It takes two: noninvasive brain stimulation combined with neurorehabilitation

Symptom Persistence Relates to Volume and Asymmetry of the Limbic System after Mild Traumatic Brain Injury

Background: Persistent symptoms have been reported in up to 50% of the 27 million people with mild traumatic brain injuries (mTBI) every year. MRI findings are currently limited by low diagnostic and prognostic sensitivities, constraining the value of imaging in the stratification of patients following mTBI. Limbic system structures are promising brain regions in offering prognostic factors for symptom persistence following mTBI. The objective of this study was to associate volume and symmetry of limbic system structures with the presence and persistence of common symptoms in patients with mTBI. Methods: This study focused on 524 adults (aged 18-82), 58% female, with 82% injured in motor vehicle accidents and 28% reporting loss of consciousness (LOC). Magnetic resonance imaging (MRI) data included a sagittal 3D T1-weighted sequence with 1.2 mm slice thickness, with voxel sizes of 0.93 mm × 0.93 mm × 1.2 mm, obtained a median of 156 days after injury. Symptom diagnosis and persistence were collected retrospectively from patient medical records. Intracranial volume-adjusted regional volumes per side utilizing automated volumetric analysis (NeuroQuant®) were used to calculate total volume, laterality index, and side-independent asymmetry. Covariates included age, sex, LOC, and days from injury. Limbic volumetrics did not relate to symptom presentation, except the (-) association between headache presence and thalamus volume (adjusted odds ratio = 0.51, 95% confidence interval = 0.32, 0.85). Headache, balance problems, anxiety, and depression persistence was (-) associated with thalamus volume (hazard ratio (HR) 1.25 to 1.94). Longer persistence of balance problems was associated with (-) lateral orbitofrontal cortex volume (HR = 1.33) and (+) asymmetry of the hippocampus (HR = 0.27). Persistence of cognitive deficits was associated with (+) asymmetry in the caudal anterior cingulate (HR = 0.67). Depression persistence was associated with (+) asymmetry in the isthmus of the cingulate gyrus (HR = 5.39). Persistence of anxiety was associated with (-) volume of the parahippocampal gyrus (HR = 1.67), orbitofrontal cortex (HR > 1.97), and right-biased laterality of the entorhinal cortex (HR = 0.52). Conclusions: Relative volume and asymmetry of the limbic system structures in patients with mTBI are associated with the persistence of symptoms, particularly anxiety. The conclusions of this study are limited by the absence of a reference group with no mTBI.

Disorders of Consciousness

This article reviews the definition, assessment, neuroimaging, treatment, and rehabilitation for disorders of consciousness after an acquired brain injury. It also explores special considerations and new neuromodulation treatment options.

The Art of Bioimmunogenomics (BIGs) 5.0 in CAR-T Cell Therapy for Lymphoma Management

Purpose

Lymphoma, the most predominant neoplastic disorder, is divided into Hodgkin and Non-Hodgkin Lymphoma classifications. Immunotherapeutic modalities have emerged as essential methodologies in combating lymphoid malignancies. Chimeric Antigen Receptor (CAR) T cells exhibit promising responses in chemotherapy-resistant B-cell non-Hodgkin lymphoma cases.

Methods

This comprehensive review delineates the advancement of CAR-T cell therapy as an immunotherapeutic instrument, the selection of lymphoma antigens for CAR-T cell targeting, and the conceptualization, synthesis, and deployment of CAR-T cells. Furthermore, it encompasses the advantages and disadvantages of CAR-T cell therapy and the prospective horizons of CAR-T cells from a computational research perspective. In order to improve the design and functionality of artificial CARs, there is a need for TCR recognition investigation, followed by the implementation of a quality surveillance methodology.

Results

Various lymphoma antigens are amenable to CAR-T cell targeting, such as CD19, CD20, CD22, CD30, the kappa light chain, and ROR1. A notable merit of CAR-T cell therapy is the augmentation of the immune system's capacity to generate tumoricidal activity in patients exhibiting chemotherapy-resistant lymphoma. Nevertheless, it also introduces manufacturing impediments that are laborious, technologically demanding, and financially burdensome. Physical, physicochemical, and physiological limitations further exacerbate the challenge of treating solid neoplasms with CAR-T cells.

Conclusion

While the efficacy and safety of CAR-T cell immunotherapy remain subjects of fervent investigation, the promise of this cutting-edge technology offers valuable insights for the future evolution of lymphoma treatment management approaches. Moreover, CAR-T cell therapies potentially benefit patients, motivating regulatory bodies to foster international collaboration.

Can cerebellar theta-burst stimulation improve balance function and gait in stroke patients? A randomized controlled trial

BACKGROUND

The cerebellum is a key structure involved in balance and motor control, and has become a new stimulation target in brain regulation technology. Interference theta-burst simulation (iTBS) is a novel simulation mode of repetitive transcranial magnetic simulation. However, the impact of cerebellar iTBS on balance function and gait in stroke patients is still unknown.

AIM

The aim of this study was to determine whether cerebellar iTBS can improve function, particularly balance and gait, in patients with post-stroke hemiplegia.

DESIGN

This study is a randomized, double-blind, sham controlled clinical trial.

SETTING

The study was carried out at the Department of Rehabilitation Medicine in a general hospital.

POPULATION

Patients with stroke with first unilateral lesions were enrolled in the study.

METHODS

Thirty-six patients were randomly assigned to the cerebellar iTBS group or sham stimulation group. The cerebellar iTBS or pseudo stimulation site is the ipsilateral cerebellum on the paralyzed side, which is completed just before daily physical therapy. The study was conducted five times a week for two consecutive weeks. All patients were assessed before the intervention (T0) and at the end of 2 weeks of treatment (T1), respectively. The primary outcome was the Berg Balance Scale (BBS), while secondary outcome measures included the Fugl Meyer Lower Limb Assessment Scale (FMA-LE), timed up and go (TUG), Barthel Index (BI), and gait analysis.

RESULTS

After 2 weeks of intervention, the BBS, FMA-LE, TUG, and BI score in both the iTBS group and the sham group were significantly improved compared to the baseline (all P<0.05). Also, there was a significant gait parameter improvement including the cadence, stride length, velocity, step length compared to the baseline (P<0.05) in the iTBS group, but only significant improvement in cadence was identified in the sham group (P<0.05). Intergroup comparison showed that the BBS (P<0.001), FMA-LE (P<0.001), and BI (P=0.002) in the iTBS group were significantly higher than those in the sham group, and the TUG in the iTBS was significantly lower than that in the sham group (P=0.002). In addition, there were significant differences in cadence (P=0.029), strip length (P=0.046), gain velocity (P=0.002), and step length of affected lower limb (P=0.024) between the iTBS group and the sham iTBS group.

CONCLUSIONS

Physical therapy is able to improve the functional recovery in hemiplegic patients after stroke, but the cerebellar iTBS can facilitate and accelerate the recovery, particularly the balance function and gait. Cerebellar iTBS could be an efficient and facilitative treatment for patients with stroke.

CLINICAL REHABILITATION IMPACT

Cerebellar iTBS provides a convenient and efficient treatment modality for functional recovery of patients with stroke, especially balance function and gait.

Safety and efficacy of non-invasive brain stimulation for the upper extremities in children with cerebral palsy: A systematic review

AIM

To evaluate available evidence examining safety and efficacy of non-invasive brain stimulation (NIBS) on upper extremity outcomes in children with cerebral palsy (CP).

METHOD

We electronically searched 12 sources up to May 2023 using JBI and Cochrane guidelines. Two reviewers selected articles with predetermined eligibility criteria, conducted data extraction, and assessed risk of bias using the Cochrane Risk of Bias criteria.

RESULTS

Nineteen studies were included: eight using repetitive transcranial magnetic stimulation (rTMS) and 11 using transcranial direct current stimulation (tDCS). Moderate certainty evidence supports the safety of rTMS and tDCS for children with CP. Very low to moderate certainty evidence suggests that rTMS and tDCS result in little to no difference in upper extremity outcomes.

INTERPRETATION

Evidence indicates that NIBS is a safe and feasible intervention to target upper extremity outcomes in children with CP, although it also indicates little to no significant impact on upper extremity outcomes. These findings are discussed in relation to the heterogeneous participants' characteristics and stimulation parameters. Larger studies of high methodological quality are required to inform future research and protocols for NIBS.

Noninvasive cerebellar stimulation and behavioral interventions: A crucial synergy for post-stroke motor rehabilitation

BACKGROUND

Improvement of functional movements after supratentorial stroke occurs through spontaneous biological recovery and training-induced reorganization of remnant neural networks. The cerebellum, through its connectivity with the cortex, brainstem and spinal cord, is actively engaged in both recovery and reorganization processes within the cognitive and sensorimotor systems. Noninvasive cerebellar stimulation (NiCBS) offers a safe, clinically feasible and potentially effective way to modulate the excitability of spared neural networks and promote movement recovery after supratentorial stroke. NiCBS modulates cerebellar connectivity to the cerebral cortex and brainstem, as well as influences the sensorimotor and frontoparietal networks.

OBJECTIVE

Our objective was twofold: (a) to conduct a scoping review of studies that employed NiCBS to influence motor recovery and learning in individuals with stroke, and (b) to present a theory-driven framework to inform the use of NiCBS to target distinct stroke-related deficits.

METHODS

A scoping review of current research up to August 2023 was conducted to determine the effect size of NiCBS effect on movement recovery of upper extremity function, balance, walking and motor learning in humans with stroke.

RESULTS

Calculated effect sizes were moderate to high, offering promise for improving upper extremity, balance and walking outcomes after stroke. We present a conceptual framework that capitalizes on cognitive-motor specialization of the cerebellum to formulate a synergy between NiCBS and behavioral interventions to target specific movement deficits.

CONCLUSION

NiCBS enhances recovery of upper extremity impairments, balance and walking after stroke. Physiologically-informed synergies between NiCBS and behavioral interventions have the potential to enhance recovery. Finally, we propose future directions in neurophysiological, behavioral, and clinical research to move NiCBS through the translational pipeline and augment motor recovery after stroke.

Neuromodulation of Executive Dysfunction in Patients with Acute Stroke Using Transcranial Direct Current Stimulation: Study Protocol for a Triple-Blind, Randomized Sham-Controlled Trial

Research on the benefits of non-invasive brain stimulation in stroke patients to improve executive functions is scarce. The objective of this study was to investigate the effectiveness of transcranial direct current stimulation (tDCS) in combination with cognitive training for the rehabilitation of executive functions in acute and subacute stroke patients as well as to explore the underlying physiological mechanisms. A triple-blinded, randomized-controlled clinical trial will be conducted involving 60 stroke patients with frontal or basal ganglia lesions and a Montreal Cognitive Assessment (MoCA) score less than 26. Participants will be randomly assigned to receive active tDCS (anode over the left dorsolateral prefrontal cortex, cathode at the right supraorbital region, 20 min at 2 mA) or sham tDCS in a 1:1 ratio for 10 sessions, followed by targeted executive function training. The primary efficacy outcome will be the MoCA score, while secondary outcomes will include the five-digit test (inhibitory control), the Digit Span Task (working memory), the abbreviated version of the Wisconsin Card Sorting test (cognitive flexibility), modified Rankin scale (functional state), Beck-II depression inventory, apathy evaluation scale, and the WHOQOL-BREF (quality of life), assessed immediately after the intervention and at 1, 3, 6, and 12 months post-intervention. Additionally, resting-state functional connectivity and blood biomarkers, such as neurotrophins, growth factors, and inflammatory molecules, will be evaluated before and after the intervention. This study will contribute to the investigation of the efficacy of tDCS in rehabilitating executive functions in acute and subacute stroke patients. The multidimensional approach utilized in this study, which includes analysis of resting-state connectivity and neuroplasticity-related blood biomarkers, is expected to provide insights into the underlying brain mechanisms involved in the rehabilitation of dysexecutive syndrome.

Repetitive transcranial magnetic stimulation promotes neurological functional recovery in rats with traumatic brain injury by upregulating synaptic plasticity-related proteins

Studies have shown that repetitive transcranial magnetic stimulation (rTMS) can enhance synaptic plasticity and improve neurological dysfunction. However, the mechanism through which rTMS can improve moderate traumatic brain injury remains poorly understood. In this study, we established rat models of moderate traumatic brain injury using Feeney’s weight-dropping method and treated them using rTMS. To help determine the mechanism of action, we measured levels of several important brain activity-related proteins and their mRNA. On the injured side of the brain, we found that rTMS increased the protein levels and mRNA expression of brain-derived neurotrophic factor, tropomyosin receptor kinase B, N-methyl-D-aspartic acid receptor 1, and phosphorylated cAMP response element binding protein, which are closely associated with the occurrence of long-term potentiation. rTMS also partially reversed the loss of synaptophysin after injury and promoted the remodeling of synaptic ultrastructure. These findings suggest that upregulation of synaptic plasticity-related protein expression is the mechanism through which rTMS promotes neurological function recovery after moderate traumatic brain injury.

A Pilot Study of Intensive Locomotor-Related Skill Training and Transcranial Direct Current Stimulation in Chronic Spinal Cord Injury

BACKGROUND AND PURPOSE

Improved walking function is a priority among persons with motor-incomplete spinal cord injury (PwMISCI). Accessibility and cost limit long-term participation in locomotor training offered in specialized centers. Intensive motor training that facilitates neuroplastic mechanisms that support skill learning and can be implemented in the home/community may be advantageous for promoting long-term restoration of walking function. Additionally, increasing corticospinal drive via transcranial direct current stimulation (tDCS) may enhance training effects. In this pilot study, we investigated whether a moderate-intensity motor skill training (MST) circuit improved walking function in PwMISCI and whether augmenting training with tDCS influenced outcomes.

METHODS

Twenty-five adults (chronic, motor-incomplete spinal cord injury) were randomized to a 3-day intervention of a locomotor-related MST circuit and concurrent application of sham tDCS (MST+tDCS sham ) or active tDCS (MST+tDCS). The primary outcome was overground walking speed. Secondary outcomes included walking distance, cadence, stride length, and step symmetry index (SI).

RESULTS

Analyses revealed significant effects of the MST circuit on walking speed, walking distance, cadence, and bilateral stride length but no effect on interlimb SI. No significant between-groups differences were observed. Post hoc analyses revealed within-groups change in walking speed (ΔM = 0.13 m/s, SD = 0.13) that app-roached the minimally clinically important difference of 0.15 m/s.

DISCUSSION AND CONCLUSIONS

Brief, intensive MST involving locomotor-related activities significantly increased walking speed, walking distance, and spatiotemporal measures in PwMISCI. Significant additive effects of tDCS were not observed; however, participation in only 3 days of MST was associated with changes in walking speed that were comparable to longer locomotor training studies.Video Abstract available for more insights from the authors (see the Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A386 ).

Non-invasive brain stimulation associated mirror therapy for upper-limb rehabilitation after stroke: Systematic review and meta-analysis of randomized clinical trials

Background

Non-invasive brain stimulation (NIBS) techniques and mirror therapy (MT) are promising rehabilitation measures for stroke. While the combination of MT and NIBS has been employed for post-stroke upper limb motor functional rehabilitation, its effectiveness has not been examined.

Objective

This study aimed to evaluate the effectiveness of combined MT and NIBS in the recovery of upper limb motor function in stroke patients.

Methods

The search was carried out in PubMed, EMBASE, Cochrane Library, Web of Science, Science Direct, CNKI, WANFANG and VIP until December 2021. Randomized clinical trials (RCTs) comparing MT or NIBS alone with the combination of NIBS and MT in improving upper extremity motor recovery after stroke were selected. A meta-analysis was performed to calculate the mean differences (MD) or the standard mean differences (SMD) and 95% confidence intervals (CI) with random-effect models. Subgroup analyses were also conducted according to the types of control group, the types of NIBS, stimulation timing and phase poststroke.

Results

A total of 12 articles, including 17 studies with 628 patients, were reviewed in the meta-analysis. In comparison with MT or NIBS alone, the combined group significantly improved body structure and function (MD = 5.97; 95% CI: 5.01–6.93; P < 0.05), activity levels (SMD = 0.82; 95% CI 0.61–1.02; P < 0.05). For cortical excitability, the motor evoked potential cortical latency (SMD = −1.05; 95% CI:−1.57–−0.52; P < 0.05) and the central motor conduction time (SMD=-1.31 95% CI:−2.02-−0.61; P < 0.05) of the combined group were significantly shortened. A non-significant homogeneous summary effect size was found for MEP amplitude (SMD = 0.47; 95%CI = −0.29 to 1.23; P = 0.23). Subgroup analysis showed that there is an interaction between the stimulation sequence and the combined treatment effect.

Conclusion

In this meta-analysis of randomized clinical trials, in comparison to the control groups, MT combined with NIBS promoted the recovery of upper extremity motor function after stroke, which was reflected in the analysis of body structure and function, activity levels, and cortical excitability.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42022304455.

fNIRS-based adaptive visuomotor task improves sensorimotor cortical activation

OBJECTIVE

Investigating how to promote the functional activation of the central sensorimotor system is an important goal in the neurorehabilitation research domain. We aim to validate the effectiveness of facilitating cortical excitability using a closed-loop visuomotor task, in which the task difficulty is adaptively adjusted based on an individual's sensorimotor cortical activation.

APPROACH

We developed a novel visuomotor task, in which subjects moved a handle of a haptic device along a specific path while exerting a constant force against a virtual surface under visual feedback. The difficulty levels of the task were adapted with the aim of increasing the activation of sensorimotor areas, measured non-invasively by functional near-infrared spectroscopy. The changes in brain activation of the bilateral prefrontal cortex, sensorimotor cortex, and the occipital cortex obtained during the adaptive visuomotor task (adaptive group), were compared to the brain activation pattern elicited by the same duration of task with random difficulties in a control group.

MAIN RESULTS

During one intervention session, the adaptive group showed significantly increased activation in the bilateral sensorimotor cortex, also enhanced effective connectivity between the prefrontal and sensorimotor areas compared to the control group.

SIGNIFICANCE

Our findings demonstrated that the fNIRS-based adaptive visuomotor task with high ecological validity can facilitate the neural activity in sensorimotor areas and thus has the potential to improve hand motor functions.

Walking and Balance Outcomes Are Improved Following Brief Intensive Locomotor Skill Training but Are Not Augmented by Transcranial Direct Current Stimulation in Persons With Chronic Spinal Cord Injury

Motor training to improve walking and balance function is a common aspect of rehabilitation following motor-incomplete spinal cord injury (MISCI). Evidence suggests that moderate- to high-intensity exercise facilitates neuroplastic mechanisms that support motor skill acquisition and learning. Furthermore, enhancing corticospinal drive via transcranial direct current stimulation (tDCS) may augment the effects of motor training. In this pilot study, we investigated whether a brief moderate-intensity locomotor-related motor skill training (MST) circuit, with and without tDCS, improved walking and balance outcomes in persons with MISCI. In addition, we examined potential differences between within-day (online) and between-day (offline) effects of MST. Twenty-six adults with chronic MISCI, who had some walking ability, were enrolled in a 5-day double-blind, randomized study with a 3-day intervention period. Participants were assigned to an intensive locomotor MST circuit and concurrent application of either sham tDCS (MST+tDCS_sham) or active tDCS (MST+tDCS). The primary outcome was overground walking speed measured during the 10-meter walk test. Secondary outcomes included spatiotemporal gait characteristics (cadence and stride length), peak trailing limb angle (TLA), intralimb coordination (ACC), the Berg Balance Scale (BBS), and the Falls Efficacy Scale-International (FES-I) questionnaire. Analyses revealed a significant effect of the MST circuit, with improvements in walking speed, cadence, bilateral stride length, stronger limb TLA, weaker limb ACC, BBS, and FES-I observed in both the MST+tDCS_sham and MST+tDCS groups. No differences in outcomes were observed between groups. Between-day change accounted for a greater percentage of the overall change in walking outcomes. In persons with MISCI, brief intensive MST involving a circuit of ballistic, cyclic locomotor-related skill activities improved walking outcomes, and selected strength and balance outcomes; however, concurrent application of tDCS did not further enhance the effects of MST.

Effects of combining two techniques of non-invasive brain stimulation in subacute stroke patients: a pilot study

Background

Strokes have recently become a leading cause of disability among Thai people. Non-invasive brain stimulation (NIBS) seems to give promising results in stroke recovery when combined with standard rehabilitation programs.

Objective

To evaluate the combined effect of low-frequency repetitive transcranial magnetic stimulation (rTMS) and cathodal transcranial direct current stimulation (tDCS) over the non-lesional primary motor cortex on upper limb motor recovery in patients with subacute stroke. No reports of a combination of these two techniques of NIBS were found in the relevant literature.

Methods

This pilot study was a double-blinded, randomized controlled trial of ten patients with subacute stroke admitted to the Rehabilitation Medicine Inpatient Unit, Maharaj Nakorn Chiang Mai Hospital, Chiang Mai University. They were randomized into two groups: five in an active and five in a sham intervention group. Fugl-Meyer’s upper extremity motor score (FMA-UE) and Wolf Motor Function Test (WMFT) were used to assess motor recovery at baseline, immediately, and 1 week after stimulation.

Results

A two-way repeated ANOVA (mixed design) showed a significant improvement in FMA-UE scores in the active intervention group both immediately and 1 week after stimulation in comparison to the baseline, [time, F (2, 16) = 27.44, p < 0.001, time x group interaction, F (2, 16) = 13.29, p < 0.001]. Despite no statistical significance, a trend toward higher WMFT scores was shown in the active intervention group.

Conclusions

A single session of low-frequency rTMS and cathodal tDCS over the non-lesional primary motor cortex may enhance upper limb motor recovery in patients with subacute stroke.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02607-3.

Noninvasive brain stimulation to augment language therapy for poststroke aphasia

Behavioral language treatment approaches represent the standard of care for persons with aphasia (PWA), but the benefits of these treatments are variable. Moreover, due to the logistic and financial limitations on the amount of behavioral therapy available to patients, it is often infeasible for PWA to receive behavioral interventions with the level of frequency, intensity, or duration that would provide significant and lasting benefit, underscoring the need for novel, effective treatment approaches. Noninvasive brain stimulation (NIBS) techniques, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), have emerged as promising neurally-based tools to enhance language abilities for PWA following stroke. This chapter first provides an overview of the methods and physiologic basis motivating the use of NIBS to enhance aphasia recovery followed by a selective review of the growing evidence of its potential as a novel therapeutic tool. Subsequent sections discuss some of the principles that may prove most useful in guiding and optimizing the effects of NIBS on aphasia recovery, focusing on how the functional state of the brain at the time of stimulation interacts with the behavioral aftereffects of neuromodulation. We conclude with a discussion of current challenges and future directions for NIBS in aphasia treatment.

Experimental Protocol to Test Explicit Motor Learning–Cerebellar Theta Burst Stimulation

Implicit and explicit motor learning processes work interactively in everyday life to promote the creation of highly automatized motor behaviors. The cerebellum is crucial for motor sequence learning and adaptation, as it contributes to the error correction and to sensorimotor integration of on-going actions. A non-invasive cerebellar stimulation has been demonstrated to modulate implicit motor learning and adaptation. The present study aimed to explore the potential role of cerebellar theta burst stimulation (TBS) in modulating explicit motor learning and adaptation, in healthy subjects. Cerebellar TBS will be applied immediately before the learning phase of a computerized task based on a modified Serial Reaction Time Task (SRTT) paradigm. Here, we present a study protocol aimed at evaluating the behavioral effects of continuous (cTBS), intermittent TBS (iTBS), or sham Theta Burst Stimulation (TBS) on four different conditions: learning, adaptation, delayed recall and re-adaptation of SRTT. We are confident to find modulation of SRTT performance induced by cerebellar TBS, in particular, processing acceleration and reduction of error in all the conditions induced by cerebellar iTBS, as already known for implicit processes. On the other hand, we expect that cerebellar cTBS could induce opposite effects. Results from this protocol are supposed to advance the knowledge about the role of non-invasive cerebellar modulation in neurorehabilitation, providing clinicians with useful data for further exploiting this technique in different clinical conditions.

From Research to Practice: Toward the Examination of Combined Interventions for Autism Spectrum Disorders

The use of biological (i.e., medications) in conjunction with applied behavior analysis is relatively common among people with ASD, yet research examining its benefit is scarce. This paper provides a brief overview of the existing literature on the combined interventions, including promising developments, and examines the existing barriers that hinder research in this area, including the heavy reliance on RCTs. Recommendations for possible solutions, including the creation of health homes, are provided in order to move toward a more integrated approach.

The Ties That Bind: Aberrant Plasticity and Networks Dysfunction in Movement Disorders-Implications for Rehabilitation

Background: Movement disorders encompass various conditions affecting the nervous system. The pathological processes underlying movement disorders lead to aberrant synaptic plastic changes, which in turn alter the functioning of large-scale brain networks. Therefore, clinical phenomenology does not only entail motor symptoms but also cognitive and motivational disturbances. The result is the disruption of motor learning and motor behavior. Due to this complexity, the responsiveness to standard therapies could be disappointing. Specific forms of rehabilitation entailing goal-based practice, aerobic training, and the use of noninvasive brain stimulation techniques could "restore" neuroplasticity at motor-cognitive circuitries, leading to clinical gains. This is probably associated with modulations occurring at both molecular (synaptic) and circuitry levels (networks). Several gaps remain in our understanding of the relationships among plasticity and neural networks and how neurorehabilitation could promote clinical gains is still unclear. Purposes: In this review, we outline first the networks involved in motor learning and behavior and analyze which mechanisms link the pathological synaptic plastic changes with these networks' disruption in movement disorders. Therefore, we provide theoretical and practical bases to be applied for treatment in rehabilitation.

Cerebellar Theta-Burst Stimulation Combined With Physiotherapy in Subacute and Chronic Stroke Patients: A Pilot Randomized Controlled Trial

BACKGROUND

Intermittent theta-burst stimulation (iTBS) has been suggested to improve poststroke rehabilitation. The cerebellum is considered crucial for motor control. However, the effects of cerebellar iTBS with routine physical therapy on balance and motor recovery in subacute and chronic stroke patients have not been explored.

OBJECTIVE

To measure the short-term effects of cerebellar iTBS with physiotherapy on the balance and functional outcomes in subacute and chronic stroke patients with hemiparesis.

METHODS

Thirty hemiparetic patients were recruited for this randomized, double-blinded, sham-controlled trial, and randomized into either the treatment or sham group. Both groups participated in physiotherapy 5 times per week for 2 weeks, and cerebellar iTBS or sham iTBS was performed daily, immediately before physiotherapy. The primary outcome was the Berg balance scale (BBS) score. Secondary outcomes included the trunk impairment scale (TIS) score, Fugl-Meyer assessment scale score for lower extremities (FMA-LE), Barthel index (BI), and corticospinal excitability, as measured by transcranial magnetic stimulation. The outcomes were measured before and 1 week and 2 weeks after the intervention.

RESULTS

Compared with those at baseline, significant increases were identified in all clinical scores (BBS, TIS, FMA-LE, and BI) in both groups after the 2-week intervention. The BBS and TIS scores improved more in the iTBS group than in the sham group.

CONCLUSIONS

Cerebellar iTBS with physiotherapy promotes balance and motor recovery in poststroke patients. Therefore, this method can be used in low-cost, fast, and efficient protocols for stroke rehabilitation (Chinese Clinical Trial Registry: ChiCTR1900026450).

Neurostimulation and Reach-to-Grasp Function Recovery Following Acquired Brain Injury: Insight From Pre-clinical Rodent Models and Human Applications

Reach-to-grasp is an evolutionarily conserved motor function that is adversely impacted following stroke and traumatic brain injury (TBI). Non-invasive brain stimulation (NIBS) methods, such as transcranial magnetic stimulation and transcranial direct current stimulation, are promising tools that could enhance functional recovery of reach-to-grasp post-brain injury. Though the rodent literature provides a causal understanding of post-injury recovery mechanisms, it has had a limited impact on NIBS protocols in human research. The high degree of homology in reach-to-grasp circuitry between humans and rodents further implies that the application of NIBS to brain injury could be better informed by findings from pre-clinical rodent models and neurorehabilitation research. Here, we provide an overview of the advantages and limitations of using rodent models to advance our current understanding of human reach-to-grasp function, cortical circuitry, and reorganization. We propose that a cross-species comparison of reach-to-grasp recovery could provide a mechanistic framework for clinically efficacious NIBS treatments that could elicit better functional outcomes for patients.

Timing-dependent effects of transcranial direct current stimulation with mirror therapy on daily function and motor control in chronic stroke: a randomized controlled pilot study

Background

The timing of transcranial direct current stimulation (tDCS) with neurorehabilitation interventions may affect its modulatory effects. Motor function has been reported to be modulated by the timing of tDCS; however, whether the timing of tDCS would also affect restoration of daily function and upper extremity motor control with neurorehabilitation in stroke patients remains largely unexplored. Mirror therapy (MT) is a potentially effective neurorehabilitation approach for improving paretic arm function in stroke patients. This study aimed to determine whether the timing of tDCS with MT would influence treatment effects on daily function, motor function and motor control in individuals with chronic stroke.

Methods

This study was a double-blinded randomized controlled trial. Twenty-eight individuals with chronic stroke received one of the following three interventions: (1) sequentially combined tDCS with MT (SEQ), (2) concurrently combined tDCS with MT (CON), and (3) sham tDCS with MT (SHAM). Participants received interventions for 90 min/day, 5 days/week for 4 weeks. Daily function was assessed using the Nottingham Extended Activities of Daily Living Scale. Upper extremity motor function was assessed using the Fugl-Meyer Assessment Scale. Upper extremity motor control was evaluated using movement kinematic assessments.

Results

There were significant differences in daily function between the three groups. The SEQ group had greater improvement in daily function than the CON and SHAM groups. Kinematic analyses showed that movement time of the paretic hand significantly reduced in the SEQ group after interventions. All three groups had significant improvement in motor function from pre-intervention to post-intervention.

Conclusion

The timing of tDCS with MT may influence restoration of daily function and movement efficiency of the paretic hand in chronic stroke patients. Sequentially applying tDCS prior to MT seems to be advantageous for enhancing daily function and hand movement control, and may be considered as a potentially useful strategy in future clinical application.

Trial registration

ClinicalTrials.gov Identifier: NCT02827864. Registered on 29th June, 2016.

Effects of Long-Term Paired Associative Stimulation on Strength of Leg Muscles and Walking in Chronic Tetraplegia: A Proof-of-Concept Pilot Study

Recovery of lower-limb function after spinal cord injury (SCI) is dependent on the extent of remaining neural transmission in the corticospinal pathway. The aim of this proof-of-concept pilot study was to explore the effects of long-term paired associative stimulation (PAS) on leg muscle strength and walking in people with SCI. Five individuals with traumatic incomplete chronic tetraplegia (>34 months post-injury, motor incomplete, 3 females, mean age 60 years) with no contraindications to transcranial magnetic stimulation (TMS) received PAS to one or both legs for 2 months (28 sessions in total, 5 times a week for the first 2 weeks and 3 times a week thereafter). The participants were evaluated with the Manual Muscle Test (MMT), AIS motor and sensory examination, Modified Asworth Scale (MAS), and the Spinal Cord Independence Measure (SCIM) prior to the intervention, after 1 and 2 months of PAS, and after a 1-month follow-up. The study was registered at clinicaltrials.gov (NCT03459885). During the intervention, MMT scores and AIS motor scores increased significantly (p = 0.014 and p = 0.033, respectively). Improvements were stable in follow-up. AIS sensory scores, MAS, and SCIM were not modified significantly. MMT score prior to intervention was a good predictor of changes in walking speed (Radj2 = 0.962). The results of this proof-of-concept pilot study justify a larger trial on the effect of long-term PAS on leg muscle strength and walking in people with chronic incomplete SCI.

Evaluating the effects of tDCS in stroke patients using functional outcomes: a systematic review

Background and purpose: Transcranial direct current stimulation (tDCS) has been extensively studied over the past 20 years to promote functional motor recovery after stroke. However, tDCS clinical relevance still needs to be determined. The present systematic review aims to determine whether tDCS applied to the primary motor cortex (M1) in stroke patients can have a positive effect on functional motor outcomes.Materials and methods: Two databases (Medline & Scopus) were searched for randomized, double-blinded, sham-controlled trials pertaining to the use of M1 tDCS on cerebral stroke patients, and its effects on validated functional motor outcomes. When data were provided, effect sizes were calculated. PROSPERO registration number: CRD42018108157Results: 46 studies (n = 1291 patients) met inclusion criteria. Overall study quality was good (7.69/10 on the PEDro scale). Over half (56.5%) the studies were on chronic stroke patients. There seemed to be a certain pattern of recurring parameters, but tDCS protocols still remain heterogeneous. Overall results were positive (71.7% of studies found that tDCS has positive results on functional motor outcomes). Effect-sizes ranged from 0 to 1.33. No severe adverse events were reported.Conclusion: Despite heterogeneous stimulation parameters, outcomes and patient demographics, tDCS seems to be complementary to classical and novel rehabilitation approaches. With minimal adverse effects (if screening parameters are respected), none of which were serious, and a high potential to improve recovery when using optimal parameters (i.e.: 20 min of stimulation, at 2 mA with 25 or 35cm² electrodes that are regularly humidified), tDCS could potentially be ready for clinical applications.Implications for RehabilitationtDCS could potentially be ready for clinical application.Evidence of very low to very high quality is available on the effectiveness of tDCS to improve motor control following stroke.This should with caution be focused on the primary motor cortex.

Differential Effects of Transcranial Direct Current Stimulation (tDCS) Depending on Previous Musical Training

Previous studies have shown that transcranial direct current stimulation (tDCS) facilitates motor performance, but individual differences such as baseline performance seem to influence this effect. Accordingly, musicians offer an inter-individual differences model due to anatomical and functional variances displayed among the motor cortex regions. The aim of the present work was to study if the baseline motor skill predicts whether tDCS can enhance motor learning. For that objective, we administered anodal (n = 20) or sham (n = 20) tDCS on the right primary motor cortex region of 40 right-handed healthy participants, who were divided into four groups: musicians (tDCS/sham) and non-musicians (tDCS/sham). We measured the skill index (SI) presented in the sequential finger-tapping task (SEQTAP) at baseline, during three 20 min/2 mA stimulation sessions, and in follow-up tests after 20 min and 8 days. Depending on the normality of the data distribution, statistical differences were estimated by ANOVA and Bonferroni post hoc test or Kruskal-Wallis and U Mann-Whitney. Results showed that musicians scored higher in baseline performance than non-musicians. The non-musicians who received tDCS scored higher than the sham group in the first and second stimulation session. This effect was extended to the 20 min and 8 days follow-up test. In musicians, there was no effect of tDCS. The present method seems to be suitable for the achievement of positive and consolidated tDCS effects on motor learning in inexperienced participants, but not in musicians. These data may have an implication for the rehabilitation of motor impairments, contributing to more individualized stimulation protocols.

Multifractality, Interactivity, and the Adaptive Capacity of the Human Movement System: A Perspective for Advancing the Conceptual Basis of Neurologic Physical Therapy

BACKGROUND AND PURPOSE

Physical therapists seek to optimize movement as a means of reducing disability and improving health. The short-term effects of interventions designed to optimize movement ultimately are intended to be adapted for use across various future patterns of behavior, in potentially unpredictable ways, with varying frequency, and in the context of multiple tasks and environmental conditions. In this perspective article, we review and discuss the implications of recent evidence that optimal movement variability, which previously had been associated with adaptable motor behavior, contains a specific complex nonlinear feature known as "multifractality."

SUMMARY OF KEY POINTS

Multifractal movement fluctuation patterns reflect robust physiologic interactivity occurring within the movement system across multiple time scales. Such patterns provide conceptual support for the idea that patterns of motor behavior occurring in the moment are inextricably linked in complex, physiologic ways to patterns of motor behavior occurring over much longer periods. The human movement system appears to be particularly tuned to multifractal fluctuation patterns and exhibits the ability to reorganize its output in response to external stimulation embedded with multifractal features.

RECOMMENDATIONS FOR CLINICAL PRACTICE

As a fundamental feature of human movement, multifractality opens new avenues for conceptualizing the link between physiologic interactivity and adaptive capacity. Preliminary evidence supporting the positive influence of multifractal rhythmic auditory stimulation on the gait patterns of individuals with Parkinson disease is used to illustrate how physical therapy interventions might be devised to specifically target the adaptive capacity of the human movement system.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A183).

Minute Pulsed Electromagnetic Neurostimulation for Mixed Trauma Syndromes

Research regarding noninvasive brain stimulation technologies for the treatment of mild traumatic brain injury (mTBI), posttraumatic stress disorder (PTSD), and mixed (mTBI/PTSD) trauma syndromes has been increasing exponentially. Technologies with the greatest potential thus far include repetitive transcranial magnetic stimulation (rTMS), transcranial direct current stimulation (tDCS), and cranial electrotherapy stimulation (CES). The nature and some of the controversies distinguishing mTBI, PTSD, and mTBI/PTSD are reviewed along with evidence for shared underlying mechanisms. An overview of treatment applications for rTMS, tDCS, and CES are also reviewed. A novel variant of a minute pulsed electromagnetic stimulation technology linked to ongoing electroencephalograph monitoring known as the Flexyx Neurotherapy System is introduced with an overview of the technology and technique, as well as a summary of supportive data to date that explores potential applications for amelioration of these syndromes.

Modulating transcallosal and intra-hemispheric brain connectivity with tDCS: Implications for interventions in Aphasia

BACKGROUND/OBJECTIVE

Transcranial direct current stimulation (tDCS) can enhance or diminish cortical excitability levels depending on the polarity of the stimulation. One application of non-invasive brain-stimulation has been to modulate a possible inter-hemispheric disinhibition after a stroke. This disinhibition model has been developed mainly for the upper extremity motor system, but it is not known whether the language/speech-motor system shows a similar inter-hemispheric interaction. We aimed to examine physiological evidence of inter- and intra-hemispheric connectivity changes induced by tDCS of the right inferior frontal gyrus (IFG) using arterial-spin labeling (ASL) MRI.

METHODS

Using an MR-compatible DC-Stimulator, we applied anodal stimulation to the right IFG region of nine healthy adults while undergoing non-invasive cerebral blood flow imaging with arterial-spin labeling (ASL) before, during, and after the stimulation. All ASL images were then normalized and timecourses were extracted in regions of interest (ROIs), which were the left and right IFG regions, and the right supramarginal gyrus (SMG) in the inferior parietal lobule. Two additional ROIs (the right occipital lobe and the left fronto-orbital region) were taken as control regions.

RESULTS

Using regional correlation coefficients as a surrogate marker of connectivity, we could show that inter-hemispheric connectivity (right IFG with left IFG) decreased significantly (p < 0.05; r-scores from 0.67 to 0.53) between baseline and post-stimulation, while the intra-hemispheric connectivity (right IFG with right SMG) increased significantly (p < 0.05;r-scores from 0.74 to 0.81). A 2 × 2 ANOVA found a significant main effect of HEMISPHERE (F(8) = 6.83, p < 0.01) and a significant HEMISPHERE-by-TIME interaction (F(8) = 4.24, p < 0.05) in connectivity changes. The correlation scores did not change significantly in the control region pairs (right IFG with right occipital and right IFG with left fronto-orbital) over time.

CONCLUSION

Using an MR-compatible DC stimulator we showed that ASL-MRI can detect tDCS-induced modulation of brain connectivity within and between hemispheres. These findings might affect trial designs focusing on modulating the non-dominant hemisphere to enhance language/speech-motor functions.

Effect of Intermediate-Frequency Repetitive Transcranial Magnetic Stimulation on Recovery following Traumatic Brain Injury in Rats

Traumatic brain injury (TBI) represents a significant public health concern and has been associated with high rates of morbidity and mortality. Although several research groups have proposed the use of repetitive transcranial magnetic stimulation (rTMS) to enhance neuroprotection and recovery in patients with TBI, few studies have obtained sufficient evidence regarding its effects in this population. Therefore, we aimed to analyze the effect of intermediate-frequency rTMS (2 Hz) on behavioral and histological recovery following TBI in rats. Male Wistar rats were divided into six groups: three groups without TBI (no manipulation, movement restriction plus sham rTMS, and movement restriction plus rTMS) and three groups subjected to TBI (TBI only, TBI plus movement restriction and sham rTMS, and TBI plus movement restriction and rTMS). The movement restriction groups were included so that rTMS could be applied without anesthesia. Our results indicate that the restriction of movement and sham rTMS per se promotes recovery, as measured using a neurobehavioral scale, although rTMS was associated with faster and superior recovery. We also observed that TBI caused alterations in the CA1 and CA3 subregions of the hippocampus, which are partly restored by movement restriction and rTMS. Our findings indicated that movement restriction prevents damage caused by TBI and that intermediate-frequency rTMS promotes behavioral and histologic recovery after TBI.

Accuracy and reliability of the sensory test performed using the laryngopharyngeal endoscopic esthesiometer and rangefinder in patients with suspected obstructive sleep apnoea hypopnoea: protocol for a prospective double-blinded, randomised, exploratory study

INTRODUCTION

Patients with obstructive sleep apnoea hypopnoea syndrome (OSA) might have varying degrees of laryngopharyngeal mechanical hyposensitivity that might impair the brain's capacity to prevent airway collapse during sleep. However, this knowledge about sensory compromises in OSA comes from studies performed using methods with little evidence of their validity. Hence, the purpose of this study is to assess the reliability and accuracy of the measurement of laryngopharyngeal mechanosensitivity in patients with OSA using a recently developed laryngopharyngeal endoscopic esthesiometer and rangefinder (LPEER).

METHODS AND ANALYSIS

The study will be prospective and double blinded, with a randomised crossover assignment of raters performing the sensory tests. Subjects will be recruited from patients with suspected OSA referred for baseline polysomnography to a university hospital sleep laboratory. Intra-rater and inter-rater reliability will be evaluated using the Bland-Altman's limits of agreement plot, the intraclass correlation coefficient, and the Pearson or Spearman correlation coefficient, depending on the distribution of the variables. Diagnostic accuracy will be evaluated plotting ROC curves using standard baseline polysomnography as a reference. The sensory threshold values ​​for patients with mild, moderate and severe OSA will be determined and compared using ANOVA or the Kruskal-Wallis test, depending on the distribution of the variables. The LPEER could be a new tool for evaluating and monitoring laryngopharyngeal sensory impairment in patients with OSA. If it is shown to be valid, it could help to increase our understanding of the pathophysiological mechanisms of this condition and potentially help in finding new therapeutic interventions for OSA.

ETHICS AND DISSEMINATION

The protocol has been approved by the Institutional Review Board of Fundacion Neumologica Colombiana. The results will be disseminated through conference presentations and peer-reviewed publication.

TRIAL REGISTRATION

This trial was registered at Clinical Trials Accuracy of the sensory test using the lLaryngopharyngeal endoscopic esthesiometer in obstructive sleep apnea. Protocol ID: 201611-22405. ClinicalTrials.gov ID: NCT03109171.

Effects of low-frequency repetitive transcranial magnetic stimulation and neuromuscular electrical stimulation on upper extremity motor recovery in the early period after stroke: a preliminary study

OBJECTIVE

To assess the efficacy of inhibitory repetitive transcranial magnetic stimulation (rTMS) and neuromuscular electrical stimulation (NMES) on upper extremity motor function in patients with acute/subacute ischemic stroke.

METHODS

Twenty-five ischemic acute/subacute stroke subjects were enrolled in this randomized controlled trial. Experimental group 1 received low frequency (LF) rTMS to the primary motor cortex of the unaffected side + physical therapy (PT) including activities to improve strength, flexibility, transfers, posture, balance, coordination, and activities of daily living, mainly focusing on upper limb movements; experimental group 2 received the same protocol combined with NMES to hand extensor muscles; and the control group received only PT. Functional magnetic resonance imaging (fMRI) scan was used to evaluate the activation or inhibition of the affected and unaffected primary motor cortex.

RESULTS

No adverse effect was reported. Most of the clinical outcome scores improved significantly in all groups, however no statistically significant difference was found between groups due to the small sample sizes. The highest percent improvement scores were observed in TMS + NMES group (varying between 48 and 99.3%) and the lowest scores in control group (varying between 13.1 and 28.1%). Hand motor recovery was significant in both experimental groups while it did not change in control group. Some motor cortex excitability changes were also observed in fMRI.

CONCLUSION

LF-rTMS with or without NMES seems to facilitate the motor recovery in the paretic hand of patients with acute/subacute ischemic stroke. TMS or the combination of TMS + NMES may be a promising additional therapy in upper limb motor training. Further studies with larger numbers of patients are needed to establish their effectiveness in upper limb motor rehabilitation of stroke.

Disorders of Consciousness

Disorder of consciousness (DOC) is a state of prolonged altered consciousness, which can be categorized into coma, vegetative state, or minimally conscious state based on neurobehavioral function. The pathophysiology of DOC is poorly understood but recent advances in neuroimaging and advanced electrophysiological techniques may provide an improved understanding for the neural network involved with consciousness. The primary aim of DOC rehabilitation programs is to promote arousal while preventing secondary medical complications while providing education and training to families. Treatment interventions include both pharmacologic and nonpharmacologic programs, but there are currently no consensus treatment guidelines for individuals with DOC.

Usefulness of robotic gait training plus neuromodulation in chronic spinal cord injury: a case report

CONTEXT

Spinal cord injury (SCI) affects more than 2.5 million people worldwide, often leading to severe disability. Thus, a proper management of individuals with SCI is required either in the acute or in the post-acute rehabilitative phase.

FINDINGS

A 31-year-old man, affected by chronic SCI, underwent two different intensive rehabilitation treatments, including either LokomatPro or a paired LokomatPro-rTMS training. We evaluated the clinical, kinetic, and electrophysiological parameters before and after each training session. In particular, the intensive robotic training was articulated in a total of 40 one-hour training sessions (i.e. 5 times a week for 8 weeks), whereas the rTMS sessions were delivered 3 days per week for 3 consecutive weeks, just before the LokomatPro session. Only at the end of the experimental treatment, we observed an important improvement in nearly all parameters we investigated.

CLINICAL RELEVANCE

The combined LokomatPro-rTMS rehabilitation may be a valuable approach in improving the motor function in patients affected by SCI, even in the chronic phase.

Non-Invasive Brain Stimulation for Treatment of Focal Hand Dystonia: Update and Future Direction

Focal hand dystonia (FHD) is characterized by excessive and unwanted muscle activation in both the hand and arm resulting in impaired performance in particular tasks. Understanding the pathophysiology of FHD has progressed significantly for several decades and this has led to consideration of other potential therapies such as non-invasive brain stimulation (NIBS). A number of studies have been conducted to develop new therapy for FHD using transcranial magnetic stimulation and transcranial direct current stimulation. In this paper, we review previous studies and describe the potential therapeutic use of NIBS for FHD. We also discuss the future direction of NIBS to treat FHD.

Temporary deafferentation evoked by cutaneous anesthesia: behavioral and electrophysiological findings in healthy subjects

Motor function and motor excitability can be modulated by changes of somatosensory input. Here, we performed a randomized single-blind trial to investigate behavioral and neurophysiological changes during temporary deafferentation of left upper arm and forearm in 31 right-handed healthy adults. Lidocaine cream was used to anesthetize the skin from wrist to shoulder, sparing the hand. As control condition, on a different day, a neutral cream was applied to the same skin area. The sequence (first Lidocaine, then placebo or vice versa) was randomized. Behavioral measures included the Grating Orientation Task, the Von Frey hair testing and the Nine-hole-peg-test. Transcranial magnetic stimulation was used to investigate short-interval intracortical inhibition, stimulus response curves, motor evoked potential amplitudes during pre-innervation and the cortical silent period (CSP). Recordings were obtained from left first dorsal interosseous muscle and from left flexor carpi radialis muscle. During deafferentation, the threshold of touch measured at the forearm was significantly worse. Other behavioral treatment-related changes were not found. The CSP showed a significant interaction between treatment and time in first dorsal interosseous muscle. CSP duration was longer during Lidocaine application and shorter during placebo exposure. We conclude that, in healthy subjects, temporary cutaneous deafferentation of upper and lower arm may have minor effects on motor inhibition, but not on sensory or motor function for the adjacent non-anesthetized hand.

Hippocampal Neurophysiologic Changes after Mild Traumatic Brain Injury and Potential Neuromodulation Treatment Approaches

Traumatic brain injury (TBI) is the leading cause of death and disability in individuals below age 45, and five million Americans live with chronic disability as a result. Mild TBI (mTBI), defined as TBI in the absence of major imaging or histopathological defects, is responsible for a majority of cases. Despite the lack of overt morphological defects, victims of mTBI frequently suffer lasting cognitive deficits, memory difficulties, and behavioral disturbances. There is increasing evidence that cognitive and memory dysfunction is related to subtle physiological changes that occur in the hippocampus, and these impact both the phenotype of deficits observed and subsequent recovery. Therapeutic modulation of physiological activity by means of medications commonly used for other indications or brain stimulation may represent novel treatment approaches. This review summarizes the present body of knowledge regarding neurophysiologic changes that occur in the hippocampus after mTBI, as well as potential targets for therapeutic modulation of neurologic activity.

Electrical Stimulation Elicits Neural Stem Cells Activation: New Perspectives in CNS Repair

Researchers are enthusiastically concerned about neural stem cell (NSC) therapy in a wide array of diseases, including stroke, neurodegenerative disease, spinal cord injury, and depression. Although enormous evidences have demonstrated that neurobehavioral improvement may benefit from NSC-supporting regeneration in animal models, approaches to endogenous and transplanted NSCs are blocked by hurdles of migration, proliferation, maturation, and integration of NSCs. Electrical stimulation (ES) may be a selective non-drug approach for mobilizing NSCs in the central nervous system. This technique is suitable for clinical application, because it is well established and its potential complications are manageable. Here, we provide a comprehensive review of the emerging positive role of different electrical cues in regulating NSC biology in vitro and in vivo, as well as biomaterial-based and chemical stimulation of NSCs. In the future, ES combined with stem cell therapy or other cues probably becomes an approach for promoting brain repair.