Magnetic resonance imaging (MRI) and functional MRI now combine a

Magnetic resonance imaging (MRI) and functional MRI now combine analysis of anatomy and function. EEG, event-related potential, and and magnetoencephalography have undergone a considerable

development in signal post-processing and in source localization with new realistic models. Other techniques such as magnetic stimulation have been combined with previous ones in order to improve the data Inhibitors,research,lifescience,medical and find the best compromise between spatial and temporal resolution of the techniques. These technical improvements have provided new data regarding spontaneous post-stroke brain plasticity in humans. Observed phenomena Reorganization of brain metabolism, recruitment of remote areas, overactivation of cortices, and changes in cortical maps have been identified as the main observed changes in patients with stroke undergoing

at least partial recovery of neurological function.26-29 Recruitment of remote areas has been shown both in patients with motor deficit and in patients with aphasia. It concerns both primary and associative cortices. This is particularly the Inhibitors,research,lifescience,medical case for premotor cortex, Inhibitors,research,lifescience,medical supplementary motor area, and check details inferior parietal cortex, through anatomical identified projection on the corticospinal tract. Changes in cortical maps were demonstrated in recovering stroke patients with upper-limb motor deficit, as it had been before in patients with peripheral facial palsy or in patients with amyotrophic lateral sclerosis. While motor and premotor cortices were overactivated compared with controls, the peak of fMRI activation was located 5 mm to 10 mm below the M1 hand area in the Inhibitors,research,lifescience,medical area governing the face motor control. Posterior translation towards P1 of the peak of activation was also observed. This probably corresponds to the unmasking of neuron activity.

Contralesional axonal remodeling of the corticospinal system has been demonstrated only recently in animal model experiments. However, the capacity for remodeling of the corticospinal tract axons at the spinal cord level remains to be demonstrated in stroke patients.26-29 Inhibitors,research,lifescience,medical Time course It is now well established that these phenomena MTMR9 can not be observed in all patients and at all stages of the post-stroke recovery period. Many studies using neuroimaging techniques have contributed to better understanding of the time course of the observed intracerebral reorganization phenomena with regard to clinical recovery of neurological functions. For example, in aphasic patients studied at the acute phase of the stroke and 1 year later, the improvement of the clinical aphasia scores was associated with a strong reduction in the number of activated areas of the linguistic network. This was also observed in motor-recovering patients. Briefly, in patients with good recovery, linguistic networks were close to those observed in normals, while in patients with poor recovery a much more widespread activation of remote areas was still observed.

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