The role of motor action in anticipatory postural adjustments studied with self-induced and externally triggered perturbations

This study investigated the relation between the magnitude of a motor action triggering a postural perturbation and the magnitude of anticipatory postural adjustments. Subjects stood on a force platform and held, in extended arms, a balloon with a 2.2-kg load suspended on a rigid cord. In different series, unloadings were induced by fast bilateral shoulder abduction movements, by popping the balloon with a tack taped to the subject's right middle finger, or by the experimenter popping the balloon. Anticipatory postural adjustments were seen during all self-initiated unloadings as changes in the level of activation of postural muscles and in displacements of the center of pressure. However, absolute values of these changes were significantly smaller in the series with balloon popping as compared to the series with shoulder abductions. Such reactions were absent when the unloading was triggered by the experimenter. We conclude that a self-triggered perturbation is always associated with anticipatory postural adjustments, while the magnitude of the adjustments may be scaled with respect to the magnitude of a motor action used to induce the perturbation.

[1]  J. Foley The co-ordination and regulation of movements , 1968 .

[2]  G. Jones,et al.  Observations on the control of stepping and hopping movements in man , 1971, The Journal of physiology.

[3]  G. Jones,et al.  Muscular control of landing from unexpected falls in man , 1971, The Journal of physiology.

[4]  S. Rossignol Startle responses recorded in the leg of man. , 1975, Electroencephalography and clinical neurophysiology.

[5]  S. Bouisset,et al.  A sequence of postural movements precedes voluntary movement , 1981, Neuroscience Letters.

[6]  L. Nashner,et al.  Properties of postural adjustments associated with rapid arm movements. , 1982, Journal of neurophysiology.

[7]  J. Allum Organization of stabilizing reflex responses in tibialis anterior muscles following ankle flexion perturbations of standing man , 1983, Brain Research.

[8]  M. E. Anderson,et al.  The effects of movement velocity, mass displaced, and task certainty on associated postural adjustments made by normal and hemiplegic individuals. , 1984, Journal of neurology, neurosurgery, and psychiatry.

[9]  M. Hallett,et al.  Postural adjustments associated with rapid voluntary arm movements 1. Electromyographic data. , 1984, Journal of neurology, neurosurgery, and psychiatry.

[10]  B. Day,et al.  Associated postural adjustments in Parkinson's disease. , 1986, Journal of neurology, neurosurgery, and psychiatry.

[11]  A. Thorstensson,et al.  Fast voluntary trunk flexion movements in standing: primary movements and associated postural adjustments. , 1986, Acta physiologica Scandinavica.

[12]  S. Bouisset,et al.  Postural adjustments associated with rapid voluntary arm movements in patients with Parkinson's disease. , 1987, Advances in neurology.

[13]  M. Hallett,et al.  Postural adjustments associated with rapid voluntary arm movements. II. Biomechanical analysis. , 1988, Journal of neurology, neurosurgery, and psychiatry.

[14]  F. Horak,et al.  Influence of central set on human postural responses. , 1989, Journal of neurophysiology.

[15]  F. Lacquaniti,et al.  The role of preparation in tuning anticipatory and reflex responses during catching , 1989, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[16]  S. Bouisset,et al.  Segmental Movement as a Perturbation to Balance? Facts and Concepts , 1990 .

[17]  K. Hayes,et al.  Changes in centre of pressure of ground reaction forces prior to rapid arm movement in normal subjects and patients with cerebellar ataxia. , 1992, Clinical biomechanics.

[18]  J. Massion Movement, posture and equilibrium: Interaction and coordination , 1992, Progress in Neurobiology.

[19]  L. Gerilovsky,et al.  Self-generated rapid taps directed to the opposite forearm in man: anticipatory reduction in the muscle activity of the target arm , 1993, Neuroscience Letters.

[20]  P. Ashby,et al.  The processing of human ballistic movements explored by stimulation over the cortex. , 1994, The Journal of physiology.

[21]  F. Horak,et al.  Modification of postural responses and step initiation: evidence for goal-directed postural interactions. , 1994, Journal of neurophysiology.

[22]  M. Latash,et al.  Anticipatory postural adjustments during self inflicted and predictable perturbations in Parkinson's disease. , 1995, Journal of neurology, neurosurgery, and psychiatry.

[23]  M. Latash,et al.  The relation between posture and movement: A study of a simple synergy in a two-joint task , 1995 .

[24]  M. Latash,et al.  Directional specificity of postural muscles in feed-forward postural reactions during fast voluntary arm movements , 2004, Experimental Brain Research.

[25]  J. Massion,et al.  Forward and backward axial synergies in man , 2004, Experimental Brain Research.

[26]  J. Massion,et al.  Coordination between posture and movement in a bimanual load lifting task: putative role of a medial frontal region including the supplementary motor area , 2004, Experimental Brain Research.

[27]  J. Massion,et al.  Acquisition of co-ordination between posture and movement in a bimanual task , 2004, Experimental Brain Research.

[28]  L. Nashner,et al.  Relation of automatic postural responses and reaction-time voluntary movements of human leg muscles , 2004, Experimental Brain Research.

[29]  J. Massion,et al.  Postural forearm changes induced by predictable in time or voluntary triggered unloading in man , 2004, Experimental Brain Research.

[30]  V. Dietz,et al.  Body oscillations in balancing due to segmental stretch reflex activity , 2004, Experimental Brain Research.