THE ROLE OF MIRROR NEURON SYSTEM ACTIVATION IN FACILITATING GOAL-DIRECTED ACTION OBSERVATION THERAPY FOR CHILDREN WITH UNILATERAL CEREBRAL PALSY
Main Article Content
Keywords
Mirror Neuron System, Action Observation Therapy, Cerebral Palsy, Pediatric Neurorehabilitation, fMRI, Upper Extremity, Neuroplasticity
Abstract
Background: Action Observation Therapy (AOT) shows promise in pediatric neurorehabilitation for improving upper limb function. Its proposed mechanism, mirror neuron system (MNS) activation, is largely inferred from adult studies, creating a significant evidence gap in children with unilateral cerebral palsy (UCP).
Objective: This study aimed to directly measure MNS activation via functional MRI (fMRI) in children with UCP during a goal-directed AOT paradigm and correlate it with functional motor improvements.
Methods: In a randomized controlled trial, 30 children with UCP (ages 6-12, MACS I-III) were allocated to either AOT (n=15) or control (n=15) groups. The AOT group observed goal-directed actions followed by physical practice, while the control group observed geometric shapes followed by the same practice. Pre- and post-intervention assessments included fMRI scans during action observation and the Assisting Hand Assessment (AHA) and Melbourne Assessment 2 (MA2) for functional evaluation.
Results: The AOT group demonstrated significantly greater activation in key MNS regions (inferior frontal gyrus, premotor cortex, inferior parietal lobule) on fMRI (p < 0.001, FWE-corrected). This was coupled with significantly greater improvement on the AHA (mean difference +5.6 points, p=0.002) and MA2 (mean difference +7.1%, p=0.005) compared to the control group. A strong positive correlation was found between the change in MNS activation and the change in AHA scores (r = 0.78, p < 0.001).
Conclusion: This study provides the first direct evidence in a pediatric population that functional gains from goal-directed AOT are mediated by the activation of the MNS. It validates AOT as a neuroplasticity-based intervention and underscores the importance of goal-directed action observation in designing effective rehabilitation protocols for children with UCP.
References
2. Buccino, G., Solodkin, A., & Small, S. L. (2006). Functions of the mirror neuron system: Implications for neurorehabilitation. Cognitive and Behavioral Neurology, 19(1), 55-63. https://doi.org/10.1097/00146965-200603000-00009
3. Celnik, P., Webster, B., Glasser, D. M., & Cohen, L. G. (2008). Effects of action observation on physical training after stroke. Stroke, 39(6), 1814-1820. https://doi.org/10.1161/ STROKEAHA.107.508184
4. Dinomais, M., Groeschel, S., Staudt, M., Krägeloh-Mann, I., & Wilke, M. (2016). Long term motor function after neonatal stroke: Lesion localization above all. Human Brain Mapping, 37(12), 4793-4806. https://doi.org/10.1002/hbm.23345
5. Ertelt, D., Small, S., Solodkin, A., Dettmers, C., McNamara, A., Binkofski, F., & Buccino, G. (2007). Action observation has a positive impact on rehabilitation of motor deficits after stroke. NeuroImage, 36(Suppl 2), T164-T173. https://doi.org/10.1016/j.neuroimage.2007.03.043
6. Franceschini, M., Ceravolo, M. G., Agosti, M., Cavallini, P., Bonassi, S., Dall'Armi, V., ... & Sale, P. (2012). Clinical relevance of action observation in upper-limb stroke rehabilitation: A possible role in recovery of functional dexterity. A randomized clinical trial. Neurorehabilitation and Neural Repair, 26(5), 456-462. https://doi.org/10.1177/ 1545968311427406
7. Garry, M. I., Loftus, A., & Summers, J. J. (2005). Mirror, mirror on the wall: Viewing a mirror reflection of unilateral hand movements facilitates ipsilateral M1 excitability. Experimental Brain Research, 163(1), 118-122. https://doi.org/10.1007/s00221-005-2226-9
8. Johnston, M. V. (2009). Plasticity in the developing brain: Implications for rehabilitation. Developmental Disabilities Research Reviews, 15(2), 94-101. https://doi.org/10.1002/ddrr.64
9. Kirkpatrick, E., Pearse, J., James, P., & Basu, A. (2016). Effect of parent-delivered action observation therapy on upper limb function in children with hemiplegic cerebral palsy: A randomized controlled trial. Developmental Medicine & Child Neurology, 58(10), 1049-1056. https://doi.org/10.1111/dmcn.13156
10. Krumlinde-Sundholm, L., Holmefur, M., Kottorp, A., & Eliasson, A. C. (2007). The Assisting Hand Assessment: Current evidence of validity, reliability, and responsiveness to change. Developmental Medicine & Child Neurology, 49(4), 259-264. https://doi.org/10.1111/j.1469-8749.2007.00259.x
11. Molenberghs, P., Cunnington, R., & Mattingley, J. B. (2012). Brain regions with mirror properties: A meta-analysis of 125 human fMRI studies. Neuroscience & Biobehavioral Reviews, 36(1), 341-349. https://doi.org/10.1016/j.neubiorev.2011.07.004
12. Novak, I., Morgan, C., Adde, L., Blackman, J., Boyd, R. N., Brunstrom-Hernandez, J., ... & Badawi, N. (2017). Early, accurate diagnosis and early intervention in cerebral palsy: Advances in diagnosis and treatment. JAMA Pediatrics, 171(9), 897-907. https://doi.org/10.1001/ jamapediatrics.2017.1689
13. Oskoui, M., Coutinho, F., Dykeman, J., Jetté, N., & Pringsheim, T. (2013). An update on the prevalence of cerebral palsy: A systematic review and meta-analysis. Developmental Medicine & Child Neurology, 55(6), 509-519. https://doi.org/10.1111/dmcn.12080
14. Randall, M., Carlin, J. B., Chondros, P., & Reddihough, D. (2012). Reliability of the Melbourne Assessment of Unilateral Upper Limb Function. Developmental Medicine & Child Neurology, 43(11), 761-767. https://doi.org/10.1111/j.1469-8749.2001.tb00162.x
15. Rizzolatti, G., & Craighero, L. (2004). The mirror-neuron system. Annual Review of Neuroscience, 27, 169-192. https://doi.org/10.1146/annurev.neuro.27.070203.144230
16. Sakzewski, L., Ziviani, J., & Boyd, R. N. (2014). Efficacy of upper limb therapies for unilateral cerebral palsy: A meta-analysis. Pediatrics, 133(1), e175-e204. https://doi.org/10.1542/peds. 2013-0675
17. Sgandurra, G., Ferrari, A., Cossu, G., Guzzetta, A., Biagi, L., Tosetti, M., ... & Cioni, G. (2013). Upper limb children action-observation training (UP-CAT): A randomised controlled trial in hemiplegic cerebral palsy. BMC Neurology, 13, 76. https://doi.org/10.1186/1471-2377-13-76
18. Shimada, S., & Hiraki, K. (2006). Infant's brain responses to live and televised action. NeuroImage, 32(2), 930-939. https://doi.org/10.1016/j.neuroimage.2006.03.044
19. Staudt, M. (2010). Brain plasticity following early life brain injury: Insights from neuroimaging. Seminars in Perinatology, 34(1), 87-92. https://doi.org/10.1053/j.semperi. 2009.10.009