Cerebral stroke remains one of the leading causes of death and disability in patients, leaving in some cases significant neurological deficit. Motor activity is controlled by a motor system, which consists of a number of cortical and subcortical areas interacting through a system of anatomical, functional, effective and network connectivity. Damage to any of these areas or systems of connectivity entails a violation of the motor function. There is some evidence pointing to reappraisal motor networks, including the reorganization of brain areas and different types of connectivity that promotes the recovery of motor functions. The neurophysiological mechanisms that allow recovering the motor functions of stroke patients are various. In the early period (first days and weeks after stroke), the importance represents the recovery of the functional activity of morphologically intact but temporarily disorganized neurons located perifocal in relation to the lesion. This is possible due to the resolution of edema, developing in the first weeks after stroke, and development of collateral circulation and restore perfusion of the affected brain areas. Further neurophysiological basis of recovery became the processes of brain plasticity related to reorganization of normal physiological connectivity between various brain structures involved in the implementation of motor function. Plastic changes can take place at all levels of the CNS, however, most often, based plasticity is the reprogramming or modification of the architecture of neural networks. The phenomenon of plasticity was in various brain regions, including the cortex and subcortical structures. This article presents the results of recent studies which describe models of anatomical, functional, effective connectivity, and examine influences of ischemia on motor function and functional recovery. It is assumed that the changing relations constitute an important pathophysiological aspect of influence, on the one hand on the volume of motor deficits in post-stroke patients, on the other hand is an extremely important mechanism involved in the recovery of lost motor functions. Study of structural and functional changes after stroke using neuroimaging techniques such as magnetic resonance imaging (MRI), has made a significant contribution to our understanding of the mechanisms of recovery of motor activity after ischemic brain damage. Application of these methods can provide a deeper understanding of the processes of dysfunction and functional reorganization as a result of activation of certain areas of the brain that can be the subject of study with the goal of predicting outcomes and the development of new therapeutic direction.

Keywords: stroke, motor impairments, brain plasticity, neural connectivity, MRI

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1. Cramer SC. Repairing the human brain after stroke: I. Mechanisms of spontaneous recovery. Annals of Neurology. 2008; 63 (3): 272–87. https://doi.org/10.1002/ana.21393
2. Luft AR, Hafer-Macko C, Schallert T. Physiological basis of rehabilitation therapeutics in stroke. Stroke recovery and rehabilitation. Edited by Stein J, Harvey RL, Macko RF, Winstein CJ, Zorowitz RD. New York, USA: Demos Medical Publishing; 2009. р.145-152.
3. Farr TD and Wegener S. Use of magnetic resonance imaging to predict outcome after stroke: a review of experimental and clinical evidence. Journal of Cerebral Blood Flow and Metabolism. 2010; 30 (4): 703–17. https://doi.org/10.1038/jcbfm.2010.5
4. Brodtmann A, Pardoe H, Li Q, Lichter R, Ostergaard L, and Cumming T. Changes in regional brain volume three monthsafter stroke. Journal of the Neurological Sciences. 2012; 322 (1): 122–8. https://doi.org/10.1016/j.jns.2012.07.019
5. Saur D, Lange R, Baumgaertner A, et al. Dynamics of language reorganization after stroke. Brain. 2006; 129 (6): 1371–84. https://doi.org/10.1093/brain/awl090
6. Buckner RL, Corbetta M, Schatz J, Raichle ME, and Petersen SE. Preserved speech abilities and compensation following prefrontal damage. Proceedings of the National Academy of Sciences of the United States of America. 1996; 93 (3): 1249– 53. https://www.ncbi.nlm.nih.gov/pmc/articles/40065
7. Grefkes C, Nowak DA, Eickhoff SB, Dafotakis M, Küst J, Karbe H, Fink GR. Cortical connectivity after subcortical stroke assessed with functionalmagnetic resonance imaging. Annals of Neurology. 2008; 63 (2): 236–46. https://doi.org/10.1002/ana.21228
8. Kim YR, van Meer MPA, Tejima E, Yoshi Murata, Joseph B. Mandeville, George Dai, De-Maw Chuang, Bruce R. Rosen, Eng H. Lo. Functional MRI of delayed chronic lithium treatment in rat focal cerebral ischemia. Stroke. 2008; 39 (2): 439–47. https://doi.org/10.1161/STROKEAHA.107.492215
9. Bestmann S, Swayne O, Blankenburg F, Christian C Ruff, James Teo, Nikolaus Weiskopf, Jon Driver, John C Rothwell, Nick S Ward. The role of contralesional dorsal premotor cortex after stroke as studied with concurrent TMS-fMRI. Journal of Neuroscience. 2010; 30 (36): 11926–37. https://doi.org/10.1523/JNEUROSCI.5642-09.2010
10. Feydy A, Carlier R, Roby-Brami A, Bussel B, Cazalis F, Pierot L, Burnod Y, Maier MA. Longitudinal study of motor recovery after stroke: recruitment and focusing of brain activation. Stroke. 2002; 33 (6): 1610–7. https://www.ncbi.nlm.nih.gov/pubmed/12053000
11. Stephan KE, Harrison LM, Kiebel SJ, David O, Penny WD, and Friston KJ. Dynamic causal models of neural system dynamics: current state and future extensions. Journal of Biosciences. 2007; 32 (1): 129–44. https://www.ncbi.nlm.nih.gov/pubmed/17426386. PMCID: PMC2636905
12. Friston K. Functional integration and inference in the brain. Progress in Neurobiology. 2002; 68 (2): 113–43. https://doi.org/10.1016/S0301-0082(02)00076-X
13. Le Bihan D. Looking into the functional architecture of the brain with diffusion MRI. Nature Reviews Neuroscience. 2003; 4 (6): 469–80. https://doi.org/10.1038/nrn1119
14. Mori S, Crain BJ, Chacko VP, and van Zijl PC. Three dimensional tracking of axonal projections in the brain bymagnetic resonance imaging. Annals of Neurology. 1999; 45: 265–9. https://www.ncbi.nlm.nih.gov/pubmed/9989633
15. Assaf Y and Pasternak O. Diffusion tensor imaging (DTI)-basedwhite matter mapping in brain research: a review. Journal of Molecular Neuroscience. 2008; 34 (1): 51–61. https://doi.org/10.1007/s12031-007-0029-0
16. Jiang Q, Zhang ZG, Chopp M. MRI of stroke recovery. Stroke. 2010; 41 (2): 410–4. https://doi.org/10.1161/STROKEAHA.109.568048
17. He BJ, Snyder AZ, Zempel JM, Smyth MD, Raichle ME. Electrophysiological correlates of the brain’s intrinsic large-scale functional architecture. Proceedings of the National Academy of Sciences of the United States of America. 2008; 105 (41): 16039–44. https://doi.org/10.1073/pnas.0807010105
18. Lu J, Liu H, Zhang M, Wang D, Cao Y, Ma Q, Rong D, Wang X, Buckner RL, Li K. Focal pontine lesions provide evience that intrinsic functional connectivity reflects polysynaptic anatomical pathways. The Journal of Neuroscience. 2011; 31 (42): 15065–71. https://doi.org/10.1523/JNEUROSCI.2364-11.2011
19. Xuan Y, Meng C, Yang Y, Zhu C, Wang L, Yan Q, Lin C, Yu C. Resting-state brain activity in adult males who stutter. PLoS One. 2012; 7 (1): ID e30570. https://doi.org/10.1371/journal.pone.0030570
20. Tomasi D, Volkow ND. Association between functional connectivity hubs and brain networks. Cerebral Cortex. 2011; 21: 2003–13. https://doi.org/10.1093/cercor/bhq268
21. Roebroeck A, Formisano E, Goebel R. Mapping directed influence over the brain using Granger causality and fMRI. NeuroImage. 2005; 25 (1): 230–42. https://doi.org/10.1016/j.neuroimage.2004.11.017
22. Rubinov M, Sporns O. Complex network measures of brain connectivity: uses and interpretations. NeuroImage. 2010; 52: 1059–69. https://doi.org/10.1016/j.neuroimage.2009.10.003
23. Jang SH. A review of diffusion tensor imaging studies on motor recovery mechanisms in stroke patients. NeuroRehabilitation. 2011; 28: 345–52. https://doi.org/10.3233/NRE-2011-0662
24. Pannek K, Chalk JB, Finnigan S, Rose SE. Dynamic corticospinal white matter connectivity changes during stroke recovery: a diffusion tensor probabilistic tractography study. Journal of Magnetic Resonance Imaging. 2009; 29 (3): 529– 36. https://doi.org/10.1002/jmri.21627
25. Schaechter JD, Fricker ZP, Perdue KL, Karl G. Helmer, Mark G. Vangel, Douglas N. Greve, Nikos Makris. Microstructural status of ipsilesional and contralesional corticospinal tract correlates with motor skill in chronic stroke patients. Human Brain Mapping. 2009; 30 (11): 3461–74. https://doi.org/10.1002/hbm.20770
26. Yu C, Zhu C, Zhang Y, Chen H, Qin W, Wang M, Li K. A longitudinal diffusion tensor imaging study on Wallerian degeneration of corticospinal tract aftermotor pathway stroke. NeuroImage. 2009; 47 (2): 451–8. https://doi.org/10.1016/j.neuroimage.2009.04.066
27. Liu Y, D’Arceuil HE, Westmoreland S, He J, Duggan M, Gonzalez RG, Pryor J, de Crespigny AJ. Serial diffusion tensor MRI after transient and permanent cerebral ischemia in nonhuman primates. Stroke. 2007;38(1):138–45. https://doi.org/10.1161/01.STR.0000252127.07428.9c
28. Ding G, Jiang Q, Li L, Zhang L, Zhang ZG, Ledbetter KA, Panda S, Davarani SP, Athiraman H, Li Q, Ewing JR, Chopp M. Magnetic resonance imaging investigation of axonal remodeling and angiogenesis after embolic stroke in sildenafil-treated rats. Journal of Cerebral Blood Flow and Metabolism. 2008; 28 (8): 1440–8. https://doi.org/10.1038/jcbfm.2008.33
29. Ahn YH, You SH, Randolph M, et al. Peri-infarct reorganization of motor function in patients with pontine infarct. NeuroRehabilitation. 2006; 21 (3): 233–7.
30. Yeo SS, Jang SH. Ipsilateral motor pathway without contralateral motor pathway in a stroke patient. NeuroRehabilitation. 2012; 30 (4): 303–6. https://doi.org/10.3233/NRE-2012-0759
31. Zaaimi B, Edgley SA, Soteropoulos DS, Baker SN. Changes in descending motor pathway connectivity after corticospinal tract lesion in macaque monkey. Brain. 2012; 135 (7): 2277–89. https://doi.org/10.1093/brain/aws115
32. Kwon HG, Son SM, Chang MC, Kim S, Kwon YH, Jang SH. Characteristics of the aberrant pyramidal tract in comparison with the pyramidal tract in the human brain. BMC Neuroscience. 2011; 12: article 108.
33. Hong JH, Jang SH. Aberrant pyramidal tract in a patient with coronaradiata infarct a diffusion tensor tractographystudy. Neural Regeneration Research. 2011; 6 (13): 1027–30.
34. Rёuber T, Schlaug G, Lindenberg R. Compensatory role of the cortico-rubro-spinal tract inmotor recovery after stroke. Neurology. 2012; 79 (6): 515–22. https://doi.org/10.1212/WNL.0b013e31826356e8
35. van Meer MPA, van der Marel K, Wang K, Otte WM, El Bouazati S, Roeling TA, Viergever MA, Berkelbach van der Sprenkel JW, Dijkhuizen RM. Recovery of sensorimotor function after experimental stroke correlates with restoration of resting-state interhemispheric functional connectivity. Journal of Neuroscience. 2010; 30 (11): 3964–72. https://doi.org/10.1523/JNEUROSCI.5709-09.2010
36. van Meer MPA, van der Marel K, Otte WM, Berkelbach van der Sprenkel JW, Dijkhuizen RM. Correspondence between altered functional and structural connectivity in the contralesional sensorimotor cortex after unilateral stroke in rats: a combined resting-state functional MRI and manganeseenhanced MRI study. Journal of Cerebral Blood Flow and Metabolism. 2010; 30 (10): 1707–11. https://doi.org/10.1038/jcbfm.2010.124
37. van Meer MP, Otte WM, van der Marel K, Nijboer CH, Kavelaars A, van der Sprenkel JW, Viergever MA, Dijkhuizen RM. Extent of bilateral neuronal network reorganization and functional recovery in relation to stroke severity. The Journal of Neuroscience. 2012; 32 (13): 4495–507. https://doi.org/10.1523/JNEUROSCI.3662-11.2012
38. Golestani AM, Tymchuk S, Demchuk A, Bradley G Goodyear. Longitudinal evaluation of resting-state FMRI after acute stroke with hemiparesis. Neurorehabilitation and Neural Repair. 2013; 27 (2): 153–63. https://doi.org/10.1177/1545968312457827
39. Park CH, Chang WH, Ohn SH, Kim ST, Bang OY, Pascual-Leone A, Kim YH. Longitudinal changes of resting-state functional connectivity during motor recovery after stroke. Stroke. 2011; 42 (5): 1357–62. https://doi.org/10.1161/STROKEAHA.110.596155
40. Carter AR, Patel KR, Astafiev SV, Snyder AZ, Rengachary J, Strube MJ, Pope A, Shimony JS, Lang CE, Shulman GL, Corbetta M. Upstream dysfunction of somatomotor functional connectivity after corticospinal damage in stroke. Neurorehabilitation and Neural Repair. 2012; 26: 7–19. https://doi.org/10.1177/1545968311411054
41. Rehme AK, Eickhoff SB, Wang LE, Fink GR, Grefkes C. Dynamic causal modeling of cortical activity fromthe acute to the chronic stage after stroke. NeuroImage. 2011; 55 (3): 1147–58. https://doi.org/10.1016/j.neuroimage.2011.01.014
42. Sharma N, Baron JC, Rowe JB. Motor imagery after stroke: relating outcome tomotor network connectivity. Annals of Neurology. 2009; 66 (5): 604–16. https://doi.org/10.1002/ana.21810
43. Inman CS, James GA, Hamann S, Rajendra JK, Pagnoni G, Butler AJ. Altered resting-state effective connectivity of fronto-parietal motor control systems on the primary motor network following stroke. NeuroImage. 2012; 59: 227–37. https://doi.org/10.1016/j.neuroimage.2011.07.083
44. de Vico Fallani F, Astolfi L, Cincotti F, Mattia D, la Rocca D, Maksuti E, Salinari S, Babiloni F, Vegso B, Kozmann G, Nagy Z. Evaluation of the brain network organization fromEEG signals: a preliminary evidence in stroke patient. Anatomical Record. 2009; 292 (12): 2023–31. https://doi.org/10.1002/ar.20965
45. Wang L, Yu C, Chen H, Qin W, He Y, Fan F, Zhang Y, Wang M, Li K, Zang Y, Woodward TS, Zhu C. Dynamic functional reorganization of the motor execution network after stroke. Brain. 2010; 133 (4): 1224–38. https://doi.org/10.1093/brain/awq043
46. Cheng L, Wu Z, Fu Y, Miao F, Sun J, Tong S. Reorganization of functional brain networks during the recovery of stroke: a functional MRI study. In Proceedings of AnnualInternational Conference of the IEEE Engineering in Medicine and Biology Society (EMBC ’12). 2012: 4132–5. https://doi.org/10.1109/EMBC.2012.6346876
47. Crofts JJ, Higham DJ, Bosnell R, Jbabdi S, Matthews PM, Behrens TE, Johansen-Berg H. Network analysis detects changes in the contralesional hemisphere following stroke. NeuroImage. 2011; 54 (1): 161–9. https://doi.org/10.1016/j.neuroimage.2010.08.032