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Adaptation reveals independent control networks for human walking


Human walking is remarkably adaptable on short and long timescales. We can immediately transition between directions and gait patterns, and we can adaptively learn accurate calibrations for different walking contexts. Here we studied the degree to which different motor patterns can adapt independently. We used a split-belt treadmill to adapt the right and left legs to different speeds and in different directions (forward versus backward). To our surprise, adults could easily walk with their legs moving in opposite directions. Analysis of aftereffects showed that walking adaptations are stored independently for each leg and do not transfer across directions. Thus, there are separate functional networks controlling forward and backward walking in humans, and the circuits controlling the right and left legs can be trained individually. Such training could provide a new therapeutic approach for correcting various walking asymmetries.

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Figure 1: Experimental setup and phase analysis.
Figure 2: Adaptation does not transfer between forward and backward walking.
Figure 3: Dual storage of forward and backward aftereffects.
Figure 4: Adaptation induces individual leg effects.
Figure 5: A schematic model of leg-specific adaptation.
Figure 6: Sketch of proposed organization of adaptable locomotor networks in human.

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  1. Lam, T., Anderschitz, M. & Dietz, V. Contribution of feedback and feedforward strategies to locomotor adaptations. J. Neurophysiol. 95, 766–773 (2006).

    Article  Google Scholar 

  2. Pearson, K.G. Neural adaptation in the generation of rhythmic behavior. Annu. Rev. Physiol. 62, 723–753 (2000).

    Article  CAS  Google Scholar 

  3. Reisman, D.S., Block, H.J. & Bastian, A.J. Interlimb coordination during locomotion: what can be adapted and stored? J. Neurophysiol. 94, 2403–2415 (2005).

    Article  Google Scholar 

  4. Morton, S.M. & Bastian, A.J. Cerebellar contributions to locomotor adaptations during splitbelt treadmill walking. J. Neurosci. 26, 9107–9116 (2006).

    Article  CAS  Google Scholar 

  5. Reisman, D.S., Wityk, R., Silver, K. & Bastian, A.J. Locomotor adaptation on a split-belt treadmill can improve walking symmetry post-stroke. Brain, published online 2 April 2007 (doi:10.1093/brain/awm035).

    Article  Google Scholar 

  6. Grillner, S. & Zangger, P. On the central generation of locomotion in the low spinal cat. Exp. Brain Res. 34, 241–261 (1979).

    Article  CAS  Google Scholar 

  7. Mortin, L.I. & Stein, P.S. Spinal cord segments containing key elements of the central pattern generators for three forms of scratch reflex in the turtle. J. Neurosci. 9, 2285–2296 (1989).

    Article  CAS  Google Scholar 

  8. Calancie, B. et al. Involuntary stepping after chronic spinal cord injury. Evidence for a central rhythm generator for locomotion in man. Brain 117, 1143–1159 (1994).

    Article  Google Scholar 

  9. Dimitrijevic, M.R., Gerasimenko, Y. & Pinter, M.M. Evidence for a spinal central pattern generator in humans. Ann. NY Acad. Sci. 860, 360–376 (1998).

    Article  CAS  Google Scholar 

  10. Grasso, R., Bianchi, L. & Lacquaniti, F. Motor patterns for human gait: backward versus forward locomotion. J. Neurophysiol. 80, 1868–1885 (1998).

    Article  CAS  Google Scholar 

  11. Lafreniere-Roula, M. & McCrea, D.A. Deletions of rhythmic motoneuron activity during fictive locomotion and scratch provide clues to the organization of the mammalian central pattern generator. J. Neurophysiol. 94, 1120–1132 (2005).

    Article  Google Scholar 

  12. Rybak, I.A., Shevtsova, N.A., Lafreniere-Roula, M. & McCrea, D.A. Modelling spinal circuitry involved in locomotor pattern generation: insights from deletions during fictive locomotion. J. Physiol. (Lond.) 577, 617–639 (2006).

    Article  CAS  Google Scholar 

  13. Lamb, T. & Yang, J.F. Could different directions of infant stepping be controlled by the same locomotor central pattern generator? J. Neurophysiol. 83, 2814–2824 (2000).

    Article  CAS  Google Scholar 

  14. Yang, J.F., Lamont, E.V. & Pang, M.Y. Split-belt treadmill stepping in infants suggests autonomous pattern generators for the left and right leg in humans. J. Neurosci. 25, 6869–6876 (2005).

    Article  CAS  Google Scholar 

  15. Dietz, V., Zijlstra, W. & Duysens, J. Human neuronal interlimb coordination during split-belt locomotion. Exp. Brain Res. 101, 513–520 (1994).

    Article  CAS  Google Scholar 

  16. Kiehn, O. Locomotor circuits in the mammalian spinal cord. Annu. Rev. Neurosci. 29, 279–306 (2006).

    Article  CAS  Google Scholar 

  17. Hammar, I., Bannatyne, B.A., Maxwell, D.J., Edgley, S.A. & Jankowska, E. The actions of monoamines and distribution of noradrenergic and serotoninergic contacts on different subpopulations of commissural interneurons in the cat spinal cord. Eur. J. Neurosci. 19, 1305–1316 (2004).

    Article  Google Scholar 

  18. Morton, S.M. & Bastian, A.J. Prism adaptation during walking generalizes to reaching and requires the cerebellum. J. Neurophysiol. 92, 2497–2509 (2004).

    Article  Google Scholar 

  19. Krakauer, J.W., Mazzoni, P., Ghazizadeh, A., Ravindran, R. & Shadmehr, R. Generalization of motor learning depends on the history of prior action. PLoS Biol. 4, e316 (2006).

    Article  Google Scholar 

  20. Reynolds, R.F. & Bronstein, A.M. The moving platform aftereffect: limited generalization of a locomotor adaptation. J. Neurophysiol. 91, 92–100 (2004).

    Article  CAS  Google Scholar 

  21. Yanagihara, D. & Kondo, I. Nitric oxide plays a key role in adaptive control of locomotion in cat. Proc. Natl. Acad. Sci. USA 93, 13292–13297 (1996).

    Article  CAS  Google Scholar 

  22. Horak, F.B. & Diener, H.C. Cerebellar control of postural scaling and central set in stance. J. Neurophysiol. 72, 479–493 (1994).

    Article  CAS  Google Scholar 

  23. Lang, C.E. & Bastian, A.J. Cerebellar subjects show impaired adaptation of anticipatory EMG during catching. J. Neurophysiol. 82, 2108–2119 (1999).

    Article  CAS  Google Scholar 

  24. Smith, M.A. & Shadmehr, R. Intact ability to learn internal models of arm dynamics in Huntington's disease but not cerebellar degeneration. J. Neurophysiol. 93, 2809–2821 (2005).

    Article  Google Scholar 

  25. Bastian, A.J. Learning to predict the future: the cerebellum adapts feedforward movement control. Curr. Opin. Neurobiol. 16, 645–649 (2006).

    Article  CAS  Google Scholar 

  26. Bosco, G., Poppele, R.E. & Eian, J. Reference frames for spinal proprioception: limb-endpoint based or joint-level based? J. Neurophysiol. 83, 2931–2945 (2000).

    Article  CAS  Google Scholar 

  27. Bosco, G., Eian, J. & Poppele, R.E. Kinematic and nonkinematic signals transmitted to the cat cerebellum during passive treadmill stepping. Exp. Brain Res. 167, 394–403 (2005).

    Article  CAS  Google Scholar 

  28. Bosco, G., Eian, J. & Poppele, R.E. Phase-specific sensory representations in spinocerebellar activity during stepping: evidence for a hybrid kinematic/kinetic framework. Exp. Brain Res. 175, 83–96 (2006).

    Article  CAS  Google Scholar 

  29. Poppele, R.E., Rankin, A. & Eian, J. Dorsal spinocerebellar tract neurons respond to contralateral limb stepping. Exp. Brain Res. 149, 361–370 (2003).

    Article  CAS  Google Scholar 

  30. Arshavsky, Y.I., Gelfand, I.M., Orlovsky, G.N. & Pavlova, G.A. Messages conveyed by spinocerebellar pathways during scratching in the cat. II. Activity of neurons of the ventral spinocerebellar tract. Brain Res. 151, 493–506 (1978).

    Article  CAS  Google Scholar 

  31. Orlovsky, G.N. The effect of different descending systems on flexor and extensor activity during locomotion. Brain Res. 40, 359–371 (1972).

    Article  CAS  Google Scholar 

  32. Orlovsky, G.N. Activity of vestibulospinal neurons during locomotion. Brain Res. 46, 85–98 (1972).

    Article  CAS  Google Scholar 

  33. Yang, J.F. et al. Infant stepping: a window to the behaviour of the human pattern generator for walking. Can. J. Physiol. Pharmacol. 82, 662–674 (2004).

    Article  CAS  Google Scholar 

  34. Forssberg, H., Grillner, S., Halbertsma, J. & Rossignol, S. The locomotion of the low spinal cat. II. Interlimb coordination. Acta Physiol. Scand. 108, 283–295 (1980).

    Article  CAS  Google Scholar 

  35. Berkowitz, A. & Stein, P.S. Activity of descending propriospinal axons in the turtle hindlimb enlargement during two forms of fictive scratching: phase analyses. J. Neurosci. 14, 5105–5119 (1994).

    Article  CAS  Google Scholar 

  36. Kullander, K. et al. Role of EphA4 and EphrinB3 in local neuronal circuits that control walking. Science 299, 1889–1892 (2003).

    Article  CAS  Google Scholar 

  37. Batschelet, E. Circular Statistics in Biology (Academic Press, New York, 1981).

    Google Scholar 

  38. Zar, J.H. Biostatistical Analysis (Prentice Hall, Upper Saddle River, New Jersey, 1999).

    Google Scholar 

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Thanks to D. Reisman, S. Morton, J. Bastian and E. Connor for thoughtful discussions and input about these studies, and to A. Torrie for help with testing. This work was supported by US National Institutes of Health R01HD048740 and C06RR15488.

Author information

Authors and Affiliations



J.T.C. and A.J.B. designed the experiments and cowrote the manuscript. J.T.C. conducted the experiments and data analyses.

Corresponding authors

Correspondence to Julia T Choi or Amy J Bastian.

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The authors declare no competing financial interests.

Supplementary information

Supplementary Video 1

Animation of experiment I: test of transfer from forward to backward walking. (MOV 1208 kb)

Supplementary Video 2

Animation of experiment II: test of transfer from backward to forward walking. (MOV 1344 kb)

Supplementary Video 3

Animation of experiment III: test of dual adaptation in backward and forward walking. (MOV 1919 kb)

Supplementary Video 4

Animation of hybrid adaptation: hybrid-walking adaptation. (MOV 819 kb)

Supplementary Video 5

Animation of experiment IV: test of transfer from hybrid walking to forward and backward walking. (MOV 1843 kb)

Supplementary Data (PDF 230 kb)

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Choi, J., Bastian, A. Adaptation reveals independent control networks for human walking. Nat Neurosci 10, 1055–1062 (2007).

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