Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Perceptual basis of bimanual coordination


Periodic bimanual movements are often the focus of studies of the basic organizational principles of human actions1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25. In such movements there is a typical spontaneous tendency towards mirror symmetry. Even involuntary slips from asymmetrical movement patterns into symmetry occur, but not vice versa. Traditionally, this phenomenon has been interpreted as a tendency towards co-activation of homologous muscles, probably originating in motoric neuronal structures. Here we provide evidence contrary to this widespread assumption. We show for two prominent experimental models—bimanual finger oscillation1 and bimanual four-finger tapping2—that the symmetry bias is actually towards spatial, perceptual symmetry, without regard to the muscles involved. We suggest that spontaneous coordination phenomena of this kind are purely perceptual in nature. In the case of a bimanual circling model, our findings reveal that highly complex, even ‘impossible’ movements can easily be performed with only simple visual feedback. A ‘motoric’ representation of the performed perceptual oscillation patterns is not necessary. Thus there is no need to translate such a ‘motoric’ into a ‘perceptual’ representation or vice versa, using ‘internal models’ (ref. 29). We suggest that voluntary movements are organized by way of a representation of the perceptual goals, whereas the corresponding motor activity, of sometimes high complexity, is spontaneously and flexibly tuned in.

This is a preview of subscription content

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Instructed, synchronous finger oscillation patterns and hand positions.
Figure 2: Relative phase of the fingertips averaged across subjects in experiment 1. a, Congruous hand positions and symmetrical movement instruction.
Figure 3: Percentage of symmetrical taps, in experiment 2, split by movement instruction and bimanual finger setting (see text).
Figure 4: Apparatus used in experiment 3, and instructed synchronous circling patterns of the flags.
Figure 5: Histograms of relative angle of the circling flags, averaged across subjects in experiment 3.


  1. Kelso, J. A. S. Phase transitions and critical behavior in human bimanual coordination. Am. J. Physiol. Regul. 15, R1000–R1004 (1984).

    ADS  Google Scholar 

  2. Kelso, J. A. S. Dynamic patterns: The Self-organization of Brain and Behavior (MIT Press, Cambridge, Massachusetts, 1995).

    Google Scholar 

  3. Johnson, K. A. et al. Bimanual co-ordination in Parkinson's disease. Brain 121, 743–753 (1998).

    Article  Google Scholar 

  4. Kelso, J. A. S. The informational character of self-organized coordination dynamics. Hum. Mov. Sci. 13, 393–413 (1994).

    Article  Google Scholar 

  5. Swinnen, P. S., Jardin, K., Meulenbroek, R., Dounskaia, N. & Hofkens-Van Den Brandt, M. Egocentric and allocentric constraints in the expression of patterns of interlimb coordination. J. Cogn. Neurosci. 9, 348–377 (1997).

    CAS  Article  Google Scholar 

  6. Swinnen, P. S. et al. Exploring interlimb constraints during bimanual graphic performance: effects of muscle grouping and direction. Behav. Brain Res. 90, 79–87 (1998).

    CAS  Article  Google Scholar 

  7. Buchanan, J. J. & Kelso, J. A. S. Posturally induced transitions in rhythmic multijoint limb movements. Exp. Brain Res. 94, 131–142 (1993).

    CAS  Article  Google Scholar 

  8. Kelso, J. A. S., Fink, P. W., DeLaplain, C. R. & Carson, R. G. Haptic information stabilizes and destabilizes coordination dynamics. Proc. R. Soc. Lond. B 268, 1207–1213 (2001).

    CAS  Article  Google Scholar 

  9. Haken, H., Kelso, J. A. S. & Bunz, H. A theoretical model of phase transitions in human hand movements. Biol. Cybern. 51, 347–356 (1985).

    MathSciNet  CAS  Article  Google Scholar 

  10. Haken, H. Principles of Brain Functioning (Springer, Berlin, 1996).

    Book  Google Scholar 

  11. Lee, T. D., Blandin, Y. & Proteau, L. Effects of task instructions and oscillation freqency on bimanual coordination. Psychol. Res. 59, 100–106 (1996).

    CAS  Article  Google Scholar 

  12. Baldissera, F., Cavallari, P. & Civaschi, P. Preferential coupling between voluntary movements of ipsilateral limbs. Neurosci. Lett. 34, 95–100 (1982).

    CAS  Article  Google Scholar 

  13. Kelso, J. A. S., Buchanan, J. J. & Wallace, S. A. Order parameters for the neural organization of single, multijoint limb movement patterns. Exp. Brain Res. 85, 432–444 (1991).

    CAS  Article  Google Scholar 

  14. Riek, S., Carson, R. G. & Byblow, W. D. Spatial and muscular dependencies in bimanual coordination. J. Hum. Mov. Stud. 23, 251–265 (1992).

    Google Scholar 

  15. Scholz, J. P. & Kelso, J. A. S. A quantitative approach to understanding the formation and change of coordinated movement patterns. J. Mot. Behav. 21, 122–144 (1989).

    CAS  Article  Google Scholar 

  16. Carson, R. G. The dynamics of isometric bimanual coordination. Exp. Brain Res. 105, 465–476 (1995).

    CAS  PubMed  Google Scholar 

  17. Cattaert, D., Semjen, A. & Summers, J. J. Simulating a neural cross-talk model for between-hand interference during bimanual circle drawing. Biol. Cybern. 81, 343–358 (1999).

    CAS  Article  Google Scholar 

  18. Heuer, H. Structural constraints on bimanual movements. Psychol. Res. 55, 83–98 (1993).

    CAS  Article  Google Scholar 

  19. Semjen, A., Summers, J. J. & Cattaert, D. The coordination of the hands in bimanual circle drawing. J. Exp. Psychol. Hum. Percept. 21, 1139–1157 (1995).

    Article  Google Scholar 

  20. Carson, R. G., Thomas, J., Summers, J. J., Walters, M. R. & Semjen, A. The dynamics of bimanual circle drawing. Q. J. Exp. Psychol. 50A, 664–683 (1997).

    Article  Google Scholar 

  21. Sternad, D. Debates in dynamics: a dynamical systems perspective on action and perception. Hum. Mov. Sci 19, 407–423 (2000).

    Article  Google Scholar 

  22. Riley, M. A. & Turvey, M. T. Dynamics in action: intentional behavior as a complex system. Am. J. Psychol. 114, 160–169 (2001).

    Article  Google Scholar 

  23. Park, H., Collins, D. R. & Turvey, M. T. Dissociation of muscular and spatial constraints on patterns of interlimb coordination. J. Exp. Psychol. Hum. 27, 32–47 (2001).

    CAS  Article  Google Scholar 

  24. Saltzman, E. L. in Mind as Motion. Explorations in the Dynamics of Cognition (eds Port, R. F. & van Gelder, T.) 149–173 (MIT Press, Cambridge, 1995).

    Google Scholar 

  25. Amazeen, P. G., Amazeen, E. L. & Turvey, M. T. Breaking the reflectional symmetry of interlimb coordination dynamics. J. Mot. Behav. 30 (3), 199–216 (1998).

    CAS  Article  Google Scholar 

  26. Zaal, F. T. J. M., Bingham, G. P. & Schmidt, R. C. Visual perception of mean relative phase and phase variability. J. Exp. Psychol. Hum. Percept. 26, 1209–1220 (2000).

    CAS  Article  Google Scholar 

  27. Schmidt, R. A. in Human Motor Behavior: An Introduction (ed. Kelso, J. A. S.) 189–235 (Erlbaum, Hillsdale, New Jersey, 1982).

    Google Scholar 

  28. Jordan, M. I. in The Cognitive Neurosciences (ed. Gazzaniga, M. S.) 597–609 (MIT Press, Cambridge, 1995).

    Google Scholar 

  29. Wolpert, D. M. & Ghahramani, Z. Computational principles of movement neuroscience. Nature Neurosci. (Suppl.) 3, 1212–1217 (2000).

    CAS  Article  Google Scholar 

  30. Prinz, W. Perception and action planning. Europ. J. Cogn. Psychol. 9 (20), 129–154 (1997).

    Article  Google Scholar 

Download references


We wish to thank S. Jordan for discussions; F. Banci for constructing the apparatus used in experiment 3; S. Alessio, B. Schroer and M. Hove for running the experiments; and S. Hass for suggestions concerning the experimental procedure.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Franz Mechsner.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Mechsner, F., Kerzel, D., Knoblich, G. et al. Perceptual basis of bimanual coordination. Nature 414, 69–73 (2001).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing