Experimental Brain Research

, Volume 173, Issue 4, pp 689–697 | Cite as

Are there distinct neural representations of object and limb dynamics?

Research Article


In recent studies of human motor learning, subjects learned to move the arm while grasping a robotic device that applied novel patterns of forces to the hand. Here, we examined the generality of force field learning. We tested the idea that contextual cues associated with grasping a novel object promote the acquisition and use of a distinct internal model, associated with that object. Subjects learned to produce point-to-point arm movements to targets in a horizontal plane while grasping a robotic linkage that applied either a velocity-dependent counter-clockwise or clockwise force field to the hand. Following adaptation, subjects let go of the robot and were asked to generate the same movements in free space. Small but reliable after-effects were observed during the first eight movements in free space, however, these after-effects were significantly smaller than those observed for control subjects who moved the robot in a null field. No reduction in retention was observed when subjects subsequently returned to the force field after moving in free space. In contrast, controls who reached with the robot in a NF showed much poorer retention when returning to a force field. These findings are consistent with the idea that contextual cues associated with grasping a novel object may promote the acquisition of a distinct internal model of the dynamics of the object, separate from internal models used to control limb dynamics alone.


Human motor learning Multi-joint arm movement Internal model Force field adaptation Limb dynamics 



The authors wish to thank N. Malfait, A. Mattar and D. Ostry for helpful comments. This Research was supported by CIHR (Canada).


  1. Bays PM, Flanagan JR, Wolpert DM (2005) Interference between velocity-dependent and position-dependent force-fields indicates that tasks depending on different kinematic parameters compete for motor working memory. Exp Brain Res 163:400–405CrossRefPubMedGoogle Scholar
  2. Conditt MA, Mussa-Ivaldi FA (1999) Central representation of time during motor learning. Proc Natl Acad Sci USA 96:11625–11630CrossRefPubMedGoogle Scholar
  3. Conditt MA, Gandolfo F, Mussa-Ivaldi FA (1997) The motor system does not learn the dynamics of the arm by rote memorization of past experience. J Neurophysiol 78:554–560PubMedGoogle Scholar
  4. Davidson PR, Wolpert DM (2004) Internal models underlying grasp can be additively combined. Exp Brain Res 155:334–340CrossRefPubMedGoogle Scholar
  5. Davidson PR, Wolpert DM, Scott SH, Flanagan JR (2005) Common encoding of novel dynamic loads applied to the hand and arm. J Neurosci 25:5425–5429CrossRefPubMedGoogle Scholar
  6. Debicki DB, Gribble PL (2004) Inter-joint coupling strategy during adaptation to novel viscous loads in human arm movement. J Neurophysiol 92:754–765CrossRefPubMedGoogle Scholar
  7. Debicki DB, Gribble PL (2005) Persistence of inter-joint coupling during single-joint elbow flexions after shoulder fixation. Exp Brain Res 163:252–257CrossRefPubMedGoogle Scholar
  8. Flanagan JR, Wing AM (1997) The role of internal models in motion planning and control: evidence from grip force adjustments during movements of hand-held loads. J Neurosci 17:1519–1528PubMedGoogle Scholar
  9. Gandolfo F, Mussa-Ivaldi FA, Bizzi E (1996) Motor learning by field approximation. Proc Natl Acad Sci USA 93:3843–3846CrossRefPubMedGoogle Scholar
  10. Gandolfo F, Li C, Benda BJ, Schioppa CP, Bizzi E (2000) Cortical correlates of learning in monkeys adapting to a new dynamical environment. Proc Natl Acad Sci USA 97:2259–2263CrossRefPubMedGoogle Scholar
  11. Gribble PL, Scott SH (2002) Overlap of internal models in motor cortex for mechanical loads during reaching. Nature 417:938–941CrossRefPubMedGoogle Scholar
  12. Haruno M, Wolpert DM, Kawato M (2001) Mosaic model for sensorimotor learning and control. Neural Comput 13:2201–2220CrossRefPubMedGoogle Scholar
  13. Karniel A, Mussa-Ivaldi FA (2002) Does the motor control system use multiple models and context switching to cope with a variable environment? Exp Brain Res 143:520–524CrossRefPubMedGoogle Scholar
  14. Kawato M (1999) Internal models for motor control and trajectory planning. Curr Opin Neurobiol 9:718–727CrossRefPubMedGoogle Scholar
  15. Koshland GF, Galloway JC, Nevoret-Bell CJ (2000) Control of the wrist in three-joint arm movements to multiple directions in the horizontal plane. J Neurophysiol 83:3188–3195PubMedGoogle Scholar
  16. Krouchev NI, Kalaska JF (2003) Context-dependent anticipation of different task dynamics: rapid recall of appropriate motor skills using visual cues. J Neurophysiol 89:1165–1175PubMedCrossRefGoogle Scholar
  17. Lackner JR, Dizio P (1994) Rapid adaptation to Coriolis force perturbations of arm trajectory. J Neurophysiol 72:299–313PubMedGoogle Scholar
  18. Malfait N, Gribble PL, Ostry DJ (2005) Generalization of motor learning based on multiple field exposures and local adaptation. J Neurophysiol 93:3327–3338CrossRefPubMedGoogle Scholar
  19. Mattar AA, Gribble PL (2005) Motor learning by observing. Neuron 46:153–160CrossRefPubMedGoogle Scholar
  20. Mattar AAG, Ostry DJ (2005) Motor learning as a running average of past experience. In: Society for Neuroscience Abstracts Program No. 181.5. Society for Neuroscience, Washington, DCGoogle Scholar
  21. Osu R, Hirai S, Yoshioka T, Kawato M (2004) Random presentation enables subjects to adapt to two opposing forces on the hand. Nat Neurosci 7:111–112CrossRefPubMedGoogle Scholar
  22. Sainburg RL, Ghez C, Kalakanis D (1999) Intersegmental dynamics are controlled by sequential anticipatory, error correction, and postural mechanisms. J Neurophysiol 81:1045–1056PubMedGoogle Scholar
  23. Shadmehr R, Brashers-Krug T (1997) Functional stages in the formation of human long-term motor memory. J Neurosci 17:409–419PubMedGoogle Scholar
  24. Shadmehr R, Mussa-Ivaldi FA (1994) Adaptive representation of dynamics during learning of a motor task. J Neurosci 14:3208–3224PubMedGoogle Scholar
  25. Shadmehr R, Brandt J, Corkin S (1998) Time-dependent motor memory processes in amnesic subjects. J Neurophysiol 80:1590–1597PubMedGoogle Scholar
  26. Thoroughman KA, Shadmehr R (1999) Electromyographic correlates of learning an internal model of reaching movements. J Neurosci 19:8573–8588PubMedGoogle Scholar
  27. Wolpert DM, Flanagan JR (2001) Motor prediction. Curr Biol 11:R729–R732CrossRefPubMedGoogle Scholar

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Department of PsychologyThe University of Western OntarioLondonCanada
  2. 2.Graduate Program in NeuroscienceThe University of Western OntarioLondonCanada
  3. 3.Department of Physiology and PharmacologyThe University of Western OntarioLondonCanada
  4. 4.CIHR Group in Action and PerceptionThe University of Western OntarioLondonCanada

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