Restorative neurology and neuroscience最新文献

Stroke remains a leading cause of disability worldwide, highlighting the need for innovative neurorehabilitation strategies to enhance recovery. Recent advancements emphasize neuroplasticity-the brain's ability to reorganize and form new connections-through targeted interventions. Among these, cortical priming has emerged as a promising approach to enhance neuroplasticity and improve motor recovery post-stroke by modulating brain excitability for optimal motor learning. This review explores the role of cortical priming in stroke rehabilitation, highlighting its ability to enhance neural excitability and plasticity in motor-related brain regions. Various priming techniques, including non-invasive brain stimulation (rTMS, tDCS), deep brain stimulation (DBS), vagus nerve stimulation (VNS), brain-computer interfaces (BCIs), movement-based priming, aerobic exercise, and sensory stimulation, are examined. Despite promising findings, challenges remain in optimizing protocols and addressing individual variability. Future directions focus on biomarker-driven rehabilitation, personalized strategies, and large-scale trials to integrate cortical priming into clinical practice.

Episodic memory deficits are frequently encountered following stroke. Rehabilitation of these deficits is often associated with short term effects that do not persist at follow up times. Neuromodulation tools acting on alterations of excitation/inhibition dynamics could be useful for rehabilitation of episodic memory. Prism adaptation with visual field deviation ipsilateral to the affected hemisphere can specifically modulate brain excitability and lead to improvement of cognitive deficits in post-stroke patients. Here we investigated whether prism adaptation followed by digital cognitive training could induce long term improvement of episodic memory deficits in stroke patients as compared with traditional rehabilitation.Sixty stroke patients were recruited for the study. Thirty patients were treated with prism adaptation combined with serious games targeting executive processes, with a ten days protocol (experimental group); thirty patients were treated with conventional rehabilitation (control group). Patients were tested with a battery of neuropsychological tests, including verbal and visual episodic memory tasks at four times: at baseline (T0); immediately after the end of the rehab protocol (T1); after 3 months (T2); after six months (T3).The main results showed a significant long term effect of the experimental treatment on both immediate and delayed recall phases of the visual episodic memory task. The effects were not linked to the affected hemisphere (right vs. left), nor to the hemorrhagic or ischemic type of stroke nor to the cortical or subcortical site of lesion.These findings show for the first time an improvement of long term memory in stroke patients following the use of a medical device combining prism adaptation and digital cognitive training, paving the way to novel rehabilitation techniques for cognitive deficits in stroke.

BackgroundHigh-Runner (HR) mice, selectively bred for increased voluntary wheel running behavior, exhibit heightened motivation to run. Exercise has been shown to influence hippocampal long-term potentiation (LTP) and memory, and is neuroprotective in several neurodegenerative diseases.ObjectiveThis study aimed to determine the impact of intense running in HR mice with wheel access on hippocampal LTP, compared to HR mice without wheels and non-selected control (C) mice with/without wheels. Additionally, we investigated the involvement of D1/D5 receptors and the dopamine transporter (DAT) in LTP modulation and examined levels of these proteins in HR and C mice.MethodsAdult female HR and C mice were individually housed with/without running wheels for at least two weeks. Hippocampal LTP of extracellular field excitatory postsynaptic potentials (fEPSPs) was measured in area CA1, and SKF-38393 (D1/D5 receptor agonist) and GBR 12909 (DAT inhibitor) were used to probe the role of D1/D5 receptors and DAT in LTP differences. Western blot analyses assessed D1/D5 receptor and DAT expression in the hippocampus, prefrontal cortex, and cerebellum.ResultsHR mice with wheel access showed significantly increased hippocampal LTP compared to those without wheels and to C mice with/without wheels. Treatment with SKF-38393 or GBR 12909 prevented the heightened LTP in HR mice with wheels, aligning it with levels in C mice. Hippocampal D1/D5 receptor levels were lower, and DAT levels were higher in HR mice compared to C mice. No significant changes were observed in other brain regions.ConclusionsThe increased hippocampal LTP seen in HR mice with wheel access may be related to alterations in dopaminergic synaptic transmission that underlie the neurophysiological basis of hyperactivity, motor disorders, and/or motivation.

BackgroundA better understanding of migraine pathophysiology through standardized methods could facilitate the development of more effective therapeutic approaches for migraine sufferers. However, neurophysiological studies with migraine sufferers present larger variability, as most contain only a single measurement.ObjectiveThis observational study aimed to compare the cortical and visual excitability of migraine sufferers, individuals with other types of headaches, and healthy participants in response to pattern-reversal visual stimulation.MethodsFifty-nine individuals were classified by a neurologist into the following groups: (i) migraineurs (n = 25); (ii) other types of headaches (n = 23); (iii) healthy (n = 11). Habituation during pattern-reversal visual stimulation was assessed by visual evoked potentials. Visual and motor cortex excitability were evaluated before and after pattern-reversal visual stimulation.ResultsWe found no intergroup differences in motor and visual excitability measures after pattern-reversal visual stimulation. Compared to the healthy group, migraineurs and individuals with other types of headaches displayed a reduction in phosphene threshold after pattern-reversal visual stimulation. Additionally, an increase in visual cortical excitability in these groups was also observed. Lastly, the habituation in individuals with migraines and other types of headaches was lower compared to healthy individuals. Therefore, the lack of habituation may not be exclusively associated with the pathophysiological mechanisms of migraine.ConclusionIndividuals who experience headaches, including migraineurs, have an increased visual cortical excitability in response to visual stimuli. This finding is promising for guiding future neurophysiological research to identify cortical biomarkers in migraineurs and in other types of headaches.

Objective: The aim of this study is to assess the motor outcomes of patients undergoing surgical neurolysis and to conduct a comprehensive review of existing literature to ascertain the efficacy and utility of this technique. Surgical neurolysis is a procedure designed to liberate an injured nerve from scar tissue or adjacent structure, thereby facilitating nerve regeneration in cases of brachial plexus neuropathy (BPN). Methods: This study presents a case series of patients diagnosed with BPN who underwent surgical neurolysis. The primary focus was on the clinical assessment of recovery using the British Medical Research Council motor grading scale (BMRC). Additionally, a comprehensive literature review was conducted to analyze motor recovery outcomes related to surgical neurolysis for BPN. 18 patients with BPN who underwent surgical neurolysis were included. Results: It was experienced a notable increase of 58% in muscle strength as assessed by the BMRC. The average preoperative state of 2.17 ± 1.15 improved significantly to a postoperative condition of 3.44 ± 1.34 (p = 0.003, d = 0.913) The systematic review identified 2298 relevant articles, out of which 8 articles published between 1995 and 2021 were selected for qualitative analysis, demonstrated that surgical neurolysis was associated with favorable motor recovery outcomes in 75.82% of the patients. Conclusions: Both the case series and the literature review reveal significant motor recovery following surgical neurolysis. It is crucial to conduct well-designed, adequately powered, randomized, and blinded clinical trials. Such studies will provide robust evidence to support or refute the utility of this approach in motor recovery.

High-definition transcranial direct current stimulation (HD-tDCS) is a promising approach for stroke rehabilitation, which may induce functional changes in the cortical sensorimotor areas to facilitate movement recovery. However, it lacks an objective measure that can indicate the effect of HD-tDCS on alteration of brain activity. Quantitative electroencephalography (qEEG) has shown promising results as an indicator of post-stroke functional recovery. Therefore, this study aims to determine whether qEEG metrics could serve as quantitative measures to assess alteration in brain activity induced by HD-tDCS. Resting state EEG was collected from stroke participants before and after (1) anodal HD-tDCS of the lesioned hemisphere, (2) cathodal stimulation of the non-lesioned hemisphere, and (3) sham. The average power spectrum was calculated using the Fast Fourier Transform for frequency bands alpha, beta, delta, and theta. In addition, delta-alpha ratio (DAR), Delta-alpha-beta-theta ratio (DTABR), and directional brain symmetry index (BSI) were also evaluated. We found that both anodal and cathodal stimulation significantly decreased the DAR and BSI over various frequency bands, which are associated with reduced motor impairments and improved nerve conduction velocity from the brain to muscles. This result indicates that qEEG metrics DAR and BSI could be quantitative indicators to assess alteration of brain activity induced by HD-tDCS in stroke rehabilitation. This would allow future development of EEG-based neurofeedback system to guide and evaluate the effect of HD-tDCS on improving movement-related brain function in stroke.

BackgroundThe excitability of the corticospinal tract (i.e., corticospinal excitability) is a valuable tool for assessing neurophysiology and the effectiveness of interventions in individuals with and without neurological and/or orthopaedic injuries. Corticospinal excitability is often measured with an input-output recruitment curve, which is produced by stimulating the motor cortex via transcranial magnetic stimulation (TMS) at several intensities and measuring the changes in the evoked responses. However, it is currently unclear if hysteresis in motor evoked potentials (MEPs) (i.e., changes in MEP amplitude due to the order of stimulus intensities) affects the resulting measure of excitability, particularly in lower extremity muscles.ObjectiveTo evaluate whether the order of stimulus intensity (ascending, descending, randomized) affects input-output recruitment curves measured in the lower extremity muscles.MethodsRecruitment curves were produced in neurologically intact individuals by stimulating the primary motor cortex at 70% to 140% of active motor threshold in 10% increments. We examined three stimulus intensity ordering paradigms: ascending (70$\to$140), descending (140$\to$70), and randomized. We measured MEPs of the quadriceps and the antagonistic hamstring muscles using surface electromyography in addition to quadriceps motor evoked torque. We computed the area under the recruitment curve (AUC) of the raw and normalized motor evoked responses and used classical and Bayesian inference methods to comprehensively evaluate hysteresis in MEPs.ResultsClassical hypothesis testing revealed no significant main effects of stimulus order. Bayesian analyses also confirmed that the null model was more favored than the main effects model.ConclusionsCorticospinal excitability of the quadriceps and antagonistic hamstring muscles were not influenced by stimulus intensity order. Any of the three approaches (ascending, descending, randomized) may be used when measuring recruitment curves for the quadriceps and hamstring muscles.