestibular Function? Ann. N.Y. Acad. Sci., October 1, 2001; 942(1): 446 - 464. [Abstract] [Full Text] [PDF]

				D. A. Winter, A. E. Patla, S. Rietdyk, and M. G. Ishac Ankle Muscle Stiffness in the Control of Balance During Quiet Standing J Neurophysiol, June 1, 2001; 85(6): 2630 - 2633. [Abstract] [Full Text] [PDF]

				S. M. Henry, J. Fung, and F. B. Horak Effect of Stance Width on Multidirectional Postural Responses J Neurophysiol, February 1, 2001; 85(2): 559 - 570. [Abstract] [Full Text] [PDF]

				J. R. Lackner, E. Rabin, and P. DiZio Fingertip Contact Suppresses the Destabilizing Influence of Leg Muscle Vibration J Neurophysiol, November 1, 2000; 84(5): 2217 - 2224. [Abstract] [Full Text] [PDF]

				J. W. McChesney and M. H. Woollacott The Effect of Age-Related Declines in Proprioception and Total Knee Replacement on Postural Control J. Gerontol. A Biol. Sci. Med. Sci., November 1, 2000; 55(11): 658M - 666. [Abstract] [Full Text]

				S. G. Kirker, J. R Jenner, D. S Simpson, and A. M Wing Changing patterns of postural hip muscle activity during recovery from stroke Clinical Rehabilitation, June 1, 2000; 14(6): 618 - 626. [Abstract] [PDF]

				S G B Kirker, D S Simpson, J R Jenner, and A M Wing Stepping before standing: hip muscle function in stepping and standing balance after stroke J. Neurol. Neurosurg. Psychiatry, April 1, 2000; 68(4): 458 - 464. [Abstract] [Full Text] [PDF]

				A. S Pollock, B. R Durward, P. J Rowe, and J. P Paul What is balance? Clinical Rehabilitation, April 1, 2000; 14(4): 402 - 406. [Abstract] [PDF]

				G. M. Earhart and P. S. G. Stein Scratch-Swim Hybrids in the Spinal Turtle: Blending of Rostral Scratch and Forward Swim J Neurophysiol, January 1, 2000; 83(1): 156 - 165. [Abstract] [Full Text] [PDF]

				V. S. Mercer and S. A Sahrmann Postural Synergies Associated With a Stepping Task Physical Therapy, December 1, 1999; 79(12): 1142 - 1152. [Abstract] [Full Text] [PDF]

				A. A. Sharp, E. Ma, and A. Bekoff Developmental Changes in Leg Coordination of the Chick at Embryonic Days 9, 11, and 13: Uncoupling of Ankle Movements J Neurophysiol, November 1, 1999; 82(5): 2406 - 2414. [Abstract] [Full Text] [PDF]

				C. C. Raasch and F. E. Zajac Locomotor Strategy for Pedaling: Muscle Groups and Biomechanical Functions J Neurophysiol, August 1, 1999; 82(2): 515 - 525. [Abstract] [Full Text] [PDF]

				K. Hase and R. B. Stein Turning Strategies During Human Walking J Neurophysiol, June 1, 1999; 81(6): 2914 - 2922. [Abstract] [Full Text] [PDF]

				M. Hadders-Algra, E. Brogren, M. Katz-Salamon, and H. Forssberg Periventricular leucomalacia and preterm birth have different detrimental effects on postural adjustments Brain, April 1, 1999; 122(4): 727 - 740. [Abstract] [Full Text] [PDF]

				S. M. Henry, J. Fung, and F. B. Horak EMG Responses to Maintain Stance During Multidirectional Surface Translations J Neurophysiol, October 1, 1998; 80(4): 1939 - 1950. [Abstract] [Full Text] [PDF]

				D. A. Winter, A. E. Patla, F. Prince, M. Ishac, and K. Gielo-Perczak Stiffness Control of Balance in Quiet Standing J Neurophysiol, September 1, 1998; 80(3): 1211 - 1221. [Abstract] [Full Text] [PDF]

				Z. M. Al-Zamil Use of Long Loop Reflexes to Assess Postural Control Following Stroke Neurorehabil Neural Repair, January 1, 1998; 12(1): 23 - 28. [Abstract] [PDF]

				L. Konradsen, M. Voigt, and C. Hojsgaard Ankle Inversion Injuries: The Role of the Dynamic Defense Mechanism Am. J. Sports Med., January 1, 1997; 25(1): 54 - 58. [Abstract] [PDF]

				V Brooks, F Hilperath, M Brooks, H G Ross, and H J Freund Learning "what" and "how" in a human motor task. Learn. Mem., January 1, 1995; 2(5): 225 - 242. [Abstract] [PDF]