Abundant Degrees of Freedom Are Not a Problem

in Kinesiology Review
Restricted access

Purchase article

USD $24.95

Student 1 year subscription

USD $41.00

1 year subscription

USD $54.00

Student 2 year subscription

USD $77.00

2 year subscription

USD $101.00

The problem of motor redundancy has been one of the fundamental, albeit elusive, problems in motor control. Traditionally, it has been viewed as a computational problem for the brain, solved with either optimization methods or by introducing additional constraints to motor tasks. This review suggests that the problem was wrongly formulated, and that the abundant degrees of freedom are not to be eliminated but used to ensure dynamic stability of motor performance, which is vital given the unpredictable intrinsic states and external forces. The idea of synergies as mechanisms ensuring action stability is introduced based on the uncontrolled manifold hypothesis and the theory of control with spatial referent coordinates. The importance of controlled stability is illustrated with the phenomena of anticipatory synergy adjustments. This approach is productive for both basic and applied fields as illustrated, in particular, by changes in motor synergies with neurological disorder and exercise.

Latash is with the Department of Kinesiology, The Pennsylvania State University, University Park, PA.

Address author correspondence to Mark L. Latash at mll11@psu.edu.
Kinesiology Review
Article Sections
References
  • AmbikeS.MattosD.ZatsiorskyV.M. & LatashM.L. (2016). Synergies in the space of control variables within the equilibrium-point hypothesis. Neuroscience 315150161. PubMed doi:10.1016/j.neuroscience.2015.12.012

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ArimotoS.TaharaK.YamaguchiM.NguyenP.T.A. & HanH.Y. (2001). Principles of superposition for controlling pinch motions by means of robot fingers with soft tips. Robotica 192128. doi:10.1017/S0263574700002939

    • Crossref
    • Search Google Scholar
    • Export Citation
  • BabinskiF. (1899). De l’asynergie cerebelleuse. Revue Neurologique 7806816 .

  • BelenkijV.Y.GurfinkelV.S. & Pal’tsevY.I. (1967). Elements of control of voluntary movements. Biofizika 10135141.

  • BernsteinN.A. (1930). A new method of mirror cyclographie and its application towards the study of labor movements during work on a workbench. Hygiene Safety and Pathology of Labor 5 3–9 and 6 3–11 (in Russian).

    • Search Google Scholar
    • Export Citation
  • BernsteinN.A. (1967). The co-ordination and regulation of movements. Oxford, UK: Pergamon Press.

  • BernsteinN.A. (1996). On dexterity and its development. In M.L. Latash & TurveyM.T. (Eds.) Dexterity and its development (pp. 1244). Mahwah, NJ: Erlbaum.

    • Search Google Scholar
    • Export Citation
  • CusumanoJ.P. & CesariP. (2006). Body-goal variability mapping in an aiming task. Biological Cybernetics 94367379. PubMed doi:10.1007/s00422-006-0052-1

    • Crossref
    • Search Google Scholar
    • Export Citation
  • d’AvellaA.SaltielP. & BizziE. (2003). Combinations of muscle synergies in the construction of a natural motor behavior. Nature Neuroscience 6300308. doi:10.1038/nn1010

    • Crossref
    • Search Google Scholar
    • Export Citation
  • DeWaldJ.P.PopeP.S.GivenJ.D.BuchananT.S. & RymerW.Z. (1995). Abnormal muscle coactivation patterns during isometric torque generation at the elbow and shoulder in hemiparetic subjects. Brain 118495510. PubMed doi:10.1093/brain/118.2.495

    • Crossref
    • Search Google Scholar
    • Export Citation
  • DomkinD.LaczkoJ.DjupsjöbackaM.JaricS. & LatashM.L. (2005). Joint angle variability in 3D bimanual pointing: Uncontrolled manifold analysis. Experimental Brain Research 1634457. PubMed doi:10.1007/s00221-004-2137-1

    • Crossref
    • Search Google Scholar
    • Export Citation
  • DomkinD.LaczkoJ.JaricS.JohanssonH. & LatashM.L. (2002). Structure of joint variability in bimanual pointing tasks. Experimental Brain Research 1431123. PubMed doi:10.1007/s00221-001-0944-1

    • Crossref
    • Search Google Scholar
    • Export Citation
  • FalakiA.HuangX.LewisM.M. & LatashM.L. (2017). Motor equivalence and structure of variance: Multi-muscle postural synergies in Parkinson’s disease. Experimental Brain Research 23522432258. PubMed doi:10.1007/s00221-017-4971-y

    • Crossref
    • Search Google Scholar
    • Export Citation
  • FeldmanA.G. (2015). Referent control of action and perception: Challenging conventional theories in behavioral science. New York, NY: Springer.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • GelfandI.M. & LatashM.L. (1998). On the problem of adequate language in movement science. Motor Control 2306313. PubMed doi:10.1123/mcj.2.4.306

    • Crossref
    • Search Google Scholar
    • Export Citation
  • HennemanE.SomjenG. & CarpenterD.O. (1965). Excitability and inhibitibility of motoneurones of different sizes. Journal of Neurophysiology 28599620. PubMed

    • Crossref
    • Search Google Scholar
    • Export Citation
  • HoehnM.YahrM. (1967). Parkinsonism: Onset, progression and mortality. Neurology 17427427. PubMed doi:10.1212/WNL.17.5.427

  • Hughlings JacksonJ. (1889August 17). On the comparative study of disease of the nervous system. British Medical Journal 2355362. doi:10.1136/bmj.2.1494.355

    • Search Google Scholar
    • Export Citation
  • JerdeT.E.SoechtingJ.F. & FlandersM. (2003). Coarticulation in fluent fingerspelling. Journal of Neuroscience 2323832393. PubMed

    • Crossref
    • Search Google Scholar
    • Export Citation
  • JoH.J.LucassenE.HuangX. & LatashM.L. (2017). Changes in multi-digit synergies and their feed-forward adjustments in multiple sclerosis. Journal of Motor Behavior 49218228. PubMed doi:10.1080/00222895.2016.1169986

    • Crossref
    • Search Google Scholar
    • Export Citation
  • JoH.J.MaenzaC.GoodD.C.HuangX.ParkJ.SainburgR.L. & LatashM.L. (2016). Effects of unilateral stroke on multi-finger synergies and their feed-forward adjustments. Neuroscience 319194205. PubMed doi:10.1016/j.neuroscience.2016.01.054

    • Crossref
    • Search Google Scholar
    • Export Citation
  • KelsoJ.A.S. (1995). Dynamic patterns: The self-organization of brain and behavior. Cambridge, UK: MIT Press.

  • KlousM.Danna-dos-SantosA. & LatashM.L. (2010). Multi-muscle synergies in a dual postural task: Evidence for the principle of superposition. Experimental Brain Research 202457471. PubMed doi:10.1007/s00221-009-2153-2

    • Crossref
    • Search Google Scholar
    • Export Citation
  • KrishnamoorthyV.GoodmanS.R.LatashM.L. & ZatsiorskyV.M. (2003). Muscle synergies during shifts of the center of pressure by standing persons: Identification of muscle modes. Biological Cybernetics 89152161. PubMed doi:10.1007/s00422-003-0419-5

    • Crossref
    • Search Google Scholar
    • Export Citation
  • KuglerP.N. & TurveyM.T. (1987). Information natural law and the self-assembly of rhythmic movement. Hillsdale, NJ: Erlbaum.

  • LatashM.L. (2008). Synergy. New York, NY: Oxford University Press

  • LatashM.L. (2012). The bliss (not the problem) of motor abundance (not redundancy). Experimental Brain Research 21715. PubMed doi:10.1007/s00221-012-3000-4

    • Crossref
    • Search Google Scholar
    • Export Citation
  • LatashM.L. (2016). Towards physics of neural processes and behavior. Neuroscience and Biobehavioral Reviews 69136146. PubMed doi:10.1016/j.neubiorev.2016.08.005

    • Crossref
    • Search Google Scholar
    • Export Citation
  • LatashM.L.HuangX. (2015). Neural control of movement stability: Lessons from studies of neurological patients. Neuroscience 3013948. PubMed doi:10.1016/j.neuroscience.2015.05.075

    • Crossref
    • Search Google Scholar
    • Export Citation
  • LatashM.L.ScholzJ.P. & SchönerG. (2007). Toward a new theory of motor synergies. Motor Control 11276308. PubMed doi:10.1123/mcj.11.3.276

    • Crossref
    • Search Google Scholar
    • Export Citation
  • LatashM.L.ShimJ.K.SmilgaA.V. & ZatsiorskyV.M. (2005). A central back-coupling hypothesis on the organization of motor synergies: A physical metaphor and a neural model. Biological Cybernetics 92186191 PubMed doi:10.1007/s00422-005-0548-0

    • Crossref
    • Search Google Scholar
    • Export Citation
  • LatashM.L. & ZatsiorskyV.M. (2016). Biomechanics and motor control: Defining central concepts. New York, NY: Academic Press

  • LewisM.M.LeeE.-Y.JoH.J.ParkJ.LatashM.L. & HuangX. (2016). Synergy as a new and sensitive marker of basal ganglia dysfunction: A study of asymptomatic welders. Neurotoxicology 567685. PubMed doi:10.1016/j.neuro.2016.06.016

    • Crossref
    • Search Google Scholar
    • Export Citation
  • MartinV.ScholzJ.P. & SchönerG. (2009). Redundancy, self-motion, and motor control. Neural Computation 2113711414. PubMed doi:10.1162/neco.2008.01-08-698

    • Crossref
    • Search Google Scholar
    • Export Citation
  • MattosD.LatashM.L.ParkE.KuhlJ. & ScholzJ.P. (2011). Unpredictable elbow joint perturbation during reaching results in multijoint motor equivalence. Journal of Neurophysiology 10614241436. PubMed doi:10.1152/jn.00163.2011

    • Crossref
    • Search Google Scholar
    • Export Citation
  • MüllerH. & SternadD. (2003). A randomization method for the calculation of covariation in multiple nonlinear relations: Illustrated with the example of goal-directed movements. Biological Cybernetics 892233.

    • Search Google Scholar
    • Export Citation
  • OlafsdottirH.YoshidaN.ZatsiorskyV.M.LatashM.L. (2005). Anticipatory covariation of finger forces during self-paced and reaction time force production. Neuroscience Letters 3819296. PubMed doi:10.1016/j.neulet.2005.02.003

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ParkJ.WuY.-H.LewisM.M.HuangX. & LatashM.L. (2012). Changes in multi-finger interaction and coordination in Parkinson’s disease. Journal of Neurophysiology 108915924. PubMed doi:10.1152/jn.00043.2012

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ParkJ. & XuD. (2017). Multi-finger interaction and synergies in finger flexion and extension force production. Frontiers in Human Neuroscience 11318. PubMed doi:10.3389/fnhum.2017.00318

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ReismanD. & ScholzJ.P. (2003). Aspects of joint coordination are preserved during pointing in persons with post-stroke hemiparesis. Brain 12625102527. PubMed doi:10.1093/brain/awg246

    • Crossref
    • Search Google Scholar
    • Export Citation
  • SainburgR.L. (2005). Handedness: Differential specializations for control of trajectory and position. Exercise and Sport Science Reviews 33206213. doi:10.1097/00003677-200510000-00010

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ScholzJ.P.KangN.PattersonD. & LatashM.L. (2003). Uncontrolled manifold analysis of single trials during multi-finger force production by persons with and without Down syndrome. Experimental Brain Research 1534558. PubMed doi:10.1007/s00221-003-1580-8

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ScholzJ.P. & SchönerG. (1999). The uncontrolled manifold concept: Identifying control variables for a functional task. Experimental Brain Research 126289306. PubMed doi:10.1007/s002210050738

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ScholzJ.P.SchönerG.HsuW.L.JekaJ.J.HorakF.MartinV. (2007). Motor equivalent control of the center of mass in response to support surface perturbations. Experimental Brain Research 180163179. PubMed doi:10.1007/s00221-006-0848-1

    • Crossref
    • Search Google Scholar
    • Export Citation
  • SchönerG. (1995). Recent developments and problems in human movement science and their conceptual implications. Ecological Psychology 7291314. doi:10.1207/s15326969eco0704_5

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ShadmehrR. & WiseS.P. (2005). The computational neurobiology of reaching and pointing. Cambridge, MA: MIT Press.

  • ShimJ.K.LayB.ZatsiorskyV.M. & LatashM.L. (2004). Age-related changes in finger coordination in static prehension tasks. Journal of Applied Physiology 97213224. PubMed doi:10.1152/japplphysiol.00045.2004

    • Crossref
    • Search Google Scholar
    • Export Citation
  • TingL.H. & MacphersonJ.M. (2005). A limited set of muscle synergies for force control during a postural task. Journal of Neurophysiology 93609613. PubMed doi:10.1152/jn.00681.2004

    • Crossref
    • Search Google Scholar
    • Export Citation
  • TreschM.C.CheungV.C.d’AvellaA. (2006). Matrix factorization algorithms for the identification of muscle synergies: Evaluation on simulated and experimental data sets. Journal of Neurophysiology 9521992212.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • VaillancourtD. & NewellK.M. (2002). Changing complexity in human behavior and physiology through aging and disease. Neurobiology of Aging 23111. PubMed doi:10.1016/S0197-4580(01)00247-0

    • Crossref
    • Search Google Scholar
    • Export Citation
  • WilhelmL.ZatsiorskyV.M. & LatashM.L. (2013). Equifinality and its violations in a redundant system: Multi-finger accurate force production. Journal of Neurophysiology 11019651973. PubMed doi:10.1152/jn.00461.2013

    • Crossref
    • Search Google Scholar
    • Export Citation
  • WolpertD.M.MiallR.C. & KawatoM. (1998). Internal models in the cerebellum. Trends in Cognitive Science 2338347. doi:10.1016/S1364-6613(98)01221-2

    • Crossref
    • Search Google Scholar
    • Export Citation
  • WuY.-H. & LatashM.L. (2014). The effects of practice on coordination. Exercise and Sport Science Reviews 423742. doi:10.1249/JES.0000000000000002

    • Crossref
    • Search Google Scholar
    • Export Citation
  • WuY.-H.PazinN.ZatsiorskyV.M. & LatashM.L. (2012). Practicing elements vs. practicing coordination: Changes in the structure of variance. Journal of Motor Behavior 44471478. PubMed doi:10.1080/00222895.2012.740101

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ZatsiorskyV.M.LatashM.L.GaoF. & ShimJ.K. (2004). The principle of superposition in human prehension. Robotica 22231234. PubMed doi:10.1017/S0263574703005344

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ZhangW.SainburgR.L.ZatsiorskyV.M. & LatashM.L. (2006). Hand dominance and multi-finger synergies. Neuroscience Letters 409200204. PubMed doi:10.1016/j.neulet.2006.09.048

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ZhangW.ScholzJ.P.ZatsiorskyV.M. & LatashM.L. (2008). What do synergies do? Effects of secondary constraints on multi-digit synergies in accurate force-production tasks. Journal of Neurophysiology 99500513. PubMed doi:10.1152/jn.01029.2007

    • Crossref
    • Search Google Scholar
    • Export Citation
  • ZhouT.ZhangL. & LatashM.L. (2015). Intentional and unintentional multi-joint movements: Their nature and structure of variance. Neuroscience 289181193. PubMed doi:10.1016/j.neuroscience.2014.12.079

    • Crossref
    • Search Google Scholar
    • Export Citation
Article Metrics
All Time Past Year Past 30 Days
Abstract Views 45 45 12
Full Text Views 1 1 0
PDF Downloads 1 1 0
Altmetric Badge
PubMed
Google Scholar