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Interval timing is involved in a variety of cognitive behaviors such as associative learning and decision-making. While it has been shown that time estimation is adaptive to the temporal context, it remains unclear how interval timing behavior is influenced by recent trial history. Here we found that, in mice trained to perform a licking-based interval timing task, a decrease of inter-reinforcement interval in the previous trial rapidly shifted the time of anticipatory licking earlier. Optogenetic inactivation of the anterior lateral motor cortex (ALM), but not the medial prefrontal cortex, for a short time before reward delivery caused a decrease in the peak time of anticipatory licking in the next trial. Electrophysiological recordings from the ALM showed that the response profiles preceded by short and long inter-reinforcement intervals exhibited task-engagement-dependent temporal scaling. Thus, interval timing is adaptive to recent experience of the temporal interval, and ALM activity during time estimation reflects recent experience of interval.
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Animals , Mice , Reward , Time Factors , Cognition , Learning , Decision Making , Reinforcement, PsychologyABSTRACT
OBJECTIVE@#To observe the effects of electroacupuncture (EA) on cardiac function and local field potential (LFP) in sensory and motor cortices in mice with stress cardiomyopathy (SC), and to explore the possible mechanism of EA in improving SC.@*METHODS@#Twenty-seven female C57BL/6 mice were randomized into a blank group, a model group and an EA group, 9 mice in each group. In the model group and the EA group, SC model was established by continuous intraperitoneal injection of isoproterenol (ISO) for 14 days. At the same time of modeling, EA was applied at "Neiguan" (PC 6) and "Shenmen" (HT 7) in the EA group, with disperse-dense wave, in frequency of 2 Hz/15 Hz, 15 min each time, once a day for 14 days. After intervention, the total movement distance, the number of crossing grid and the number of crossing central grid of open field test within 5 minutes were observed; the left ventricular function indexes (left ventricular diameter of end-diastole [LVIDd], left ventricular diameter of end-systole [LVIDs], left ventricular volume of end-diastole [LVEDV], left ventricular volume of end-systole [LVESV], ejection fraction [EF] and fraction shortening [FS]) were detected by echocardiography; the changes in ST-segment amplitude and PR interval of electrocardiogram were observed; the morphology of myocardial tissue was observed by HE staining; the serum levels of cortisol (CORT), cardiac troponin T (cTnT) and brain natriuretic peptide (BNP) were detected by ELISA; the changes of LFP in sensory and motor cortices were recorded by Plexon multi-channel acquisition system.@*RESULTS@#Compared with the blank group, in the model group, the total movement distance, the number of crossing grid and the number of crossing central grid of open field test were decreased (P<0.05); LVIDd, LVIDs, LVEDV and LVESV were increased (P<0.05), EF and FS were decreased (P<0.05); ST-segment amplitude was increased (P<0.05) and PR interval was prolonged (P<0.05); irregular myocardial fiber arrangement, interstitial edema and inflammatory cell infiltration were observed; the serum levels of CORT, cTnT and BNP were increased (P<0.05); in the sensory cortex, the ratios of delta, theta, alpha and beta frequency bands were increased (P<0.05), the maximum energy spectrum of theta and beta frequency bands was increased (P<0.05), the power spectral density (PSD) of delta, theta, alpha, beta and gamma frequency bands was increased (P<0.05); in the motor cortex, the ratios of delta, theta, alpha and beta frequency bands were increased (P<0.05), the maximum energy spectrum as well as PSD of delta, theta, alpha, beta and gamma frequency bands were increased (P<0.05). Compared with model group, in the EA group, the total movement distance, the number of crossing grid and the number of crossing central grid of open field test were increased (P<0.05); LVIDd, LVIDs, LVEDV and LVESV were decreased (P<0.05), EF and FS were increased (P<0.05); ST-segment amplitude was decreased (P<0.05), and the PR interval was shortened (P<0.05); myocardial fiber injury and inflammatory cell infiltration were reduced; the serum levels of CORT, cTnT and BNP were decreased (P<0.05); in the sensory cortex, the ratios of theta, alpha and beta frequency bands were decreased (P<0.05), the ratio of gamma frequency band was increased (P<0.05), the maximum energy spectrum of theta frequency band as well as the PSD of theta, alpha, beta and gamma frequency bands were decreased (P<0.05); in the motor cortex, the ratios of theta, alpha and beta frequency bands were decreased (P<0.05) and the ratio of gamma frequency band was increased (P<0.05), the maximum energy spectrum of delta frequency band was increased (P<0.05), the maximum energy spectrum of theta frequency band as well as the PSD of theta and gamma frequency bands were decreased (P<0.05).@*CONCLUSION@#EA can improve cardiac function in mice with stress cardiomyopathy, and its mechanism may be related to the regulation of local field potentials in sensory and motor cortices.
Subject(s)
Female , Mice , Animals , Electroacupuncture , Takotsubo Cardiomyopathy , Motor Cortex , Mice, Inbred C57BL , MyocardiumABSTRACT
Objectives: The aim of this article is to explain the detailed methodology to record Motor evoked potential (MEP) and somatosensory evoked potential (SSEP) in adult albino Wistar rat, male (200–250 g) which has not been defined previously. Materials and Methods: We have standardised recording of both MEP and SSEP in these rats under anaesthesia on ADI digital polyrite system. Results: Evoked potentials have been widely studied in spinal cord injured patients to estimate the degree of injury and to establish a predictive measure of functional recovery. MEPs and SSEPs, arising from the motor cortex or peripheral nerve and generated either by direct electrical stimulation or by transcranial magnetic stimulation, have been advocated as a reliable indicator of descending and ascending pathway integrity. In the rat brain, there is a physical overlap between the motor and somatosensory cortex. Hence, our objective was to identify the exact area for stimulation in the cortex where we could record maximum response with the application of minimum electrical stimulation. Conclusion: The recording of MEP and SSEP together provides a powerful neurological technique to monitor the tracts of the spinal cord.
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ABSTRACT BACKGROUND AND OBJECTIVES: Fibromyalgia (FM) is a chronic widespread musculoskeletal pain resulting in central sensitization of nociceptive signaling. Transcranial direct current stimulation (tDCS) over the left motor cortex (M1) is a non-invasive neuromodulation technique indicated for a broad range of chronic pain disorders, including FM. Studies suggest that left and right M1 (contralateral and ipsilateral hemisphere of tDCS stimulation) are modulated. But it is necessary to clarify the differences in clinical pain perception comparing the right and left side of the body. This study aimed to evaluate the pain-related difference between right-left side of the body after five sessions of anodal tDCS in women with FM. METHODS: A double-blinded, parallel, randomized, sham-controlled trial with 30 women with FM was performed. Five sessions of anodal C3 and cathodal supraorbital (Fp2) tDCS were conducted (2 mA for 20 min). Pain, impact of FM and anxiety were evaluated. No statistically significant three-way interaction between time, stimulation type and body side were found. RESULTS: Active-tDCS showed significant improvement in pain, but impact of FM and anxiety did not show significant improvement. CONCLUSION: Five sessions of anodal tDCS over the left M1 improves pain in women with FM, however there was no difference between right-left body sides.
RESUMO JUSTIFICATIVA E OBJETIVOS: A fibromialgia (FM) é uma dor musculoesquelética crônica generalizada que resulta na sensibilização central da sinalização nociceptiva. A estimulação transcraniana de corrente contínua (eTCC) sobre o córtex motor esquerdo (M1) é uma técnica de neuromodulação não invasiva indicada para uma ampla gama de distúrbios de dor crônica, incluindo a FM. Estudos sugerem a modulação do M1 esquerdo e direito (hemisfério contralateral e ipsilateral da eTCC). Mas é necessário esclarecer as diferenças na percepção clínica da dor comparando os lados direito e esquerdo do corpo. Este estudo teve como objetivo avaliar a diferença relacionada à dor entre o lado direito e esquerdo do corpo após cinco sessões de eTCC anodal em mulheres com FM. MÉTODOS: Foi realizado um estudo duplo-cego, paralelo, randomizado e controlado por sham com 30 mulheres com FM. Foram realizadas cinco sessões de eTCC anodais C3 e supraorbitais catodais (Fp2) (2 mA por 20 min). Foram avaliados a dor, o impacto da FM e a ansiedade. Não foi encontrada nenhuma interação de três vias estatisticamente significativa entre tempo, tipo de estimulação e lado do corpo. RESULTADOS: A eTCC-Ativa mostrou uma melhora significativa na dor, mas o impacto da FM e da ansiedade não mostrou uma melhora significativa. CONCLUSÃO: Cinco sessões de eTCC anodal sobre o M1 esquerdo melhoram a dor nas mulheres com FM, entretanto não houve diferença entre os lados direito e esquerdo do corpo.
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Objective:To observe any effect of magnetic stimulation of the primary motor cortex and sacral nerve roots on urinary retention after spinal cord injury.Methods:Forty patients experiencing urine retention after a spinal cord injury were randomly divided into an experimental group and a control group, each of 20. Both groups received conventional treatment and repeated magnetic stimulation of the roots of the sacral nerve. The experimental group also received repeated magnetic stimulation of the bilateral primary motor cortices (M1 region). Bladder capacity and pressure indices, residual urine volume and life quality were evaluated in both groups before and after 8 weeks of treatment.Results:After the treatment, the average maximum bladder pressure, first sensation capacity, residual urine volume and life quality score of both groups had improved significantly, but the improvements in average first sensation capacity, residual urine volume and life quality score of the experimental group were significantly greater than those of the control group. There was, however, no significant difference in the groups′ average maximum bladder pressure after the treatment.Conclusion:Magnetic stimulation of the primary motor cortex and sacral nerve roots can significantly improve the sensory function of the bladder, reduce residual urine volume and improve the life quality of persons experiencing urinary retention after a spinal cord injury.
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Excessive theta (θ) frequency oscillation and synchronization in the basal ganglia (BG) has been reported in elderly parkinsonian patients and animal models of levodopa (L-dopa)-induced dyskinesia (LID), particularly the θ oscillation recorded during periods when L-dopa is withdrawn (the off L-dopa state). To gain insight into processes underlying this activity, we explored the relationship between primary motor cortex (M1) oscillatory activity and BG output in LID. We recorded local field potentials in the substantia nigra pars reticulata (SNr) and M1 of awake, inattentive resting rats before and after L-dopa priming in Sham control, Parkinson disease model, and LID model groups. We found that chronic L-dopa increased θ synchronization and information flow between the SNr and M1 in off L-dopa state LID rats, with a SNr-to-M1 flow directionality. Compared with the on state, θ oscillational activity (θ synchronization and information flow) during the off state were more closely associated with abnormal involuntary movements. Our findings indicate that θ oscillation in M1 may be consequent to abnormal synchronous discharges in the BG and support the notion that M1 θ oscillation may participate in the induction of dyskinesia.
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Objective:To investigate the changes of metabolite concentration in the precentral gyrus (primary motor cortex, M1) in spinal cord injury (SCI) patients. Methods:From December, 2018 to October, 2019, 20 SCI patients and 15 healthy controls were scaned with magnetic resonance spectroscopy to measure the concentrations of N-acetylaspartate (NAA), choline (Cho), creatine (Cr) and myo-inositol (MI) in region of interest (ROI) of left M1. Results:Concentration of MI was more in the patients than in the controls (t = 3.745, P < 0.01). There was no significant difference in the concentrations of NAA, Cho and Cr, as well as the ratios of NAA/Cr, Cho/Cr, Cho/NAA between the patients and the controls (t < 1.431, P > 0.05). Conclusion:There may be hyperplasia of glial cells in M1 of SCI patients, indicating compensatory repair in cerebral motor cortex.
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OBJECTIVE@#To explore the possible underlying mechanism by investigating the effect of electroacupuncture (EA) treatment on the primary motor cortex and striatum in a unilateral 6-hydroxydopamine (6-OHDA) induced rat Parkinson's disease (PD) model.@*METHODS@#Male Sprague-Dawley rats were randomly divided into sham group (n=16), model group (n=14), and EA group (n=14). EA stimulation at Dazhui (GV 14) and Baihui (GV20) was applied to PD rats in the EA group for 4 weeks. Behavioral tests were conducted to evaluate the effectiveness of EA treatment. Metabolites were detected by 7.0 T proton nuclear magnetic resonance.@*RESULTS@#Following 4 weeks of EA treatment in PD model rats, the abnormal behavioral impairment induced by 6-OHDA was alleviated. In monitoring changes in metabolic activity, ratios of myoinositol/creatine (Cr) and N-acetyl aspartate (NAA)/Cr in the primary motor cortex were significantly lower at the injected side than the non-injected side in PD rats (P=0.024 and 0.020). The ratios of glutamate + glutamine (Glx)/Cr and NAA/Cr in the striatum were higher and lower, respectively, at the injected side than the non-injected side (P=0.046 and 0.008). EA treatment restored the balance of metabolic activity in the primary motor cortex and striatum. In addition, the taurine/Cr ratio and Glx/Cr ratio were elevated in the striatum of PD model rats compared to sham-lesioned rats (P=0.026 and 0.000). EA treatment alleviated the excessive glutamatergic transmission by down-regulating the striatal Glx/Cr ratio (P=0.001). The Glx/Cr ratio was negatively correlated with floor plane spontaneous locomotion in PD rats (P=0.027 and P=0.0007).@*CONCLUSIONS@#EA treatment is able to normalize the metabolic balance in the primary motor cortex and striatum of PD rats, which may contribute to its therapeutic effect on motor deficits. The striatal Glx/Cr ratio may serve as a potential indicator of PD and a therapeutic target of EA treatment.
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Background:The present study aimed to evaluate the effects of EE on the morphology of pyramidal neuron at the motor cortex of diabetic and stressed rats.Methods and materials:Male Wistar rats were grouped into Normal Control (NC), Vehicle Control (VC), Diabetes (D), Diabetes + Stress (D+S), Diabetes + Environmental Enrichment (D+EE) and Diabetes + Stress +Environmental Enrichment (D+S+EE) (n=8). Hyperglycemia was induced in Westar rats using streptozotocin (40mg/kg; ip). Blood sugar levels and body weight was measured at regular intervals to monitor the development of hyperglycemia. All experimental groups were housed in standard cages throughout the experiment. Rats in groups D+S and D+S+EE were transferred into space restrained cages for 6 hours daily. D+S+EE group were transferred into EE cages immediately after the space restrained session for subsequent 6 hours daily. On day 30, all rats were sacrificed and brains were harvested and prepared for rapid Golgi staining protocol. Dendritic branchings and dendriticintersections of the motor cortex neurons were quantitated using a camera lucida attached to Biolux research microscope. Data was analyzed using ANOVA with Bonferroni’s test.
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Objective: to identify whether maternal separation during breastfeeding (MSDB) affects the cellular count in different rat brain areas. The continuous mother-child interaction,adjusts and modulates the offspring behavioral response to environmental stimuli and also affects their development and homeostasis. Morphological and physiological changes in the offspring brains have been observed, including cell count changes in different brain areas with differences between males and females. Materials and methods: this study compared albino Wistar rats in a protocol of MSDB with a control group. Brain tissue was fixed with paraformaldehyde, cut in cryostat and either stained with Hematoxylin-Eosin (H&E) or processed for immunohistochemistry against glial fibrillary acidic protein (GFAP). All sections were analyzed using a cell count protocol including statistical analysis with Students T test at a significance level of P ≤0.05.Results: the MSDB group of male subjects presented higher GFAP-marked cell count in primary motor cortex and hippocampus; while female subjects, showed less GFAPmarked cell count in these same areas. Conclusions: MSDB produces sex-specific changes in the number of glial cells especially in the primary motor cortex, this finding may be considered as associated factor of alterations in motor responses to stress in these subjects, in addition to other known causes such as the Hypothalamic-Pituitary- Adrenal Axis dysfunction..(AU)
Objetivo: identificar si la separación materna durante la lactancia (MSDB) afecta el conteo celular en cortezas motoras y otras áreas del cerebro de la rata. La interacción continua entre la madre y su hijo, ajusta y modula la respuesta comportamental de las crías hacia estímulos ambientales, afectando además su desarrollo y homeostasis. Cambios morfológicos y fisiológicos han sido descritos en la descendencia, incluyendo diferencias en conteos celulares de varias áreas de la corteza cerebral. Materiales y métodos: este estudio se compararon ratas Albino Wistar bajo un protocolo de MSDB contra un grupo control. El tejido cerebral fue fijado con paraformaldehido, cortado en criostato, y tratado con tinción Hematoxilina-Eosina (H&E) o procesado con inmunohistoquimica contra proteína acida glíal fibrilar (GFAP). Todas las secciones fueron analizadas usando un protocolo de conteo que incluyo análisis estadístico con el test de T de Student con significancia a nivel de P ≤0.05. Resultados: el grupo de machos que tuvo MSDB presentó mayor conteo de células marcadas contra GFAP en las cortezas motoras primarias y el hipocampo; mientras que las hembras con MSDB, mostraron menor conteo de células marcadas contra GFAP en estas mismas áreas. Conclusión: la MSDB produce cambios específicos de acuerdo al sexo del sujeto, en el número de células gliales especialmente en las cortezas motoras primarias, este hallazgo puede ser considerado como causante parcial de las alteraciones en las respuestas motoras a estrés en estos sujetos, además de otras causas conocidas como la disfunción del eje Hipotálamo-Pituitario-Adrenal (HPA)..(AU)
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Animals , Maternal NutritionABSTRACT
RESUMEN La parálisis pseudoperiférica es una presentación infrecuente del ataque cerebrovascular (ACV) isquémico, que suele llevar a un diagnóstico erróneo de patología de nervio periférico. Se caracteriza por una presentación clínica consistente en paresia de la mano o de un grupo de dedos y alteración de la sensibilidad que puede simular el compromiso de un nervio periférico. Se reporta el caso clínico de un paciente que cursó con parálisis pseudoperiférica, con compromiso motor predominantemente cubital asociado a hipoestesia multimodal en la región hipotenar, lo cual ilustrando la dificultad de la localización topográfica para explicar el compromiso motor y sensitivo por un síndrome mononeuropático, troncular, radicular o medular. Se resalta la importancia de una adecuada evaluación semiológica, que permita hacer aproximaciones diagnósticas acertadas para dar un manejo adecuado de acuerdo con el estudio topográfico en las patologías neurológicas.
SUMMARY Pseudo-peripheral palsy is an infrequent presentation of ischemic stroke, which often leads to a misdiagnosis of peripheral nerve pathology. It is characterized by palsy of the hand or a group of fingers and altered sensitivity which can simulate peripheral nerve damage. We report a case of a patient who had pseudo-peripheral palsy with predominantly ulnar motor involvement, associated with multimodal hypoesthesia in the hypothenar region; illustrating the difficulty of topographic localization to explain motor and sensory involvement by a mononeuropathic, radicular or spinal syndrome. We highlight the importance of an adequate semiological evaluation to accurately diagnose and manage these pathologies.
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Paralysis , Stroke , Diagnosis, Differential , Motor CortexABSTRACT
Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that modulates cortical excitability and influences cognition. The role of the primary motor cortex (M1) in cognition is controversial. Here, we investigated the offline effects of anodal and sham tDCS over M1 on cognitive tasks that require comparable motor skills, but different levels of working memory and attention. Twenty healthy young female adults received anodal tDCS and sham tDCS to the M1 on two separate testing days in a counter balanced order. The cognitive functions outcome variables were the response time from the Attention Switching Task (AST) and Motor Screening Task (MST) tests using the Cambridge Neuropsychological Test Automated Battery before and after the anodal/sham tDCS. Anodal tDCS significantly improved AST response times from baseline in congruent and incongruent condition and MST mean correct latency (all p < 0.05). There was a significant difference for AST tasks variable include AST Switching cost (mean, correct), AST Mean correct latency, in congruent, incongruent, blocks 3, 5 (non-switching blocks), block 7 (switching block) (p < 0.01) and MST mean latency (p < 0.05) between anodal and sham conditions. These results indicate that tDCS is a promising tool to an improvement in response time in task related attention and motor speed. However, this study warrants further research to determine the long-term effect on other cognitive functions and in different age and gender groups.
Subject(s)
Adult , Female , Humans , Brain , Cognition , Mass Screening , Memory, Short-Term , Motor Cortex , Motor Skills , Neuropsychological Tests , Reaction Time , Transcranial Direct Current StimulationABSTRACT
Motor timing is an important part of sensorimotor control. Previous studies have shown that beta oscillations embody the process of temporal perception in explicit timing tasks. In contrast, studies focusing on beta oscillations in implicit timing tasks are lacking. In this study, we set up an implicit motor timing task and found a modulation pattern of beta oscillations with temporal perception during movement preparation. We trained two macaques in a repetitive visually-guided reach-to-grasp task with different holding intervals. Spikes and local field potentials were recorded from microelectrode arrays in the primary motor cortex, primary somatosensory cortex, and posterior parietal cortex. We analyzed the association between beta oscillations and temporal interval in fixed-duration experiments (500 ms as the Short Group and 1500 ms as the Long Group) and random-duration experiments (500 ms to 1500 ms). The results showed that the peak beta frequencies in both experiments ranged from 15 Hz to 25 Hz. The beta power was higher during the hold period than the movement (reach and grasp) period. Further, in the fixed-duration experiments, the mean power as well as the maximum rate of change of beta power in the first 300 ms were higher in the Short Group than in the Long Group when aligned with the Center Hit event. In contrast, in the random-duration experiments, the corresponding values showed no statistical differences among groups. The peak latency of beta power was shorter in the Short Group than in the Long Group in the fixed-duration experiments, while no consistent modulation pattern was found in the random-duration experiments. These results indicate that beta oscillations can modulate with temporal interval in their power mode. The synchronization period of beta power could reflect the cognitive set maintaining working memory of the temporal structure and attention.
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Nerve conduction block, proprioceptive loss and phantom limb pain after amputation may result in brain plasticity. In addition, the mirror neuron system of amputees plays an important role in their learning ability. However, there are few studies on adaptability of the motor cortex in upper limb amputees, and the central mechanism of motor control and learning of the residual limb or prosthesis needs more studies.
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BACKGROUND AND PURPOSE: Freezing of gait (FOG) is a frustrating problem in Parkinson's disease (PD) for which there is no effective treatment. Our aim was to find brain stimulation areas showing greater responses for reducing FOG. METHODS: Twelve PD patients with FOG were selected for inclusion. We explored the therapeutic effect of repetitive transcranial magnetic stimulation (rTMS) in the supplementary motor area (SMA) and the motor cortex (MC). We measured the number of steps, completion time, and freezing episodes during the stand-walk-sit test before and after rTMS treatment. We also tested freezing episodes in two FOG-provoking tasks. RESULTS: There was a trend for a greater reduction in freezing episodes with SMA stimulation than MC stimulation (p=0.071). FOG was significantly improved after SMA stimulation (p < 0.05) but not after MC stimulation. CONCLUSIONS: Our study suggests that the SMA is a more-appropriate target for brain stimulation when treating PD patients with FOG. This study provides evidence that stimulating the SMA using rTMS is beneficial to FOG, which might be useful for future developments of therapeutic strategies.
Subject(s)
Humans , Brain , Freezing , Gait , Motor Cortex , Parkinson Disease , Transcranial Magnetic Stimulation , WeatherABSTRACT
Background: Previous studies from animal models have shown that pre-synapticNMDA receptors (preNMDARs) are present in the cortex, but the role of inhibition mediated bypreNMDARs during epileptogenesis remains unclear. In this study, we wanted to observe thechanges in GABAergic inhibition through preNMDARs in sensory-motor and visual corticalpyramidal neurons after pilocarpine-induced status epilepticus.Methods: Using a pilocarpine-induced epileptic mouse model, sensory-motor and visualcortical slices were prepared, and the whole-cell patch clamp technique was used to recordspontaneous inhibitory post-synaptic currents (sIPSCs).Results: The primary finding was that the mean amplitude of sIPSC from the sensorymotorcortex increased significantly in epileptic mice when the recording pipette contained MK-801 compared to control mice, whereas the mean sIPSC frequency was not significantly different,indicating that post-synaptic mechanisms are involved. However, there was no significant presynapticinhibition through preNMDARs in the acute brain slices from pilocarpine-inducedepileptic mice.Conclusion: In the acute case of epilepsy, a compensatory mechanism of post-synapticinhibition, possibly from ambient GABA, was observed through changes in the amplitude withoutsignificant changes in the frequency of sIPSC compared to control mice. The role of preNMDARmediatedinhibition in epileptogenesis during the chronic condition or in the juvenile stagewarrants further investigation.
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@#This is the first Indian case report of a biopsy proven temporal arteritis that presented as acute ischemic stroke. The 60 year old woman presented with an isolated pure motor flaccid fractional weakness of the left distal hand, as a rare stroke chameleon due to isolated infarction of the ‘hand motor cortex’ area. The hand motor cortex infarction masquerades as ‘pseudoperipheral palsy’.
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Objective To investigate the effect of high frequency (10 Hz),low frequency (1 Hz) and theta burst stimulation (TBS) mode of repetitive transcranial magnetic stimulation (rTMS) on the recovery of motor function in hemiplegic patients following acute ischemic stroke.Methods Seventy-two patients with hemiplegia after acute ischemic stroke were randomly grouped with the random number table.They were treated with low frequency (n=18),high frequency (n=18),and TBS (n=18) rTMS or sham stimulation (control group,n=18),once a day,for 2 weeks.Fugl-Meyer Assessment (FMA) and National Institutes of Health Stroke Scale (NIHSS) were used to evaluate neurological function in all patients before rTMS treatment (on the day before the first treatment) and after treatment (on the day after the last treatment).Results After treatment,the FMA and NIHSS scores in the 4 groups were significantly improved compared with before treatment (all P<0.05).After rTMS treatment,the FMA and NIHSS scores were improved significantly in the high frequency group,low frequency group and TBS group compare with the control group (all P<0.05).There were no significant differences among all the treatment groups.Conclusion sHigh frequency,low frequency and TBS rTMS can improve the recovery of motor function in hemiplegic patients following acute ischemic stroke.There were no significant differences among all the treatment modes.
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Objective To identify Chinese character writing related cortex (WRC) and its relationship with hand motor cortical areas. Methods Ten native Chinese-speaking, right-hand volunteers were recruited in the study. NTMS mapping was conducted during picture naming task. The WRC were mapped based on nTMS-induced impairment of Chinese character writing. The extent and area of WRC was calculated. The right-hand motor representations were mapped while motor-evoked potentials were produced under nTMS stimulation. EMG data and coordinates of positive stimulus were recorded. The relationship between WRC and hand motor cortex (HMC) was analyzed on the basis of area comparison and distance calculation. Results The cortical areas related to Chinese character writing were mapped successfully in all subjects by nTMS. WRC was primarily centered in left posterior middle frontal gyrus (pMFG) (86%,55/64). The mean WRC area (161.03 mm2 ±62.58mm2) was significantly smaller than the mean HMC area (589.50 mm2±227.34mm2) (P<0.001). The WRC and HMC were not conjoined or overlapped in the dominant hemisphere. The distance between those two was 12.58mm±2.71mm. Conclusions NTMS can provide reliable assistance in mapping WRC areas. The WRC is relatively fixed and centralized in pMFG but is not overlapped with the HMC.
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Abstract Aims the aim of this study was to verify the effects of different intensities of locomotor exercise on corticospinal excitability. Methods 18 healthy subjects (27.6 ± 6.5 years,) participated in a design study of three different exercise protocols on a cycle ergometer: (i) 10 min at 75% Wmax (high intensity); (ii) 15min at 60% Wmax (moderate intensity) or (iii) 30 min at 45% Wmax (low intensity). The protocols of lower body cycling were assigned in random order in separate sessions. A control session was done with subjects at rest. Corticospinal excitability was assessed before (baseline) and every 5 min for 15min after the end of exercise/rest (time: 0, 5, 10 and 15) by measurement of the motor evoked potential (MEP) elicited by transcranial magnetic stimulation in the relaxed first-dorsal interosseus muscle. Results Compared to the resting session, a significant decrease (64%) in the motor evoked potential amplitudes was found only in the session of exercise of high intensity. This result seems depend on the level of physical activity of subject. No change was found after rest, low and moderate exercises. Conclusions These findings suggest that changes in the corticospinal excitability depend on exercise intensity and level of physical activity of subjects.(AU)