Effects of spastic cerebral palsy on multi-finger coordination during isometric force production tasks
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In this study, we quantified changes in finger interdependence (enslaving), multi-finger synergies, and feedforward modulation of synergy properties (i.e., anticipatory synergy adjustment) during single- and multi-finger force production tasks in individuals with cerebral palsy (CP). Spastic diplegic CP and healthy control subjects performed sets of finger force production tasks by each of the hands, including maximal force production and submaximal quick pulse force production in an isometric condition. The framework of the uncontrolled manifold hypothesis was used to quantify the indices of multi-finger synergies and the anticipatory synergy adjustment (ASA). The CP group showed lower maximal forces and higher indices of finger interdependence (enslaving), while the indices of multi-finger synergies stabilizing total finger forces during stable force production were not different significantly compared to the controls. Further, the time of ASA for the CP group was not delayed. The CP group showed a significantly less drop in the synergy indices during the anticipatory and quick pulse phase compared to the control group, which was accompanied by larger co-contraction indices of the forearm muscles. These findings suggest that the function of assembling motor synergies for stable force production is not affected by CP, while the ability to modulate synergy properties may be impaired with CP partially due to spasticity. The spasticity presumably hampers the purposeful feedforward destabilization of the performance. The results suggest that quantification of multi-digit synergies may provide an alternative tool for quantitative assessment of impaired coordination in the CP individuals.
KeywordsCerebral palsy Multi-finger synergy Anticipatory synergy adjustment Stability
This work was supported in part by the Ministry of Education of the Republic of Korea and the National Research Foundation of Korea (NRF-2016S1A5A8020309), the Creative-Pioneering Researchers Program through Seoul National University (SNU), and the Nano Material Technology Development Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT and Future Planning (no. 2016M3A7B4910).
- Bansal R, Agarwal A, Sharma M (2016) Hand preference in cerebral palsy with special reference to prematurity. Int J Sci Study 4(1):288–291. https://doi.org/10.1186/s12891-018-2003-010.17354/ijss/2016/235 CrossRefGoogle Scholar
- Brown JK, van Rensburg F, Walsh G, Lakie M, Wright GW (1987) A neurological study of hand function of hemiplegic children. Dev Med Child Neurol 29:287–303. https://doi.org/10.1111/j.1469-8749.1987.tb02482.x CrossRefPubMedGoogle Scholar
- Elder GC, Kirk J, Stewart G, Cook K, Weir D, Marshall A, Leahey L (2003) Contributing factors to muscle weakness in children with cerebral palsy. Dev Med Child Neurol 45:542–550. https://doi.org/10.1111/j.1469-8749.2003.tb00954.x CrossRefPubMedGoogle Scholar
- Jo HJ, Maenza C, Good DC, Huang X, Park J, Sainburg RL, Latash ML (2016) Effects of unilateral stroke on multi-finger synergies and their feed-forward adjustments. Neuroscience 319:194–205. https://doi.org/10.1016/j.neuroscience.2016.01.054 CrossRefPubMedPubMedCentralGoogle Scholar
- Latash ML, Huang X (2015) Neural control of movement stability: lessons from studies of neurological patients. Neuroscience 301:39–48. https://doi.org/10.1016/j.neuroscience.2015.05.075 CrossRefPubMedPubMedCentralGoogle Scholar
- Smith LR, Lee KS, Ward SR, Chambers HG, Lieber RL (2011) Hamstring contractures in children with spastic cerebral palsy result from a stiffer extracellular matrix and increased in vivo sarcomere length. J Physiol 589:2625–2639. https://doi.org/10.1113/jphysiol.2010.203364 CrossRefPubMedPubMedCentralGoogle Scholar