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Objectives: Gait impairment dramatically affects stroke patients' functional independence. The Ekso™ is a wearable powered exoskeleton able to improve over-ground gait abilities, but the relationship between the cortical gait control mechanisms and lower limbs kinematics is still unclear. Our aims are: to assess whether the Ekso™ induces an attention-demanding process with prefrontal cortex activation during a gait task; to describe the relationship between the gait-induced muscle activation pattern and the prefrontal cortex activity., Methods: We enrolled 22 chronic stroke patients and 15 matched controls. We registered prefrontal cortex (PFC) activity with functional Near-Infrared Spectroscopy (fNIRS) and muscle activation with surface-electromyography (sEMG) during an over-ground gait task, performed with and without the Ekso™., Results: We observed prefrontal cortex activation during normal gait and a higher activation during Ekso-assisted walking among stroke patients. Furthermore, we found that muscle hypo-activation and co-activation of non-paretic limb are associated to a high prefrontal metabolism., Conclusions: Among stroke patients, over-ground gait is an attention-demanding task. Prefrontal activity is modulated both by Ekso-assisted tasks and muscle activation patterns of non-paretic lower limb. Further studies are needed to elucidate if other Ekso™ settings induce different cortical and peripheral effects., Significance: This is the first study exploring the relationship between central and peripheral mechanisms during an Ekso-assisted gait task., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Objective: We tested whether acute cerebellar stroke may determine changes in brain network architecture as defined by cortical sources of EEG rhythms., Methods: Graph parameters of 41 consecutive stroke patients (<5 days from the event) were studied using eLORETA EEG sources. Network rearrangements of stroke patients were investigated in delta, alpha 2, beta 2 and gamma bands in comparison with healthy subjects., Results: The delta network remodeling was similar in cerebellar and middle cerebral artery strokes, with a reduction of small-worldness. Beta 2 and gamma small-worldness, in the right hemisphere of patients with cerebellar stroke, increase respect to healthy subjects, while alpha 2 small-worldness increases only among patients with a middle cerebral artery stroke., Conclusions: The network remodeling characteristics are independent on the size of the ischemic lesion. In the early post-acute stages cerebellar stroke differs from the middle cerebral artery one because it does not cause alpha 2 network remodeling while it determines a high frequency network reorganization in beta 2 and gamma bands with an increase of small-worldness characteristics., Significance: These findings demonstrate changes in the balance of local segregation and global integration induced by cerebellar acute stroke in high EEG frequency bands. They need to be integrated with appropriate follow-up to explore whether further network changes are attained during post-stroke outcome stabilization., (Copyright © 2019 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Gait impairment is one of the most frequent and life-altering consequences of Multiple sclerosis (MS), frequently associated with lower limb spasticity. Focal muscle vibration (fMV) is a technique that applies a vibratory stimulus to a specific muscle or its tendon, reducing spasticity. The aim of our study is to evaluate the efficacy of fMV in ameliorating gait impairment in MS patients with severe lower limb spasticity, measured by Gait Analysis (GA) and objective and patient-oriented scales scores. Fourteen patients affected by Secondary Progressive MS (SPMS) with a lower limb spasticity with a low or no response to antispastic drugs, received repetitive fMV (r-fMV) over the quadriceps and the lumbar paraspinal muscles. The effect of r-fMV on gait was measured by a GA evaluation and objective and patient-oriented scales scores, performed before r-fMV (T0), and 1week (T1) and 1month (T2) after the last session of r-fMV. After the r-fMV the most of spatio-temporal parameters calculated by GA were improved. Moreover, clinical evaluation related results showed an improvement of SM patients' quality of life. In conclusion, r-fMV improves gait function in MS patients affected by severe spasticity of lower limb, non-responsive to common oral antispastic drugs., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: Myotonic dystrophy type 1 (DM1), the most common muscular dystrophy in adults, is characterized by a multisystem involvement. Cognitive involvement predominantly affecting frono-temporal functions is an established clinical feature in this disorder. Brain imaging and metabolic studies showed a predominant involvement of fronto-temporal regions in DM1 patients, yet correlation studies among these findings and neuropsychological data gave contrasting results. In order to contribute to clarify the relationship between the metabolic changes documented in the frontal cortex of DM1 patients and a related cognitive task, we applied the functional near-infrared spectroscopy (fNIRS) during the execution of a phonemic verbal fluency task (pVFT)., Methods: We enrolled 29 consecutive right-handed DM1 patients and 30 controls. A 2-channel fNIRS imaging system was used to investigate changes in oxygenated [O2Hb] and deoxygenated [HHb] hemoglobin concentrations in the prefrontal cortex (PFC) during a pVFT. [O2Hb] and [HHb] baseline-corrected activation values were calculated (respectively [O2Hb]c and [HHb]c)., Results: In the control group [O2Hb] significantly increased and [HHb] significantly decreased during the pVFT, in the DM1 group no significant variation was found for both parameters revealing no activation of both PFCs during the task. On the other hand, in the DM1 sample, statistical analysis revealed a direct correlation between [O2Hb]c of the left PFC and the pVFT score, while no correlation was observed in the control group., Conclusions: Our study reveals that DM1 patients show prefrontal hypometabolism during a specific frontal cognitive task compared to controls. Moreover the rapid temporal discrimination of fNIRS allows revealing the correlation between the PFC hypometabolism and the cognitive performance in DM1 patients., Significance: fNIRS can be helpful to understand the functional correlates of the frontal cognitive impairment in DM1., (Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.)