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In lower mammals, locomotion seems to be mainly regulated by subcortical and spinal networks. On the contrary, recent evidence suggests that in humans the motor cortex is also significantly engaged during complex locomotion tasks. However, a detailed understanding of cortical contribution to locomotion is still lacking especially during stereotyped activities. Here, we show that cortical motor areas finely control leg muscle activation during treadmill stereotyped walking. Using a novel technique based on a combination of Reliable Independent Component Analysis, source localization and effective connectivity, and by combining electroencephalographic (EEG) and electromyographic (EMG) recordings in able-bodied adults we were able to examine for the first time cortical activation patterns and cortico-muscular connectivity including information flow direction. Results not only provided evidence of cortical activity associated with locomotion, but demonstrated significant causal unidirectional drive from contralateral motor cortex to muscles in the swing leg. These insights overturn the traditional view that human cortex has a limited role in the control of stereotyped locomotion, and suggest useful hypotheses concerning mechanisms underlying gait under other conditions.One sentence summaryMotor cortex proactively drives contralateral swing leg muscles during treadmill walking, counter to the traditional view of stereotyped human locomotion.

Aim of this study is to examine caregiver burden and family functioning in different neurological conditions. Forty-two primary caregivers of patients with Amyotrophic Lateral Sclerosis (ALS), Alzheimer’s Disease and other dementia (AD), Parkinson’s Disease (PD), Acquired Brain Injuries (ABI) and Multiple Sclerosis (MS) were administered scales for the evaluation of caregiver burden (CBI) and family functioning (FACES IV). Caregiver burden was overall high, with caregivers of patients with ALS and ABI having exceeded the CBI cut-off score for possible burn-out. The average scores of caregivers of patients with AD or other dementia and PD were close to the cut-off score, whereas those of caregivers of patients with MS were significantly lower than the others. Family cohesion, family satisfaction and the quality of family communication were associated with reduced levels of caregiver burden, whereas disengagement was associated with a higher burden. The data from the present study confirm that caregiver burden is a relevant issue in the context of neurological diseases, especially for those causing higher degrees of impairment. Significant correlations with family functioning emerged as well, highlighting the importance of studying and treating caregiver burden within the context of family relations. [ABSTRACT FROM AUTHOR]

Background: Gait and mobility impairments are common in progressive multiple sclerosis (MS), leading to reduced quality of life (QoL). Objective: In this randomized controlled study, we tested the effects of robot-assisted gait training (RAGT) and compared it to conventional physiotherapy, measuring walking ability, depression, fatigue, and QoL in patients with progressive MS and severe gait disability. Methods: Fifty-two participants (Expanded Disability Status Scale score 6–7) completed the study protocol. They received two sessions/week over 6 weeks of RAGT or conventional walking therapy. Outcome measures were Six-Minute Walk Test, Ten-Meter Walk Test, Timed Up and Go Test, Berg Balance Scale, Fatigue Severity Scale, Patient Health Questionnaire, and Short Form 36. They were performed pre-treatment, post-treatment, and at 3 months. Results: Walking endurance (p < 0.01) and balance (p < 0.01) were improved among those in the RAGT group. Positive effects on depression in both treatment groups were highlighted. However, only among those in the RAGT group was perceived physical functioning QoL increased. No significant effects on fatigue were found. Conclusion: RAGT is a treatment option in progressive MS patients with severe gait impairments to induce short-lasting effects on mobility and QoL. [ABSTRACT FROM AUTHOR]

What determines motor recovery in stroke is still unknown and finding markers that could predict and improve stroke recovery is a challenge. In this study, we aimed at understanding the neural mechanisms of motor function recovery after stroke using neurophysiological markers by means of cortical excitability (transcranial magnetic stimulation—TMS) and brain oscillations (electroencephalography—EEG). In this cross-sectional study, 55 subjects with chronic stroke (62 ± 14 yo, 17 women, 32 ± 42 months post-stroke) were recruited in two sites. We analyzed TMS measures (i.e., motor threshold—MT—of the affected and unaffected sides) and EEG variables (i.e., power spectrum in different frequency bands and different brain regions of the affected and unaffected hemispheres) and their correlation with motor impairment as measured by Fugl-Meyer. Multiple univariate and multivariate linear regression analyses were performed to identify the predictors of good motor function. A significant interaction effect of MT in the affected hemisphere and power in beta bandwidth over the central region for both affected and unaffected hemispheres was found. We identified that motor function positively correlates with beta rhythm over the central region of the unaffected hemisphere, while it negatively correlates with beta rhythm in the affected hemisphere. Our results suggest that cortical activity in the affected and unaffected hemisphere measured by EEG provides new insights on the association between high-frequency rhythms and motor impairment, highlighting the role of an excess of beta in the affected central cortical region in poor motor function in stroke recovery.

Background: Neurophysiological investigations represent powerful tools to shed light on brain plasticity in multiple sclerosis (MS) patients., Aim: We investigated the relationship between electroencephalography (EEG)-based connectivity, the extent of brain lesions and changes in motor performance after an intensive task-oriented circuit training (TOCT)., Design: Observational longitudinal study., Setting: Outpatients training program., Population: Sixteen MS patients (10F; mean age =51.4 years; range: 27-67; mean disease duration =15.1 years; range: 2-26; mean Expanded Disability Status Scale 4.4; range: 3.5-5.5), were included in our study., Methods: MS patients with mild gait impairment were evaluated through functional scales and submitted to TOCT. Resting-state EEG was performed before (T0) and after (T1) rehabilitation. Alpha-band weighted Phase Lag Index (wPLI) and broadband weighted Symbolic Mutual Information (wSMI) connectivity analyses were performed. White matter lesion load was measured using MRI prior to the TOCT. Neurophysiological and structural parameters were then related to behavioral changes., Results: Dynamic Gait Index significantly improved after TOCT (F(1,14) =13.10, P=0.003). Moreover, the interaction between TOCT and age was observed for changes in Timed Up and Go (TUG) performance (F(1,14) = 7.75, P=0.015), indicating that older patients only benefited in this measure. Regarding the relationship between EEG connectivity and TOCT outcome, we observed positive correlations between changes in TUG and strength (P=0.017) and efficiency (Pone-tail =0.029) of alpha-band wPLI connectivity at T0. Such correlation was mainly driven by antero-posterior regional interactions (P=0.038), rather than by inter-hemispheric connectivity (P=0.089). Moreover, we observed a positive correlation between performance improvements and wSMI connectivity at T1 (P=0.001) as well as the difference between T0 and T1 (P=0.005). Lesion load percentage was not related to functional improvement after TOCT (Pone-tail=0.137)., Conclusions: Results of the current study demonstrated that baseline alpha-band wPLI connectivity predicts TOCT outcome in MS patients. Moreover, broadband wSMI tracks neural changes that accompany treatment-related variations in motor performance., Clinical Rehabilitation Impact: Our findings suggest that EEG-based connectivity measures may represent a potential tool for customizing rehabilitative management of the disease.

Through plasticity the brain is able to change its function and to rearrange following injury or environmental changes. In recent years, it was shown that non-invasive brain stimulation (NIBS) techniques, especially transcra- nial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) can contribute to understand how these plastic changes occur. Additionally, the literature suggests that TMS and tDCS may be used as interven- tional strategies to improve neurorehabilitation efforts and arguably recovery of motor function after brain lesions. This review focuses on the use of NIBS in experimental protocols for evaluation and modulation of brain plastic- ity, the factors contributing to the inter-individual variability of response, proposed mechanisms and difficulties in translating findings from small proof of principle studies through the pipeline to clinical practice.

Emerging findings deriving from neuromodulation and neuroradiology are providing us new insights about plas- ticity and functional reorganization of the brain after stroke, but the direct clinical assessment of motor function should still be considered an indispensable tool for the evaluation of the effects of plasticity in stroke patients. Recovery of motor function can be spontaneous or guided by training. Substantial functional recovery can occur spontaneously especially in the first month post-stroke. Instead, the guided recovery may take more time and may rely on a number of rehabilitation techniques which proved to be capable of stimulating cerebral plasticity. Even the time course of these processes is a decisive element. First, it is important to correlate the trends of plasticity after stroke, from the enhancement of earlier periods to the later stages, to the behavioral changes observed. Furthermore, it is crucial to distinguish recovery of function occurring through improvement of motor deficit from compensatory mechanisms, distinction that has also an effect on timing of recovery. Another relevant question is the maintenance over time of the improvements reached with the treatment, feature on which various clinical studies have been conducted in acute and chronic stroke patients. Further studies are needed to allow us to get a more precise definition of the potentiality of functional recovery and of the mechanisms underlying the recovery depending on its levels and timing. Understanding the mechanisms, the effects and the limits of neural plasticity may eventually help enhancing the recovery process in stroke patients, significantly improving the quality of life of these patients. Then, a greater attention towards the clinical implica- tions of the changes related to plasticity can be a crucial element to further improve the therapeutic options used in neurorehabilitation.