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Neuroplasticity of imagined wrist actions after spinal cord injury: a pilot study

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Abstract

Motor imagery (MI - i.e., the mental representation of an action without physically executing it) stimulates brain motor networks and promotes motor learning after spinal cord injury (SCI). An interesting issue is whether the brain networks controlling MI are being reorganized with reference to spared motor functions. In this pilot study, we tested using magnetoencephalography (MEG) whether changes in cortical recruitment during MI were related to the motor changes elicited by rehabilitation. Over a 1-year period of inclusion, C6 SCI participants (n = 4) met stringent criteria for inclusion in a rehabilitation program focused on the tenodesis prehension (i.e., a compensatory prehension enabling seizing of objects in spite of hand and forearm muscles paralysis). After an extended baseline period of 5 weeks including repeated MEG and chronometric assessments of motor performance, MI training was embedded to the classical course of physiotherapy for five additional weeks. Posttest MEG and motor performance data were collected. A group of matched healthy control participants underwent a similar procedure. The MI intervention resulted in changes in the variability of the wrist extensions, i.e., a key movement of the tenodesis grasp (p < .05). Interestingly, the extent of cortical recruitment, quantified by the number of MEG activation sources recorded within Brodmann areas 1–8 during MI of the wrist extension, significantly predicted actual movement variability changes across sessions (p < .001). However, no such relationship was present for movement times. Repeated measurements afforded a reliable statistical power (range .70–.97). This pilot study does not provide straightforward evidence of MI efficacy, which would require a randomized controlled trial. Nonetheless, the data showed that the relationship between action and imagery of spared actions may be preserved after SCI.

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Notes

  1. For a figure of raw MEG and motor performance data plotted as in Fig. 5, see supplementary material 3.

  2. Hence, including a group healthy participants performing MI represents further development of the present design.

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Acknowledgments

This research was supported by Grant from Hospital Clinical Research Program (PHRC) 2010-541/142. We gratefully acknowledge CC-IN2P3 through TIDRA (http://www.tidra.org) for providing a significant amount of computing resources and services needed for this work.

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The authors declare no conflict of interest.

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Authors and Affiliations

  1. Centre de Recherche et d’Innovation sur le Sport (EA 647), Université de Lyon, Université Claude Bernard Lyon 1, 27-29 Boulevard du 11 Novembre 1918, 69622, Villeurbanne Cedex, France

    Franck Di Rienzo, Aymeric Guillot, Sébastien Mateo & Christian Collet

  2. Hôpital Henri Gabrielle, Hospices Civils de Lyon, 69230, Saint Genis-Laval, France

    Sébastien Mateo & Gilles Rode

  3. Département MEG, CERMEP imagerie du vivant, 69677, Bron, France

    Sébastien Mateo, Sébastien Daligault & Claude Delpuech

  4. INSERM U1028, CNRS UMR5292, Centre des neurosciences de Lyon, 69000, Lyon, France

    Gilles Rode

  5. Institut Universitaire de France, 75000, Paris, France

    Aymeric Guillot

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  1. Franck Di Rienzo
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  2. Aymeric Guillot
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Correspondence to Franck Di Rienzo.

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Di Rienzo, F., Guillot, A., Mateo, S. et al. Neuroplasticity of imagined wrist actions after spinal cord injury: a pilot study. Exp Brain Res 233, 291–302 (2015). https://doi.org/10.1007/s00221-014-4114-7

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