Multimodal imaging of brain reorganization in motor areas of the contralesional hemisphere of well recovered patients after capsular stroke

 In 15 years has ANYTHING AT ALL been done with this to create recovery protocols?  Or is your doctor using the fucking statement; 'All strokes are different, all stroke recoveries are different' to justify inaction?

Multimodal imaging of brain reorganization in motor areas of the contralesional hemisphere of well recovered patients after capsular stroke

  Christian Gerloff, 1,2
Khalaf Bushara, 2
Alexandra Sailer, 1
Eric M. Wassermann, 4
Robert Chen, 2
Takahiro Matsuoka, 2
Daniel Waldvogel, 2
George F. Wittenberg, 3
Kenji Ishii, 2
Leonardo G. Cohen 3
and Mark Hallett 2
1 Cortical Physiology Research Group, Department of Neurology, Eberhard–Karls University Medical School, Tuebingen,Germany; Sections of
 2 Human Motor Control and 3 Human Cortical Physiology, Medical Neurology Branch and
 4 BrainStimulation Unit, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA

Correspondence to: Christian Gerloff, MD, Department of General Neurology, Hertie Institute for Clinical Brain Research,University of Tuebingen, Hoppe-Seyler Street 3, 72076 Tuebingen, Germany E-mail: christian.gerloff@uni-tuebingen.de orMark Hallett, MD, NINDS, National Institutes of Health, 10 Center Drive, MSC-1428, Bethesda, Maryland 20892, USA,E-mail: hallettm@ninds.nih.gov
 

 

Clinical recovery after stroke can be significant and has been attributed to plastic reorganization and recruitment of novel areas previously not engaged in a given task. As equivocal results have been reported in studies using single imaging or electrophysiological methods, here we applied an integrative multimodal approach to a group of well-recovered chronic stroke patients (n=11; aged 50–81 years) with left capsular lesions. Focal activation during recovered hand movements was assessed with EEG spectral analysis and H₂¹⁵O-PET withEMG monitoring, cortico–cortical connectivity with EEG coherence analysis (cortico–cortical coherence) and corticospinal connectivity with transcranial magnetic stimulation (TMS). As seen from comparisons with age-matched controls, our patients showed enhanced recruitment of the lateral premotor cortex of the lesioned hemisphere [Brodmann area (BA) 6], lateral premotor and to a lesser extent primary sensorimotor andparietal cortex of the contralesional hemisphere (CON-H; BA 4 and superior parietal lobule) and left cerebellum (patients versus controls, Z  > 3.09). EEG coherence analysis showed that after stroke cortico–cortical connections were reduced in the stroke hemisphere but relatively increased in the CON-H (ANOVA, contrast analysis, P <0.05), suggesting a shift of functional connectivity towards the CON-H. Nevertheless, fast con-ducting corticospinal transmission originated exclusively from the lesioned hemisphere. No direct ipsilateral motor evoked potentials (MEPs) could be elicited with TMS over the contralesional primary motor cortex(iM1)in stroke patients. We conclude that (i) effective recovery is based on enhanced utilization of ipsi- and contralesional resources, (ii) basic corticospinal commands arise from the lesioned hemisphere without recruitment of (‘latent’) uncrossed corticospinal tract fibres and (iii) increased contralesional activity probably facilitates control of recovered motor function by operating at a higher-order processing level, similar to but not identical with the extended network concerned with complex movements in healthy subjects.Keywords
: Plasticity; stroke; recovery; motor control; motor cortex