Effects of square-stepping exercise on executive function in individuals with Parkinson's disease: A randomized controlled pilot study.

With the aging population, the incidence of Parkinson's disease (PD) increases over time. In this study, a popular and interesting exercise called the square-stepping exercise (SSE) was chosen as an intervention for people with PD. The purpose of the study was to investigate the effects of SSE on cognitive function, especially executive function. Twenty-eight participants were recruited and randomly assigned to the experimental group (n=14) or the control group (n=14). The duration of the intervention for both groups was 8 weeks, twice a week. The outcomes, including the trail making test, the digit span task, the Montreal cognitive assessment, and the Parkinson's disease questionnaire, were evaluated before the intervention, after the intervention, and at 1-month follow-up. The results showed that executive function improved significantly on the digit span task after SSE training. Consequently, SSE could be an effective intervention to improve executive function in people with PD.

Balance Training Modulates Cortical Inhibition in Individuals with Parkinson's Disease: A Randomized Controlled Trial.

BACKGROUND: Most individuals with Parkinson's disease (PD) develop balance dysfunction. Previous studies showed that individuals with PD have abnormal corticomotor changes related to severity of motor symptoms and disease progression. Cortical disinhibition was observed in PD and this alteration can be an early sign of PD. Balance training seems to be an effective intervention to improve balance in individuals with PD. However, it is not much known about the effect of balance training on cortical neuroplasticity in PD population. OBJECTIVE: To investigate the effects of balance training on corticomotor excitability in individuals with PD. METHODS: Twenty-eight PD participants were recruited and randomly assigned to either the balance training (BT) or the control (CON) group. Both groups underwent 16 training sessions over 8 weeks. Outcome measures for corticomotor inhibition included the cortical silent period (CSP) and short-interval intracortical inhibition (SICI) on transcranial magnetic stimulation. Balance performance was measured using the Mini-Balance Evaluation Systems Test (Mini-BEST) and the Timed Up and Go (TUG) test. RESULTS: Participants in the BT group showed a significant increase in corticomotor inhibition (CSP: P = .028, SICI: P = .04) and a significant improvement in balance performance (Mini-BEST: P = .001, TUG: P = .04) after training. Compared to the CON group, the BT group showed a greater increase in corticomotor inhibition (CSP: P = .017, SICI: P = .046) and better improvement in balance (Mini-BEST: P = .046). CONCLUSION: Balance training could modulate corticomotor inhibition in the primary motor cortex and improve balance performance in individuals with PD.

Altered corticospinal excitability of scapular muscles in individuals with shoulder impingement syndrome.

The purpose of this study is to assess and compare corticospinal excitability in the upper and lower trapezius and serratus anterior muscles in participants with and without shoulder impingement syndrome (SIS). Fourteen participants with SIS, and 14 without SIS were recruited through convenient sampling in this study. Transcranial magnetic stimulation assessment of the scapular muscles was performed while the participants were holding their arm at 90 degrees scaption. The motor-evoked potential (MEP), active motor threshold (AMT), latency of MEP, cortical silent period (CSP), activated area and center of gravity (COG) of cortical mapping were compared between groups using the Mann-Whitney U tests. The SIS group demonstrated following significances, higher AMTs of the lower trapezius (SIS: 0.60 ± 0.06; Comparison: 0.54 ± 0.07, p = 0.028) and the serratus anterior (SIS: 0.59 ± 0.04; Comparison: 0.54 ± 0.06, p = 0.022), longer CSP of the lower trapezius (SIS: 62.23 ± 22.87 ms; Comparison: 45.22 ± 14.64 ms, p = 0.019), and posteriorly shifted COG in the upper trapezius (SIS: 1.88 ± 1.06; Comparison: 2.76 ± 1.55, p = 0.048) and the serratus anterior (SIS: 2.13 ± 1.02; Comparison: 3.12 ± 1.88, p = 0.043), than the control group. In conclusion, participants with SIS demonstrated different organization of the corticospinal system, including decreased excitability, increased inhibition, and shift in motor representation of the scapular muscles.

Correlation between intraoperative mapping and monitoring and functional outcomes following supratentorial glioma surgery.

OBJECTIVES: Intraoperative neurophysiological monitoring (IONM) has long been regarded as the "gold standard" when resecting a supratentorial glioma, as it facilitates the goals of maximal tumor resection and preservation of sensorimotor function. The purpose of the present study was to evaluate the ability of motor evoked potentials (MEPs) monitoring or subcortical mapping (SCM), alone or in combination, to predict postoperative functional outcomes in glioma surgery. MATERIALS AND METHODS: We retrospectively reviewed patients with supratentorial glioma that underwent craniotomy for tumor removal with IONM. Statistical analyses were used to evaluate whether the following criteria correlated with postoperative functional outcomes: Reduced amplitude (>50% reduction) or disappearance of MEPs (criterion 1), SCM with a stimulation intensity threshold less than 3 mA (criterion 2), the presence of both two phenomena (criterion 3), or either one of the two phenomena (criterion 4). RESULTS: Ninety-two patients were included in this study, of whom 15 sustained new postoperative deficits, 4 experienced improved functional status, and 73 were unchanged. Postoperative functional status correlated significantly with all four criteria, and especially with criterion 3 (r = 0.647, P = 0.000). Sensitivity of IONM was better if using criteria 2 and 4, but specificity was better if using criteria 1 and 3. Criterion 3 had the most favorable overall results. CONCLUSION: Using statistical methodology, our study indicates that concomitant interpretation of MEPs and SCM is the most accurate predictor of functional outcomes following supratentorial glioma surgery. However, accurate interpretations of the monitoring results by experienced neurophysiologists are essential.

Mitochondrial DNA m.3243A>G mutation rarely causes CADASIL-like phenotype.

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are 2 monogenic cerebral small vessel diseases sharing several common clinical features including young stroke, migraine, and cognitive dysfunction. The aim of this study was to understand the role of MELAS in patients with CADASIL-like manifestations. We screened 429 unrelated patients with genetically unassigned CADASIL-like syndrome for mitochondrial DNA m.3243A>G mutation. None of them were found to have the mutation. Our finding suggests that m.3243A>G rarely causes CADASIL-like phenotype. It may be not necessary to consider MELAS as a differential diagnosis of CADASIL. Screening m.3243A>G in patients with CADASIL-like phenotype is of limited value.

Electrophysiological basis for antiepileptic drugs in migraine prevention.

Migraine and epilepsy share in many ways with regard to their clinical presentation and pathophysiological mechanisms. A state of central hyper-excitability or hyper-responsivity is fundamental in their pathophysiology. Antiepileptic drugs (AEDs) have long been used for migraine prevention, other than for seizure control. Evidence from numerous clinical trials has well demonstrated the therapeutic effects of some of the AEDs in this regard. In this paper, we will first discuss the clinical similarity between migraine and epilepsy. Then, to address the rationale of AEDs usage in migraine prevention, we focus on those electrophysiological studies conducted in patients with migraine demonstrating evidence of central hyper-excitability or hyper-responsivity. Although controversies remain, three common findings are derived from the literature: (1) cortical hyper-excitability, (2) impaired intra-cortical inhibition or increased intra-cortical facilitation, and (3) dis-habituation (hyper-responsivity). Each single feature may actually represent one of the different manifestations derived from an overall central excitation/inhibition imbalance. Finally, we review those studies addressing the therapeutic effects of AEDs and the associated alteration in central excitability. These studies provided direct evidence that effective prevention by AEDs is associated with the restoration of excitation/inhibition imbalance.

Noisy Galvanic Vestibular Stimulation (Stochastic Resonance) Changes Electroencephalography Activities and Postural Control in Patients with Bilateral Vestibular Hypofunction.

Patients with bilateral vestibular hypofunction (BVH) often suffer from imbalance, gait problems, and oscillopsia. Noisy galvanic vestibular stimulation (GVS), a technique that non-invasively stimulates the vestibular afferents, has been shown to enhance postural and walking stability. However, no study has investigated how it affects stability and neural activities while standing and walking with a 2 Hz head yaw turning. Herein, we investigated this issue by comparing differences in neural activities during standing and walking with a 2 Hz head turning, before and after noisy GVS. We applied zero-mean gaussian white noise signal stimulations in the mastoid processes of 10 healthy individuals and seven patients with BVH, and simultaneously recorded electroencephalography (EEG) signals with 32 channels. We analyzed the root mean square (RMS) of the center of pressure (COP) sway during 30 s of standing, utilizing AMTI force plates (Advanced Mechanical Technology Inc., Watertown, MA, USA). Head rotation quality when walking with a 2 Hz head yaw, with and without GVS, was analyzed using a VICON system (Vicon Motion Systems Ltd., Oxford, UK) to evaluate GVS effects on static and dynamic postural control. The RMS of COP sway was significantly reduced during GVS while standing, for both patients and healthy subjects. During walking, 2 Hz head yaw movements was significantly improved by noisy GVS in both groups. Accordingly, the EEG power of theta, alpha, beta, and gamma bands significantly increased in the left parietal lobe after noisy GVS during walking and standing in both groups. GVS post-stimulation effect changed EEG activities in the left and right precentral gyrus, and the right parietal lobe. After stimulation, EEG activity changes were greater in healthy subjects than in patients. Our findings reveal noisy GVS as a non-invasive therapeutic alternative to improve postural stability in patients with BVH. This novel approach provides insight to clinicians and researchers on brain activities during noisy GVS in standing and walking conditions in both healthy and BVH patients.

Comparison of Corticosteroid Injection Dosages in Mild to Moderate Idiopathic Carpal Tunnel Syndrome: A Randomized Controlled Trial.

OBJECTIVES: To evaluate whether the therapeutic effect of ultrasound-guided injections with 10 mg or 40 mg triamcinolone acetonide (TA) was dose-dependent in patients with idiopathic mild to moderate carpal tunnel syndrome (CTS). DESIGN: Prospective, double-blind, randomized controlled study with 12 weeks of follow-up. SETTING: Rehabilitation outpatient clinic of a single medical center. PARTICIPANTS: Patients with CTS (N=56). INTERVENTION: Participants were randomly assigned to 2 treatment groups for injection: (A) 40 mg TA+2% lidocaine hydrochloride or (B) 10 mg TA+2% lidocaine hydrochloride. MAIN OUTCOME MEASURES: Participants were evaluated using visual analog scale (VAS) and Boston Carpal Tunnel Questionnaire (BCTQ, including Symptom Severity Scale [SSS] and Functional Status Scale [FSS]) at baseline and 6 and 12 weeks after injection). Nerve conduction studies, including parameters of distal motor latency, amplitude of compound motor action potential, amplitude of sensory nerve action potential and sensory nerve conduction velocity of median nerve, and the patient's subjective impression of improvement, were recorded before injection and 6 and 12 weeks after injection. RESULTS: No significant differences were observed in baseline demographic characteristics and clinical evaluations. The parameters in group A and B at baseline, 6 weeks, and 12 weeks were (1) SSS: 2.17±0.14, 1.19±0.04, and 1.34±0.09 and 1.87±0.11, 1.21±0.07, and 1.26±0.04; (2) FSS: 1.63±0.07, 1.27±0.06, and 1.33±0.08 and 1.50±0.10, 1.18±0.05, and 1.26±0.05; (3) VAS: 6.4±0.3, 2.2±0.3, and 3.0±0.1 and 6.7±0.3, 2.0±0.3, and 3.1±0.3, respectively, and significantly decreased after 6 and 12 weeks in both treatment groups (P<.05). All parameters of nerve conduction studies improved in both groups after 12 weeks (P<.05). VAS, BCTQ, and nerve conduction studies did not show significant intergroup differences after 6 and 12 weeks. CONCLUSION: In patients with idiopathic mild to moderate CTS, ultrasound-guided injection with 10 and 40 mg TA yield similar improvements in BCTQ, VAS, and nerve conduction studies at the 12-week follow-up.

Paired nociceptive blink stimuli can facilitate trigeminofacial circuit at a long inter-stimulus interval.

BACKGROUNDS: Conditioned responses of paired nociceptive blink reflex (nBR) can reflect the excitability of trigeminofacial circuit. In the present study, we studied paired homotopic nBR with different inter-stimulus intervals (ISI). By monitoring different ISIs and consequential conditioned R2 of nBR, we aimed to investigate the impact of ISIs on the recovery cycle of nBR in normal individuals. METHODS: Twelve healthy volunteers (mean age: 29.9 ± 7.0 years; M/F: 7/5) were enrolled in this study. After individuals' reflex threshold was determined, triple pulses were given in pairs with ISIs 125 to 10000 milliseconds randomly. We calculated the ratio of conditioned and unconditioned nBR area-under-curve (AUC) (defined as recovery index), and amplitude of each ISI. RESULTS: The average latency of unconditioned nR2 is 42.6 ± 5.5 ms, with amplitude of 53.4 ± 43.9 µV and the AUC of 563.5 ± 480.6 ms·µV. The conditioned nBR/unconditioned nBR response ratio was less than 100% while the ISI is shorter than 1667 ms, suggesting an inhibited conditioned response. The recovery index and the amplitude of conditioned nBR gradually increased with increasing ISI. The recovery index was greater than 100% at ISI of 10 s (p = 0.005), implying full recovery and facilitation of conditioned nBR. CONCLUSION: Our study established the time-dependent dynamic recovery curve of paired nBR. The facilitated nBR at ISI longer than 10 s might be associated with temporal summation to the facial motor neurons after repeated stimuli. Our study results provided potential applications for patients with pain disorders involving trigeminofacial region.

Aberrant Sensory Gating of the Primary Somatosensory Cortex Contributes to the Motor Circuit Dysfunction in Paroxysmal Kinesigenic Dyskinesia.

Paroxysmal kinesigenic dyskinesia (PKD) is conventionally regarded as a movement disorder (MD) and characterized by episodic hyperkinesia by sudden movements. However, patients of PKD often have sensory aura and respond excellently to antiepileptic agents. PRRT2 mutations, the most common genetic etiology of PKD, could cause epilepsy syndromes as well. Standing in the twilight zone between MDs and epilepsy, the pathogenesis of PKD is unclear. Gamma oscillations arise from the inhibitory interneurons which are crucial in the thalamocortical circuits. The role of synchronized gamma oscillations in sensory gating is an important mechanism of automatic cortical inhibition. The patterns of gamma oscillations have been used to characterize neurophysiological features of many neurological diseases, including epilepsy and MDs. This study was aimed to investigate the features of gamma synchronizations in PKD. In the paired-pulse electrical-stimulation task, we recorded the magnetoencephalographic data with distributed source modeling and time-frequency analysis in 19 patients of newly-diagnosed PKD without receiving pharmacotherapy and 18 healthy controls. In combination with the magnetic resonance imaging, the source of gamma oscillations was localized in the primary somatosensory cortex. Somatosensory evoked fields of PKD patients had a reduced peak frequency (p < 0.001 for the first and the second response) and a prolonged peak latency (the first response p = 0.02, the second response p = 0.002), indicating the synchronization of gamma oscillation is significantly attenuated. The power ratio between two responses was much higher in the PKD group (p = 0.013), indicating the incompetence of activity suppression. Aberrant gamma synchronizations revealed the defective sensory gating of the somatosensory area contributes the pathogenesis of PKD. Our findings documented disinhibited cortical function is a pathomechanism common to PKD and epilepsy, thus rationalized the clinical overlaps of these two diseases and the therapeutic effect of antiepileptic agents for PKD. There is a greater reduction of the peak gamma frequency in PRRT2-related PKD than the non-PRRT PKD group (p = 0.028 for the first response, p = 0.004 for the second response). Loss-of-function PRRT2 mutations could lead to synaptic dysfunction. The disinhibiton change on neurophysiology reflected the impacts of PRRT2 mutations on human neurophysiology.

Using subdural strip electrodes to define functional sensory nerves and the most inferior functional portion of the conus medullaris during detethering surgeries for tethered cord syndrome: a pilot study.

OBJECTIVE: The aim of this study was to investigate the feasibility of using subdural strip electrodes, placed just rostral to the surgical field, to record sensory evoked potentials (SEPs) from the lumbosacral sensory nerves and define the most inferior functional portion of the conus medullaris during detethering surgery for spinal dysraphism and/or tethered cord syndrome (TCS). METHODS: Six patients, 2 boys and 4 girls, aged 0.5 to 16 years, were enrolled in this study. One patient had lipomyelomeningocele-related, 4 had myelomeningocele-related, and 1 had diastematomyelia and lipomyelomeningocele-related TCS. In addition to the routine preparations that are needed for performing functional mapping and monitoring during surgery for spinal dysraphism and TCS, the patients had a 1 × 4 strip of electrodes placed rostral to the surgical field, where it was secured by a surgeon after opening the dura. With the patient under total intravenous anesthesia, the sensory nerves and conus medullaris were stimulated with a concentric bipolar electrode over the surgical field while SEPs were recorded with the strip electrodes to identify any possible sensory roots with remaining function and the most inferior functional portion of the conus medullaris. RESULTS: The SEP amplitudes that were recorded with the subdural strip electrodes ranged from 4 to 400 µV, and the responses to sensory nerve stimulation were frequently much larger than were those to conus stimulation. Use of the SEP recordings for sensory mapping along with the routine mapping and monitoring techniques allowed detethering to be completed such that none of the patients sustained any new functional deficit after surgery. CONCLUSIONS: Recording SEPs from the functional sensory nerves and conus medullaris through subdural strip electrodes proved to be a feasible and valuable tool during detethering surgery in young patients. This approach may help surgeons achieve maximal detethering while preserving important sensory functions, consequently retaining the patient's quality of life.

Sonographic median nerve change after steroid injection for carpal tunnel syndrome.

INTRODUCTION: The sonographic changes of the median nerve after steroid injection for carpal tunnel syndrome (CTS) still require investigation. METHODS: Sixty-two patients with CTS were included. The Boston Carpal Tunnel Questionnaire was administered, and ultrasonographic examinations were performed before and at 2, 6, and 12 weeks after steroid injection. At 12 weeks, general improvement was scored on a 6-point Likert scale. RESULTS: After treatment, the cross-sectional area (CSA) of the median nerve was significantly reduced at 2-, 6-, and 12-week follow-ups (for each, P < 0.001, analysis of variance). The "significant improvement" group (n = 39) had a significantly greater reduction in the CSA at the carpal tunnel inlet (P = 0.014) and CSA in the proximal carpal tunnel (P = 0.003) compared with the "little/no improvement" group (n = 23). DISCUSSION: Sonographic measurement of CSA may be considered complementary to the standard clinical evaluation in monitoring of treatment response in patients with CTS. Muscle Nerve 58: 402-406, 2018.

The effect of additional joint mobilization on neuromuscular performance in individuals with functional ankle instability.

OBJECTIVES: To examine the effects of joint mobilization and exercise training on neuromuscular performance in individuals with functional ankle instability (FAI). DESIGN: A cross-sectional study. PARTICIPANTS: Forty five subjects with FAI were randomized into three groups: control (CG, n = 15, 27.9 ±â€¯6.6yr), training (TG, n = 15, 26.9 ±â€¯5.8yr) and mobilization with training group (MTG, n = 15, 26.5 ±â€¯4.8yr). INTERVENTION: Four weeks of neuromuscular training for TG; neuromuscular training and joint mobilization for MTG. MAIN OUTCOME MEASURES: Electromyography of the peroneus longus (PL), tibialis anterior (TA), and soleus (SOL) and the reaching distance of the Y balance test (YBT), dorsiflexion range of motion (DFROM), Cumberland ankle instability tool (CAIT), and global rating scale (GRS). Two-way repeated measures MANOVA were used with the significance level p < .05. RESULTS: MANOVA found significant group by time interactions on posterolateral reaching distance (p = .032), PL activation (p = .006-.03), DFROM (p < .001), CAIT (p < .001) and GRS (p < .001). The post hoc tests indicated significantly improved PL muscle activity and posterolateral reaching distance for MTG compared to TG (p = .004) and CG (p = .006). CONCLUSION: Joint mobilization resulted in additional benefits on self-reported ankle instability severity, dorsiflexion mobility, and posterolateral balance performance in individuals with FAI, but its effects on general improvement, muscle activation, and other balance tasks remained uncertain.

Localization of the trunk muscles using musculoskeletal ultrasound guidance for pedicle screw stimulation during spine surgery.

The precise placement of recording electrodes at the relevant myotome is mandatory while performing pedicle screw stimulation (PSS) during spine surgery; however, their placement at trunk muscles is challenging. This study aimed to determine whether ultrasound guidance is useful for trunk muscle localization for PSS during spine surgery. A retrospective clinical study was conducted from a prospective database. Eighty-four patients eligible for spine surgery were recruited. Ultrasound was used to localize the intercostal, rectus abdominis, and internal oblique and psoas muscles if pedicle screw placement was performed at T3 to L1. After the operation, patients were examined for any new neurological deficits related to this procedure, and computed tomography was performed to check screw position if indicated. Four to 22 pedicle screws were used for spinal fixation. The threshold of stimulus to obtain a compound muscle action potential ranged from 1.29 to >20mA during PSS. Six of our patients sustained new postoperative deficits, and only one case was related directly to pedicel screw misplacement. Loss of motor evoked potential (MEP) over both the lower limbs was noted during pedicle screw placement, and the stimulus threshold during PSS were 1.29mA at the left T9 and 3.8mA at the right T5 level. MEP remained absent at the end of surgery despite removal of those two screws. The patient woke with significant weakness in both lower limbs (muscle power 0/0) and voiding difficulty. Fortunately, he regained walking ability 4.5months later after intensive rehabilitation therapy.

Efficacy of Combined Ultrasound-Guided Steroid Injection and Splinting in Patients With Carpal Tunnel Syndrome: A Randomized Controlled Trial.

OBJECTIVE: To compare the effectiveness of local steroid injection plus splinting with that of local steroid injection alone using clinical and electrophysiological parameters in patients with carpal tunnel syndrome (CTS). DESIGN: Randomized controlled study with 12 weeks of follow-up. SETTING: Tertiary care center. PARTICIPANTS: Volunteer sample of patients (N=52) diagnosed with CTS. INTERVENTIONS: Participants were randomly assigned to the steroid injection group (n=26) or the steroid injection-plus-splinting group (n=26). Patients of both groups received ultrasound-guided steroid injection with 1mL of 10mg (10mg/mL) triamcinolone acetonide (Shincort) and 1mL of 2% lidocaine hydrochloride (Xylocaine). Participants in the second group also wore a volar splint in the neutral position while sleeping and also during daytime whenever possible for the 12-week intervention period. MAIN OUTCOME MEASURES: Participants were evaluated before the treatment and at 6 and 12 weeks after the onset of treatment. The primary outcome measure was Boston Carpal Tunnel Questionnaire scores. The secondary outcome measures were as follows: scores on the visual analog scale for pain; electrophysiological parameters, including median nerve distal motor latency, sensory nerve conduction velocity (SNCV), and compound muscle action potential and sensory nerve action potential (SNAP) amplitudes; and patient's subjective impression of improvement. RESULTS: At 12-week follow-up, improvements in symptom severity and functional status scores on the Boston Carpal Tunnel Questionnaire as well as SNCV and SNAP amplitudes were greater in the group that received steroid injection combined with splinting than in the group that received steroid injection alone. The between-group difference was .48 points (95% confidence interval [CI], .09-.88 points; P=.032) in the Symptom Severity Scale score, .37 points (95% CI, .06-.67 points; P=.019) in the Functional Status Scale score, 3.38m/s (95% CI, 0.54-6.22m/s; P=.015) in the SNCV amplitude, and 3.21µV (95% CI, 0.00-6.46µV; P=.025) in the SNAP amplitude. CONCLUSIONS: In people with CTS, steroid injection combined with splinting resulted in modestly greater reduction of symptoms, superior functional recovery, and greater improvement in nerve function at 12-week follow-up as compared with steroid injection alone. However, these small differences are of unclear clinical significance.

Efficacy of continuous theta burst stimulation of the primary motor cortex in reducing migraine frequency: A preliminary open-label study.

BACKGROUND: Theta burst stimulation is a type of pattern-specific repetitive transcranial magnetic stimulation that requires less stimulation time and lower intensity to induce long-lasting effects comparable to those of other repetitive transcranial magnetic stimulation protocols. This pilot study investigated whether continuous theta burst stimulation (cTBS) on the primary motor cortex reduced headache frequency in patients with migraine. METHODS: Nine patients with migraine were recruited into our study. All patients received 20 cTBS sessions (bursts of 3 50-Hz TMS pulses at 200-ms intervals for 40 seconds), administered every weekday for 4 consecutive weeks. All patients kept headache diaries for 4 weeks before stimulation (baseline; T1), during stimulation (T2), and 4 weeks after stimulation (T3). The primary outcome measures were the changes of total headache and migraine days from baseline (Wilcoxon signed-rank test; T2 and T3 vs. T1). RESULTS: The number of total headache days was reduced at T2 and T3 compared with T1 [9.4 ± 6.2 days (p = 0.024) and 8.7 ± 10.1 days (p = 0.012) vs. 13.4 ± 10.1 days]. The number of migraine days was also reduced at T2 and T3 compared with T1 [2.9 ± 2.7 days (p = 0.021) and 1.0 ± 1.6 days (p = 0.008) vs. 8.6 ± 8.7 days]. CONCLUSION: Our results indicate that cTBS on the primary motor cortex might reduce the number of total headache and migraine days in patients with migraine. However, large-scale randomized controlled trials are necessary to further validate the findings.

Facilitation of the Lesioned Motor Cortex During Tonic Contraction of the Unaffected Limb Corresponds to Motor Status After Stroke.

BACKGROUND AND PURPOSE: Contraction of the muscles of the unaffected hand is associated with enhanced activation of lesioned motor cortex (ie, crossed facilitation) in some individuals after stroke. However, the association between crossed facilitation and motor function status remains unclear. We investigated whether existence of crossed facilitation corresponds to motor status of the affected upper limb after stroke. METHODS: Data were collected from 58 participants with unilateral stroke. The Fugl-Meyer assessment of upper extremity (FMA-UE) was used to evaluate motor status. Motor-evoked potentials (MEPs) were elicited from the abductor pollicis brevis (ABP) of the affected side under 3 conditions: rest, tonic contraction of the ABP of the unaffected side, or tonic contraction of the tibialis anterior of the unaffected side. RESULTS: In 28 of the 58 participants, MEPs could be elicited from the affected ABP at rest; these participants also exhibited crossed facilitation during contraction on the unaffected side. Participants with MEPs at rest exhibited higher FMA-UE scores (53.04 ± 2.59) compared with participants with absent MEP (19.83 ± 1.60; Z = -6.21). Seven participants with no MEPs at rest had MEPs with crossed facilitation; their FMA-UE scores were higher compared with the 23 who had no ABP MEP under any condition (Z = -2.66). FMA-UE scores were positively correlated with the amount of crossed facilitation during the APB task (r = 0.68) and the tibialis anterior task (r = 0.54). DISCUSSION AND CONCLUSIONS: In some participants, MEPs in the affected hand muscle were enhanced by tonic contraction of the muscles on the unaffected side even if no MEP could be evoked at rest. The degree of crossed facilitation in the affected hand muscle was correlated with the level of motor function of the affected upper limb, and the FMA-UE score could classify the presence/absence of crossed facilitation.Video abstract available for more insights from the authors (Supplemental Digital Content 1, http://links.lww.com/JNPT/A117).

Widespread inter-ictal excitability changes in patients with temporal lobe epilepsy: A TMS/MEG study.

PURPOSE: Transcranial magnetic stimulation (TMS) has been used to elucidate the altered balance between excitatory and inhibitory circuits in the motor cortex in epilepsy; however, TMS could not well assess excitability changes beyond the motor cortex. This study aimed to address the spatial profile of cortical excitability changes in patients with temporal lobe epilepsy (TLE) by using TMS and magnetoencephalography (MEG). METHODS: Eighteen patients with TLE and 18 healthy control subjects were recruited. Resting motor threshold (RMT) and intracortical inhibition (ICI) were measured to reflect motor cortical excitability by using TMS. A whole-head MEG was applied to record auditory and somatosensory evoked responses to paired-pulse stimuli. A paired-pulse inhibition (PPI) ratio, defined as the amplitude ratio between responses to the second and the first stimuli, was used to assess the auditory and somatosensory cortical excitability. A high PPI ratio suggests an increase in cortical excitability, while a low ratio indicates a decrease in excitability. RESULTS: Compared to control subjects, TLE patients exhibited increased RMT in motor cortex and higher PPI ratios for auditory P50m and somatosensory P35m responses. Notably, patients with a lower seizure frequency tended to exhibit a higher RMT or a lower P35m PPI ratio. CONCLUSIONS: Present data suggest that the cortical excitability alteration in focal epilepsy is widely distributed beyond the epileptic focus and the profiles of excitability change correlate with clinical severity in terms of seizure frequency. Combined MEG and TMS studies provide new insight into the inter-ictal cortical excitability profiles in patients with epilepsy.

Fractional anisotropy in corpus callosum is associated with facilitation of motor representation during ipsilateral hand movements.

BACKGROUND: Coactivation of primary motor cortex ipsilateral to a unilateral movement (M1(ipsilateral)) has been observed, and the magnitude of activation is influenced by the contracting muscles. It has been suggested that the microstructural integrity of the callosal motor fibers (CMFs) connecting M1 regions may reflect the observed response. However, the association between the structural connectivity of CMFs and functional changes in M1(ipsilateral) remains unclear. The purpose of this study was to investigate the relationship between functional changes within M1(ipsilateral) during unilateral arm or leg movements and the microstructure of the CMFs connecting both homotopic representations (arm or leg). METHODS: Transcranial magnetic stimulation was used to assess changes in motor evoked potentials (MEP) in an arm muscle during unilateral movements compared to rest in fifteen healthy adults. Functional magnetic resonance imaging was then used to identify regions of M1 associated with either arm or leg movements. Diffusion-weighted imaging data was acquired to generate CMFs for arm and leg areas using the areas of activation from the functional imaging as seed masks. Individual values of regional fractional anisotropy (FA) of arm and leg CMFs was then calculated by examining the overlap between CMFs and a standard atlas of corpus callosum. RESULTS: The change in the MEP was significantly larger in the arm movement compared to the leg movement. Additionally, regression analysis revealed that FA in the arm CMFs was positively correlated with the change in MEP during arm movement, whereas a negative correlation was observed during the leg movement. However, there was no significant relationship between FA in the leg CMF and the change in MEP during the movements. CONCLUSIONS: These findings suggest that individual differences in interhemispheric structural connectivity may be used to explain a homologous muscle-dominant effect within M1(ipsilateral) hand representation during unilateral movement with topographical specificity.