Change of a Motor Synergy for Dampening Hand Vibration Depending on a Task Difficulty

Overview

Journal Exp Brain Res

Specialty Neurology

Date 2014 Jun 5

PMID 24894587

Citations 2

Authors

Shunta Togo

Takahiro Kagawa

Yoji Uno

Affiliations

Soon will be listed here.

Abstract

The present study investigated the relationship between the number of usable degrees of freedom (DOFs) and joint coordination during a human-dampening hand vibration task. Participants stood on a platform generating an anterior-posterior directional oscillation and held a water-filled cup. Their usable DOFs were changed under the following conditions of limb constraint: (1) no constraint; (2) ankle constrained; and (3) ankle-knee constrained. Kinematic whole-body data were recorded using a three-dimensional position measurement system. The jerk of each body part was evaluated as an index of oscillation intensity. To quantify joint coordination, an uncontrolled manifold (UCM) analysis was applied and the variance of joints related to hand jerk divided into two components: a UCM component that did not affect hand jerk and an orthogonal (ORT) component that directly affected hand jerk. The results showed that hand jerk when the task used a cup filled with water was significantly smaller than when a cup containing stones was used, regardless of limb constraint condition. Thus, participants dampened their hand vibration utilizing usable joint DOFs. According to UCM analysis, increasing the oscillation velocity and the decrease in usable DOFs by the limb constraints led to an increase of total variance of the joints and the UCM component, indicating that a synergy-dampening hand vibration was enhanced. These results show that the variance of usable joint DOFs is more fitted to the UCM subspace when the joints are varied by increasing the velocity and limb constraints and suggest that humans adopt enhanced synergies to achieve more difficult tasks.

Citing Articles

Normalized Index of Synergy for Evaluating the Coordination of Motor Commands.

Togo S, Imamizu H PLoS One. 2015; 10(10):e0140836.

PMID: 26474043 PMC: 4608756. DOI: 10.1371/journal.pone.0140836.

Control model for dampening hand vibrations using information of internal and external coordinates.

Togo S, Kagawa T, Uno Y PLoS One. 2015; 10(4):e0125464.

PMID: 25876037 PMC: 4395142. DOI: 10.1371/journal.pone.0125464.

References

Wu J, McKay S, Angulo-Barroso R . Center of mass control and multi-segment coordination in children during quiet stance. Exp Brain Res. 2009; 196(3):329-39. DOI: 10.1007/s00221-009-1852-z. View

Adamovich S, Archambault P, Ghafouri M, Levin M, Poizner H, Feldman A . Hand trajectory invariance in reaching movements involving the trunk. Exp Brain Res. 2001; 138(3):288-303. DOI: 10.1007/s002210100694. View

Danna-Dos-Santos A, Slomka K, Zatsiorsky V, Latash M . Muscle modes and synergies during voluntary body sway. Exp Brain Res. 2007; 179(4):533-50. DOI: 10.1007/s00221-006-0812-0. View

Latash M, Scholz J, Schoner G . Motor control strategies revealed in the structure of motor variability. Exerc Sport Sci Rev. 2002; 30(1):26-31. DOI: 10.1097/00003677-200201000-00006. View

Black D, Smith B, Wu J, Ulrich B . Uncontrolled manifold analysis of segmental angle variability during walking: preadolescents with and without Down syndrome. Exp Brain Res. 2007; 183(4):511-21. DOI: 10.1007/s00221-007-1066-1. View

Verrel J . Distributional properties and variance-stabilizing transformations for measures of uncontrolled manifold effects. J Neurosci Methods. 2010; 191(2):166-70. DOI: 10.1016/j.jneumeth.2010.06.016. View

Scholz J, Schoner G, Hsu W, Jeka J, Horak F, Martin V . Motor equivalent control of the center of mass in response to support surface perturbations. Exp Brain Res. 2007; 180(1):163-79. DOI: 10.1007/s00221-006-0848-1. View

Latash M . Stages in learning motor synergies: a view based on the equilibrium-point hypothesis. Hum Mov Sci. 2010; 29(5):642-54. PMC: 2891849. DOI: 10.1016/j.humov.2009.11.002. View

Morasso P, Casadio M, Mohan V, Zenzeri J . A neural mechanism of synergy formation for whole body reaching. Biol Cybern. 2009; 102(1):45-55. DOI: 10.1007/s00422-009-0349-y. View

10.

Tseng Y, Scholz J, Schoner G, Hotchkiss L . Effect of accuracy constraint on joint coordination during pointing movements. Exp Brain Res. 2003; 149(3):276-88. DOI: 10.1007/s00221-002-1357-5. View

11.

Hodges N, Hayes S, Horn R, Williams A . Changes in coordination, control and outcome as a result of extended practice on a novel motor skill. Ergonomics. 2005; 48(11-14):1672-85. DOI: 10.1080/00140130500101312. View

12.

Yen J, Auyang A, Chang Y . Joint-level kinetic redundancy is exploited to control limb-level forces during human hopping. Exp Brain Res. 2009; 196(3):439-51. DOI: 10.1007/s00221-009-1868-4. View

13.

Fukson O, Berkinblit M, Feldman A . The spinal frog takes into account the scheme of its body during the wiping reflex. Science. 1980; 209(4462):1261-3. DOI: 10.1126/science.7403886. View

14.

Robert T, Bennett B, Russell S, Zirker C, Abel M . Angular momentum synergies during walking. Exp Brain Res. 2009; 197(2):185-97. DOI: 10.1007/s00221-009-1904-4. View

15.

Newell K, Vaillancourt D . Dimensional change in motor learning. Hum Mov Sci. 2001; 20(4-5):695-715. DOI: 10.1016/s0167-9457(01)00073-2. View

16.

Scholz J, Schoner G . The uncontrolled manifold concept: identifying control variables for a functional task. Exp Brain Res. 1999; 126(3):289-306. DOI: 10.1007/s002210050738. View

17.

Latash M, Scholz J, Schoner G . Toward a new theory of motor synergies. Motor Control. 2007; 11(3):276-308. DOI: 10.1123/mcj.11.3.276. View

18.

Newell K, Broderick M, Deutsch K, Slifkin A . Task goals and change in dynamical degrees of freedom with motor learning. J Exp Psychol Hum Percept Perform. 2003; 29(2):379-87. DOI: 10.1037/0096-1523.29.2.379. View

19.

Ko Y, Challis J, Newell K . Learning to coordinate redundant degrees of freedom in a dynamic balance task. Hum Mov Sci. 2003; 22(1):47-66. DOI: 10.1016/s0167-9457(02)00177-x. View

20.

Yang J, Scholz J, Latash M . The role of kinematic redundancy in adaptation of reaching. Exp Brain Res. 2006; 176(1):54-69. PMC: 1945250. DOI: 10.1007/s00221-006-0602-8. View