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Journal of Motor Behavior 2017A review of the literature was performed to answer the following questions: Does motor cortex excitability correlate with motor function? Do motor cortex excitability... (Review)
Review
A review of the literature was performed to answer the following questions: Does motor cortex excitability correlate with motor function? Do motor cortex excitability and cortex activation change after a rehabilitation program that results in improvements in motor outcomes? Can the 10-20 electroencephalography (EEG) system be used to locate the primary motor cortex when employing transcranial direct current stimulation? Is there a bihemispheric imbalance in individuals with cerebral palsy similar to what is observed in stroke survivors? the authors found there is an adaptation in the geometry of motor areas and the cortical representation of movement is variable following a brain lesion. The 10-20 EEG system may not be the best option for locating the primary motor cortex and positioning electrodes for noninvasive brain stimulation in children with cerebral palsy.
Topics: Cerebral Palsy; Child; Electroencephalography; Humans; Motor Cortex; Neuronal Plasticity; Transcranial Direct Current Stimulation
PubMed: 27754798
DOI: 10.1080/00222895.2016.1219310 -
EFORT Open Reviews Dec 2023The aim of the study was to quantify motor cortex descending drive and voluntary activation (VA) in people with lower-limb OA compared to controls.
PURPOSE
The aim of the study was to quantify motor cortex descending drive and voluntary activation (VA) in people with lower-limb OA compared to controls.
METHODS
A systematic review and meta-analysis according to the PRISMA guidelines was carried out. Seven databases were searched until 30 December 2022. Studies assessing VA or responses to transcranial magnetic stimulation (TMS; i.e. motor evoked potential, intracortical facilitation, motor threshold, short-interval intracortical inhibition, and silent period) were included. Study quality was assessed using Joanna Briggs Institute criteria and evidence certainty using GRADE. The meta-analysis was performed using RevMan inverse variance, mixed-effect models.
RESULTS
Eighteen studies were included, all deemed low-quality. Quadriceps VA was impaired with knee OA compared to healthy controls (standardised mean difference (SMD) = 0.84, 95% CI = -1.12-0.56, low certainty). VA of the more symptomatic limb was impaired (SMD = 0.42, 95% CI = -0.75-0.09, moderate certainty) compared to the other limb in people with hip/knee OA. As only two studies assessed responses to TMS, very low-certainty evidence demonstrated no significant difference between knee OA and healthy controls for motor evoked potential, intracortical facilitation, resting motor threshold or short-interval intracortical inhibition.
CONCLUSIONS
Low-certainty evidence suggests people with knee OA have substantial impairments in VA of their quadriceps muscle when compared to healthy controls. With moderate certainty we conclude that people with hip and knee OA had larger impairments in VA of the quadriceps in their more painful limb compared to their non-affected/other limb.
PubMed: 38038371
DOI: 10.1530/EOR-23-0092 -
Sports Medicine (Auckland, N.Z.) Jul 2023Lateral ankle sprains are the most common ankle injuries in sports and have the highest recurrence rates. Almost half of the patients experiencing lateral ankle sprains...
BACKGROUND
Lateral ankle sprains are the most common ankle injuries in sports and have the highest recurrence rates. Almost half of the patients experiencing lateral ankle sprains develop chronic ankle instability. Patients with chronic ankle instability experience persistent ankle dysfunctions and detrimental long-term sequelae. Changes at the brain level are put forward to explain these undesirable consequences and high recurrence rates partially. However, an overview of possible brain adaptations related to lateral ankle sprains and chronic ankle instability is currently lacking.
OBJECTIVE
The primary purpose of this systematic review is to provide a comprehensive overview of the literature on structural and functional brain adaptations related to lateral ankle sprains and in patients with chronic ankle instability.
METHODS
PubMed, Web of Science, Scopus, Embase, EBSCO-SPORTDiscus and Cochrane Central Register of Controlled Trials were systematically searched until 14 December, 2022. Meta-analyses, systematic reviews and narrative reviews were excluded. Included studies investigated functional or structural brain adaptations in patients who experienced a lateral ankle sprain or with chronic ankle instability and who were at least 18 years of age. Lateral ankle sprains and chronic ankle instability were defined following the recommendation of the International Ankle Consortium. Three authors independently extracted the data. They extracted the authors' name, publication year, study design, inclusion criteria, participant characteristics, the sample size of the intervention and control groups, methods of neuroplasticity testing, as well as all means and standard deviations of primary and secondary neuroplasticity outcomes from each study. Data reported on copers were considered as part of the control group. The quality assessment tool for observational and cross-sectional studies was used for the risk of bias assessment. This study is registered on PROSPERO, number CRD42021281956.
RESULTS
Twenty articles were included, of which only one investigated individuals who experienced a lateral ankle sprain. In all studies combined, 356 patients with chronic ankle instability, 10 who experienced a lateral ankle sprain and 46 copers were included. White matter microstructure changes in the cerebellum have been related to lateral ankle sprains. Fifteen studies reported functional brain adaptations in patients with chronic ankle instability, and five articles found structural brain outcomes. Alterations in the sensorimotor network (precentral gyrus and supplementary motor area, postcentral gyrus and middle frontal gyrus) and dorsal anterior cingulate cortex were mainly found in patients with chronic ankle instability.
DISCUSSION
The included studies demonstrated structural and functional brain adaptations related to lateral ankle sprains and chronic ankle instability compared to healthy individuals or copers. These adaptations correlate with clinical outcomes (e.g. patients' self-reported function and different clinical assessments) and might contribute to the persisting dysfunctions, increased re-injury risk and long-term sequelae seen in these patients. Thus, rehabilitation programmes should integrate sensorimotor and motor control strategies to cope with neuroplasticity related to ligamentous ankle injuries.
Topics: Humans; Ankle; Cross-Sectional Studies; Ankle Joint; Joint Instability; Sprains and Strains; Ankle Injuries; Disease Progression; Brain
PubMed: 37155129
DOI: 10.1007/s40279-023-01834-z -
European Journal of Pain (London,... Sep 2016Acute muscle pain has both motor and sensory consequences, yet the effect of muscle pain on the primary sensory (S1) and motor (M1) cortices has yet to be systematically... (Meta-Analysis)
Meta-Analysis Review
Acute muscle pain has both motor and sensory consequences, yet the effect of muscle pain on the primary sensory (S1) and motor (M1) cortices has yet to be systematically evaluated. Here we aimed to determine the strength of the evidence for (1) altered activation of S1/M1 during and after pain, (2) the temporal profile of any change in activation and (3) the relationship between S1/M1 activity and the symptoms of pain. In September 2015, five electronic databases were systematically searched for neuroimaging and electrophysiological studies investigating the effect of acute experimental muscle pain on S1/M1 in healthy volunteers. Demographic data, methodological characteristics and primary outcomes for each study were extracted for critical appraisal. Meta-analyses were performed where appropriate. Twenty-five studies satisfied the inclusion criteria. There was consistent evidence from fMRI for increased S1 activation in the contralateral hemisphere during pain, but insufficient evidence to determine the effect at M1. Meta-analyses of TMS and EEG data revealed moderate to strong evidence of reduced S1 and corticomotor excitability during and following the resolution of muscle pain. A comprehensive understanding of the temporal profile of altered activity in S1/M1, and the relationship to symptoms of pain, is hampered by differences in methodological design, pain modality and pain severity between studies. Overall, the findings of this review indicate reduced S1 and corticomotor activity during and after resolution of acute muscle pain, mechanisms that could plausibly underpin altered sensorimotor function in pain. WHAT DOES THIS REVIEW ADD?: We provide the first systematic evaluation of the primary sensory (S1) and motor (M1) cortex response to acute experimental muscle pain in healthy volunteers. We present evidence from a range of methodologies to provide a comprehensive understanding of the effect of pain on S1/M1. Through meta-analyses we evaluate the strength of evidence concerning the direction and temporal profile of the S1/M1 response to acute muscle pain.
Topics: Acute Pain; Adolescent; Adult; Child; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Motor Cortex; Myalgia; Somatosensory Cortex; Young Adult
PubMed: 26913474
DOI: 10.1002/ejp.859 -
The Cochrane Database of Systematic... May 2016Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy of childhood. Untreated, this incurable disease, which has an X-linked recessive inheritance, is... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy of childhood. Untreated, this incurable disease, which has an X-linked recessive inheritance, is characterised by muscle wasting and loss of walking ability, leading to complete wheelchair dependence by 13 years of age. Prolongation of walking is a major aim of treatment. Evidence from randomised controlled trials (RCTs) indicates that corticosteroids significantly improve muscle strength and function in boys with DMD in the short term (six months), and strength at two years (two-year data on function are very limited). Corticosteroids, now part of care recommendations for DMD, are largely in routine use, although questions remain over their ability to prolong walking, when to start treatment, longer-term balance of benefits versus harms, and choice of corticosteroid or regimen.We have extended the scope of this updated review to include comparisons of different corticosteroids and dosing regimens.
OBJECTIVES
To assess the effects of corticosteroids on prolongation of walking ability, muscle strength, functional ability, and quality of life in DMD; to address the question of whether benefit is maintained over the longer term (more than two years); to assess adverse events; and to compare efficacy and adverse effects of different corticosteroid preparations and regimens.
SEARCH METHODS
On 16 February 2016 we searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, EMBASE, CINAHL Plus, and LILACS. We wrote to authors of published studies and other experts. We checked references in identified trials, handsearched journal abstracts, and searched trials registries.
SELECTION CRITERIA
We considered RCTs or quasi-RCTs of corticosteroids (e.g. prednisone, prednisolone, and deflazacort) given for a minimum of three months to patients with a definite DMD diagnosis. We considered comparisons of different corticosteroids, regimens, and corticosteroids versus placebo.
DATA COLLECTION AND ANALYSIS
The review authors followed standard Cochrane methodology.
MAIN RESULTS
We identified 12 studies (667 participants) and two new ongoing studies for inclusion. Six RCTs were newly included at this update and important non-randomised cohort studies have also been published. Some important studies remain unpublished and not all published studies provide complete outcome data.
PRIMARY OUTCOME MEASURE
one two-year deflazacort RCT (n = 28) used prolongation of ambulation as an outcome measure but data were not adequate for drawing conclusions.
SECONDARY OUTCOME MEASURES
meta-analyses showed that corticosteroids (0.75 mg/kg/day prednisone or prednisolone) improved muscle strength and function versus placebo over six months (moderate quality evidence from up to four RCTs). Evidence from single trials showed 0.75 mg/kg/day superior to 0.3 mg/kg/day on most strength and function measures, with little evidence of further benefit at 1.5 mg/kg/day. Improvements were seen in time taken to rise from the floor (Gowers' time), timed walk, four-stair climbing time, ability to lift weights, leg function grade, and forced vital capacity. One new RCT (n = 66), reported better strength, function and quality of life with daily 0.75 mg/kg/day prednisone at 12 months. One RCT (n = 28) showed that deflazacort stabilised muscle strength versus placebo at two years, but timed function test results were too imprecise for conclusions to be drawn.One double-blind RCT (n = 64), largely at low risk of bias, compared daily prednisone (0.75 mg/kg/day) with weekend-only prednisone (5 mg/kg/weekend day), finding no overall difference in muscle strength and function over 12 months (moderate to low quality evidence). Two small RCTs (n = 52) compared daily prednisone 0.75 mg/kg/day with daily deflazacort 0.9 mg/kg/day, but study methods limited our ability to compare muscle strength or function.
ADVERSE EFFECTS
excessive weight gain, behavioural abnormalities, cushingoid appearance, and excessive hair growth were all previously shown to be more common with corticosteroids than placebo; we assessed the quality of evidence (for behavioural changes and weight gain) as moderate. Hair growth and cushingoid features were more frequent at 0.75 mg/kg/day than 0.3 mg/kg/day prednisone. Comparing daily versus weekend-only prednisone, both groups gained weight with no clear difference in body mass index (BMI) or in behavioural changes (low quality evidence for both outcomes, one study); the weekend-only group had a greater linear increase in height. Very low quality evidence suggested less weight gain with deflazacort than with prednisone at 12 months, and no difference in behavioural abnormalities. Data are insufficient to assess the risk of fractures or cataracts for any comparison.Non-randomised studies support RCT evidence in showing improved functional benefit from corticosteroids. These studies suggest sustained benefit for up to 66 months. Adverse effects were common, although generally manageable. According to a large comparative longitudinal study of daily or intermittent (10 days on, 10 days off) corticosteroid for a mean period of four years, a daily regimen prolongs ambulation and improves functional scores over the age of seven, but with a greater frequency of side effects than an intermittent regimen.
AUTHORS' CONCLUSIONS
Moderate quality evidence from RCTs indicates that corticosteroid therapy in DMD improves muscle strength and function in the short term (twelve months), and strength up to two years. On the basis of the evidence available for strength and function outcomes, our confidence in the effect estimate for the efficacy of a 0.75 mg/kg/day dose of prednisone or above is fairly secure. There is no evidence other than from non-randomised trials to establish the effect of corticosteroids on prolongation of walking. In the short term, adverse effects were significantly more common with corticosteroids than placebo, but not clinically severe. A weekend-only prednisone regimen is as effective as daily prednisone in the short term (12 months), according to low to moderate quality evidence from a single trial, with no clear difference in BMI (low quality evidence). Very low quality evidence indicates that deflazacort causes less weight gain than prednisone after a year's treatment. We cannot evaluate long-term benefits and hazards of corticosteroid treatment or intermittent regimens from published RCTs. Non-randomised studies support the conclusions of functional benefits, but also identify clinically significant adverse effects of long-term treatment, and a possible divergence of efficacy in daily and weekend-only regimens in the longer term. These benefits and adverse effects have implications for future research and clinical practice.
Topics: Adrenal Cortex Hormones; Glucocorticoids; Humans; Male; Muscle Strength; Muscular Dystrophy, Duchenne; Prednisolone; Prednisone; Pregnenediones; Quality of Life; Randomized Controlled Trials as Topic; Walking
PubMed: 27149418
DOI: 10.1002/14651858.CD003725.pub4 -
Journal of Science and Medicine in Sport Apr 2020To synthesise the existing literature investigating if acute aerobic exercise enhances the response to experimentally-induced neuroplasticity paradigms.
OBJECTIVES
To synthesise the existing literature investigating if acute aerobic exercise enhances the response to experimentally-induced neuroplasticity paradigms.
METHODS
A systematic search of electronic databases Medline, PsycInfo and Embase was undertaken on 26 April 2018 and updated on 17 May 2019. Studies were included if they involved a bout of aerobic exercise; prescribed a bout of rest as a control condition; utilized a non-invasive brain stimulation paradigm to induce neuroplasticity; used TMS to assess neuroplasticity outcomes; participants were healthy 18-65year old males and females with no diagnosed neurological/psychological impairments.
RESULTS
Eight papers (containing 12 experiments) met inclusion criteria. All studies utilized cycling or treadmill exercise as their exercise modality, and exercise intensity ranged from low intensity continuous exercise to high-intensity interval exercise. Four neuroplasticity paradigms were employed including paired associative stimulation (PAS) (n=3), continuous theta-burst stimulation (cTBS) (n=2), intermittent theta-burst stimulation (iTBS) (n=2) and transcranial direct current stimulation (n=1). Aerobic exercise enhanced neuroplastic responses (compared to rest) in seven of the 12 experiments.
CONCLUSIONS
This review provides emerging evidence that acute aerobic exercise can enhance the response to experimentally-induced neuroplasticity paradigms. However, there remains great variability in the study design and reporting of effects in these studies and thus a more standardized approach is encouraged to better understand the relationship between acute aerobic exercise and neuroplasticity. Future studies should consider optimizing intensity, paradigms and duration of both exercise and neuroplasticity paradigms employed.
Topics: Exercise; Humans; Motor Cortex; Neuronal Plasticity
PubMed: 31759829
DOI: 10.1016/j.jsams.2019.10.015 -
Clinical Neurophysiology : Official... May 2022Mood disorders have been associated with lateralized brain dysfunction, on the left-side for depression and right-side for mania. Consistently, asymmetry of cortical... (Meta-Analysis)
Meta-Analysis
OBJECTIVE
Mood disorders have been associated with lateralized brain dysfunction, on the left-side for depression and right-side for mania. Consistently, asymmetry of cortical excitability, as measured by transcranial magnetic stimulation (TMS) has been reported. Here, we reviewed and summarized work assessing such measures bilaterally in mood disorders.
METHODS
We performed a systematic review and extracted data to perform meta-analyses of interhemispheric asymmetry of motor cortex excitability, assessed with TMS, across different mood disorders and in healthy subjects. Additionally, potential predictors of interhemispheric asymmetry were explored.
RESULTS
Asymmetry of resting motor threshold (MT) among healthy volunteers was significant, favoring lower right relative to left-hemisphere excitability. MT was also significantly asymmetric in major depressive disorder (MDD), but with lower excitability of the left -hemisphere, when compared to the right, no longer observed in recovered patients. Findings on intracortical facilitation were similar. The few trials including bipolar depression revealed similar trends for imbalance, but with lower right hemisphere excitability, relative to the left.
CONCLUSIONS
There is interhemispheric asymmetry of motor cortical excitability in MDD, with lower excitability on left when compared to right-side. Interhemispheric asymmetry, with lower right relative to left-sided excitability, was found for bipolar depression and was also suggested for healthy volunteers, in a pattern that is clearly distinct from MDD.
SIGNIFICANCE
Mood disorders display asymmetric motor cortical excitability that is distinct from that found in healthy volunteers, supporting the presence of lateralized brain dysfunction in these disorders.
Topics: Cortical Excitability; Depressive Disorder, Major; Evoked Potentials, Motor; Functional Laterality; Humans; Mood Disorders; Motor Cortex; Transcranial Magnetic Stimulation
PubMed: 35240425
DOI: 10.1016/j.clinph.2022.01.137 -
Neurosurgery Feb 2019Motor cortex stimulation (MCS) is routinely used for the treatment of chronic neuropathic pain but its effect on quality of life remains uncertain.
BACKGROUND
Motor cortex stimulation (MCS) is routinely used for the treatment of chronic neuropathic pain but its effect on quality of life remains uncertain.
OBEJCTIVE
To systematically review the published literature on MCS and quality of life and report the effects of this therapy in a series of patients prospectively followed in our center.
METHODS
The systematic literature review was conducted using the search words "motor cortex stimulation and pain and neurosurgery" and "motor cortex stimulation and pain and quality of life." Quality of life in our clinical trial was investigated in a series of 10 patients with chronic neuropathic pain prospectively followed for 12 mo after MCS.
RESULTS
Two hundred eighteen nonreplicated articles were pooled for analysis. Of these, 6 described measures of quality of life in the pre- and postoperative period. In these studies, 64 patients with different clinical conditions associated with neuropathic pain were followed for 6 to 84 mo after MCS surgery. Improvement in quality of life ranged from 35% to 85%. In our clinical series, visual analog scale (VAS), SF-12 physical (PhysCS), and mental scores (MenCS) recorded 12 mo after MCS were improved by 60 ± 10% (P = .002), 50 ± 13% (P = .002), and 22 ± 6% (P = .01), respectively. No significant correlation was found between postoperative improvement in pain and either PhysCS (r = 0.18; P = .6) or MenCS (r = -0.24; P = .5).
CONCLUSION
MCS improves quality of life in patients with chronic refractory neuropathic pain. Additional factors other than a simple analgesic effect may contribute to these results.
Topics: Adult; Electric Stimulation Therapy; Female; Humans; Male; Middle Aged; Motor Cortex; Neuralgia; Pain Management; Quality of Life; Treatment Outcome
PubMed: 29547990
DOI: 10.1093/neuros/nyy060 -
European Neurology 2021Facial pain (FP) is a type of neuropathic pain which recognizes both central and peripheral causes. It can be difficult to treat because it can often become resistant to...
INTRODUCTION
Facial pain (FP) is a type of neuropathic pain which recognizes both central and peripheral causes. It can be difficult to treat because it can often become resistant to pharmacological treatments. Motor Cortex Stimulation (MCS) has been used in selected cases, but the correct indications of MCS in FP have not been fully established. Here we systematically reviewed the literature regarding MCS in FP analysing the results of this technique and studying the possible role of different factors in the prognosis of these patients.
METHODS
A literature search was performed through different databases (PubMed, Scopus, and Embase) according to PRISMA guidelines using the following terms in any possible combination: "facial pain" or "trigeminal" or "anaesthesia dolorosa" and "motor cortex stimulation."
RESULTS
111 articles were reviewed, and 12 studies were included in the present analysis for a total of 108 patients. Overall, at latest follow-up (FU), 70.83% of patients responded to MCS. The preoperative VAS significantly decreased at the latest FU (8.83 ± 1.17 and 4.31 ± 2.05, respectively; p < 0.0001). Younger age (p = 0.0478) and a peripheral FP syndrome (p = 0.0006) positively affected the definitive implantation rate on univariate analysis. Younger age emerged as a factor strongly associated to a higher probability to go to a definitive MCS implant on multivariate analysis (p = 0.0415).
CONCLUSION
Our results evidenced the effectiveness of MCS in treating FP. Moreover, the younger age emerged as a positive prognostic factor for definitive implantation. Further studies with longer FU are needed to better evaluate the long-term results of MCS.
Topics: Facial Pain; Humans; Motor Cortex; Neuralgia; Prognosis; Treatment Outcome
PubMed: 33853065
DOI: 10.1159/000514827 -
Frontiers in Human Neuroscience 2023Repetitive transcranial magnetic stimulation (rTMS) is used to induce long-lasting changes (aftereffects) in cortical excitability, which are often measured via...
INTRODUCTION
Repetitive transcranial magnetic stimulation (rTMS) is used to induce long-lasting changes (aftereffects) in cortical excitability, which are often measured via single-pulse TMS (spTMS) over the motor cortex eliciting motor-evoked potentials (MEPs). rTMS includes various protocols, such as theta-burst stimulation (TBS), paired associative stimulation (PAS), and continuous rTMS with a fixed frequency. Nevertheless, subsequent aftereffects of rTMS are variable and seem to fail repeatability. We aimed to summarize standard rTMS procedures regarding their test-retest reliability. Hereby, we considered influencing factors such as the methodological quality of experiments and publication bias.
METHODS
We conducted a literature search via PubMed in March 2023. The inclusion criteria were the application of rTMS, TBS, or PAS at least twice over the motor cortex of healthy subjects with measurements of MEPs via spTMS as a dependent variable. The exclusion criteria were measurements derived from the non-stimulated hemisphere, of non-hand muscles, and by electroencephalography only. We extracted test-retest reliability measures and aftereffects from the eligible studies. With the Rosenthal fail-safe N, funnel plot, and asymmetry test, we examined the publication bias and accounted for influential factors such as the methodological quality of experiments measured with a standardized checklist.
RESULTS
A total of 15 studies that investigated test-retest reliability of rTMS protocols in a total of 291 subjects were identified. Reliability measures, i.e., Pearson's and intraclass correlation coefficient (ICC) applicable from nine studies, were mainly in the small to moderate range with two experiments indicating good reliability of 20 Hz rTMS ( = 0.543) and iTBS ( = 0.55). The aftereffects of rTMS procedures seem to follow the heuristics of respective inhibition or facilitation, depending on the protocols' frequency, and application pattern. There was no indication of publication bias and the influence of methodological quality or other factors on the reliability of rTMS.
CONCLUSION
The reliability of rTMS appears to be in the small to moderate range overall. Due to a limited number of studies reporting test-retest reliability values and heterogeneity of dependent measures, we could not provide generalizable results. We could not identify any protocol as superior to the others.
PubMed: 37771347
DOI: 10.3389/fnhum.2023.1237713