• Title/Summary/Keyword: Cortical excitability

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Transcranial Magnetic Stimulation in Gilles de la Tourette Syndrome (뚜렛 증후군에서의 경두개 자기자극술)

  • Lee, Moon-Soo
    • Korean Journal of Psychosomatic Medicine
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    • v.18 no.1
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    • pp.3-10
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    • 2010
  • Gilles de la Tourette syndrome is a chronic motor and vocal tic disorder of childhood onset. Abnornmalities in basal ganglia-thalamo-cortical circuits may play an important role in the pathophysiology underlying the involuntary tics. It is often complicated by comorbid attention-deficit/hyperactivity disorder or obsessive-compulsive disorder. Transcranial magnetic stimulation(TMS) is a neurophysiologic technique with research ap-plication. As there is good evidence that this technique can modify cortical activity, repetitive TMS is also used for treatment to change the cortical excitability and therefore affect underlying interconnected cortical-sub-cortical loop. We reviewed the neurophysiologic parameters and the clinical applicability of TMS and rTMS.

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A Systematic Review of Cortical Excitability during Dual-Task in Post-Stroke Patients

  • Soyi Jung;Chang-Sik An
    • Physical Therapy Rehabilitation Science
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    • v.13 no.2
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    • pp.213-222
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    • 2024
  • Objective: Stroke is a leading cause of disability worldwide, often leaving survivors with significant cognitive and motor impairments. Dual-task (DT), which involves performing cognitive and motor tasks simultaneously, can influence brain activation patterns and functional recovery in stroke patients. Design: A systematic review Methods: Following PRISMA guidelines, databases including MEDLINE, CINAHL, Embase, and Web of Science were searched for studies assessing cortical activation via functional near-infrared spectroscopy (fNIRS) during DT performance in stroke patients. Studies were selected based on predefined eligibility criteria, focusing on changes in hemodynamic responses and their correlation with task performance. Results: Eight studies met the inclusion criteria. Findings indicate that DT leads to increased activation in the prefrontal cortex (PFC), premotor cortex (PMC), and posterior parietal cortex (PPC), suggesting an integrated cortical response to managing concurrent cognitive and motor demands. However, increased activation did not consistently translate to improved functional outcomes, highlighting the complex relationship between brain activation and rehabilitation success. Conclusions: DT interventions may enhance cortical activation and neuroplasticity in post-stroke patients, but the relationship between increased brain activity and functional recovery remains complex and requires further investigation. Tailored DT programs that consider individual neurophysiological and functional capacities are recommended to optimize rehabilitation outcomes.

Neuromodulation for Insomnia Management (불면증 치료법으로서의 뉴로모듈레이션)

  • Yoon, Ho-Kyoung
    • Sleep Medicine and Psychophysiology
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    • v.28 no.1
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    • pp.2-5
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    • 2021
  • Hyperarousal or increased brain excitability is thought to play a key role in the pathophysiology of insomnia. Neuromodulation techniques are emergent complementary therapies for insomnia and can improve sleep by modulating cortical excitability. A growing body of literature support the idea that neuromodulation can be effective in improving sleep or treating insomnia. Recent evidence has revealed that neuromodulation methods can improve objective and subjective sleep measures in individuals with insomnia, although effects vary according to protocol. Different mechanisms of action might explain the relative efficacy of neuromodulation techniques on sleep outcomes. Further research testing different stimulation parameters, replicating existing protocols, and adding standardized sleep-related outcomes could provide further evidence on the clinical utility of neuromodulation techniques.

Effect of rTMS on Motor Sequence Learning and Brain Activation : A Preliminary Study (반복적 경두부 자기자극이 운동학습과 뇌 운동영역 활성화에 미치는 영향 : 예비연구)

  • Park, Ji-Won;Kim, Jong-Man;Kim, Yun-Hee
    • Physical Therapy Korea
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    • v.10 no.3
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    • pp.17-27
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    • 2003
  • Repetitive transcranial magnetic stimulation (rTMS) modulates cortical excitability beyond the duration of the rTMS trains themselves. Depending on rTMS parameters, a lasting inhibition or facilitation of cortical excitability can be induced. Therefore, rTMS of high or low frequency over motor cortex may change certain aspects of motor learning performance and cortical activation. This study investigated the effect of high and low frequency subthreshold rTMS applied to the motor cortex on motor learning of sequential finger movements and brain activation using functional MRI (fMRI). Three healthy right-handed subjects (mean age 23.3) were enrolled. All subjects were trained with sequences of seven-digit rapid sequential finger movements, 30 minutes per day for 5 consecutive days using their left hand. 10 Hz (high frequency) and 1 Hz (low frequency) trains of rTMS with 80% of resting motor threshold and sham stimulation were applied for each subject during the period of motor learning. rTMS was delivered on the scalp over the right primary motor cortex using a figure-eight shaped coil and a Rapid(R) stimulator with two Booster Modules (Magstim Co. Ltd, UK). Functional MRI (fMRI) was performed on a 3T ISOL Forte scanner before and after training in all subjects (35 slices per one brain volume TR/TE = 3000/30 ms, Flip angle $60^{\circ}$, FOV 220 mm, $64{\times}64$ matrix, slice thickness 4 mm). Response time (RT) and target scores (TS) of sequential finger movements were monitored during the training period and fMRl scanning. All subjects showed decreased RT and increased TS which reflecting learning effects over the training session. The subject who received high frequency rTMS showed better performance in TS and RT than those of the subjects with low frequency or sham stimulation of rTMS. In fMRI, the subject who received high frequency rTMS showed increased activation of primary motor cortex, premotor, and medial cerebellar areas after the motor sequence learning after the training, but the subject with low frequency rTMS showed decreased activation in above areas. High frequency subthreshold rTMS on the motor cortex may facilitate the excitability of motor cortex and improve the performance of motor sequence learning in normal subject.

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Transcranial magnetic stimulation parameters as neurophysiological biomarkers in Alzheimer's disease

  • Lee, Juyoun;Lee, Ae Young
    • Annals of Clinical Neurophysiology
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    • v.23 no.1
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    • pp.7-16
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    • 2021
  • Transcranial magnetic stimulation (TMS) is a safe and noninvasive tool for investigating the cortical excitability of the human brain and the neurophysiological functions of GABAergic, glutamatergic, and cholinergic neural circuits. Neurophysiological biomarkers based on TMS parameters can provide information on the pathophysiology of dementia, and be used to diagnose Alzheimer's disease and differentiate different types of dementia. This review introduces the basic principles of TMS, TMS devices and stimulating paradigms, several neurophysiological measurements, and the clinical implications of TMS for Alzheimer's disease.

Repetitive Transcranial Magnetic Stimulation Combined with Task Oriented Training to Improve Upper Extremity Function After Stroke

  • Kim, Myoung-Kwon
    • Journal of Magnetics
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    • v.19 no.2
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    • pp.170-173
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    • 2014
  • The purpose of the present study was to investigate the effect of repetitive transcranial magnetic stimulation (rTMS) in conjunction with task oriented training, on cortical excitability and upper extremity function recovery in stroke patients. This study was conducted with 31 subjects who were diagnosed as a hemiparesis by stroke. Participants in the experimental (16 members) and control groups (15 members) received rTMS and sham rTMS, respectively, during a 10 minutes session, five days per week for four weeks, followed by task oriented training during a 30 minutes session, five days per week for four weeks. Motor cortex excitability was performed by motor evoked potential and upper limb function was evaluated by motor function test. Both groups showed a significant increment in motor function test and amplitude, latency in motor evoked potential compared to pre-intervention (p < 0.05). A significant difference in post-training gains for the motor function test, amplitude in motor evoked potential was observed between the experimental group and the control group (p < 0.05). The findings of the current study demonstrated that incorporating rTMS in task oriented training may be beneficial in improving the effects of stroke on upper extremity function recovery.

Comparison of Cortical Activation between Concentric and Eccentric Exercise: A Pilot fMRI Study (기능적 자기공명영상을 이용한 구심성 및 원심성 근 수축에 따른 뇌 활성도 분석)

  • Kim, Chung-Sun;Kim, Joong-Hwi;Park, Min-Kyu;Park, Ji-Won
    • The Journal of Korean Physical Therapy
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    • v.22 no.2
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    • pp.25-30
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    • 2010
  • Purpose: Behavior and movement are accomplished by voluntary contractions of skeletal muscles. There are three types of muscle contractions: concentric, isometric and eccentric. The aim of our study was to determine whether there is a difference in the cortical activation pattern between concentric contraction and eccentric contraction of the wrist extensor muscle. Methods: Four healthy right-handed volunteers without any previous history of physical or neurological illness were recruited. fMRI scanning was done during 4 repeated blocks of concentric and eccentric exercise of the wrist joint. Subjects exercised for 12 seconds and then rested for 12 seconds before beginning the second set of exercises. To determine the excitability of cortical neurons during exercise, voxel count and intensity index were analyzed. Results: For right hand movements, when concentric contractions of the right wrist were done, only the left primary motor area was activated. In contrast, during eccentric contraction, both the primary motor area and secondary motor area were activated. For left hand movements, both concentric and eccentric contractions induced only the supplementary motor cortex and the contralateral primary motor cortex. Conclusion: During eccentric contractions, both the primary motor area and secondary motor area are activated in ipsilateral and contralateral brain areas. Thus, eccentric contractions require more complex and difficult movements than concentric contractions do.

Neuroprotective Effect of Taurine against Oxidative Stress-Induced Damages in Neuronal Cells

  • Yeon, Jeong-Ah;Kim, Sung-Jin
    • Biomolecules & Therapeutics
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    • v.18 no.1
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    • pp.24-31
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    • 2010
  • Taurine, 2-aminoethanesulfonic acid, is an abundant free amino acid present in brain cells and exerts many important biological functions such as anti-convulsant, modulation of neuronal excitability, regulation of learning and memory, anti-aggressiveness and anti-alcoholic effects. In the present study, we investigated to explore whether taurine has any protective actions against oxidative stress-induced damages in neuronal cells. ERK I/II regulates signaling pathways involved in nitric oxide (NO) and reactive oxygen species (ROS) production and plays a role in the regulation of cell growth, and apoptosis. We have found that taurine significantly inhibited AMPA induced cortical depolarization in the Grease Gap assays using rat cortical slices. Taurine also inhibited AMPA-induced neuronal cell damage in MTT assays in the differentiated SH-SY5Y cells. When the neuronal cells were treated with $H_2O_2$, levels of NO were increased; however, taurine pretreatment decreased the NO production induced by $H_2O_2$ to approximately normal levels. Interestingly, taurine treatment stimulated ERK I/II activity in the presence of AMPA or $H_2O_2$, suggesting the potential role of ERK I/II in the neuroprotection of taurine. Taken together, taurine has significant neuroprotective actions against AMPA or $H_2O_2$ induced damages in neuronal cells, possibly via activation of ERK I/II.

Effects of Action Observation Training Combied with Auditory Cueing on Gait Ability in Patients with Stroke: a Preliminary Pilot Study

  • Kim, Hyeong-Min;Son, Sung-Min;Ko, Yu-Min
    • The Journal of Korean Physical Therapy
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    • v.34 no.3
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    • pp.98-103
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    • 2022
  • Purpose: New therapeutic approaches have emerged to improve gait ability in patients with brain damage, such as action observation learning (AOT), auditory cueing, motor imagery etc. We attempted to investigate the effects of AOT with auditory cueing (AOTAC) on gait function in patients with stroke. Methods: The eighteen stroke patients with a unilateral hemiparesis were randomly divided into three groups; the AOTAC, AOT, and control groups. The AOTAC group (n=8) received training via observing a video that showed normal gait with sound of footsteps as an auditory cue; the AOT group (n=6) receive action observation without auditory stimulation; the control group (n=5) observed the landscape video image. Intervention time of three groups was 30 minutes per day, five times a week, for four weeks. Gait parameters, such as cadence, velocity, stride length, stance phase, and swing phase were collected in all patients before and after each training session. Results: Significant differences were observed among the three groups with respect to the parameters, such as cadence, velocity, stride length, and stance/swing phase. Post-hoc analysis indicated that the AOTAC group had a greater significant change in all of parameters, compared with the AOT and control groups. Conclusion: Our findings suggest that AOTAC may be an effective therapeutic approach to improve gait symmetry and function in patients with stroke. We believe that this effect is attributable to the change of cortical excitability on motor related to cortical areas.

A Review of Neurofeedback Studies (뉴로피드백의 최신 연구 동향)

  • Lee, Hyuk-Jae;Park, Young-Bae;Park, Young-Jae;Oh, Hwan-Sup
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.11 no.2
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    • pp.13-26
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    • 2007
  • Background: Neurofeedback is an electroencephalographic biofeedback technique for training individuals to alter their brain activity via operant conditioning. Also neurofeedback is a form of behavioural training aimed at developing skills for brain activity. Within the past decade, several neurofeedback studies have been published that tend to overcome the methodological shortcomings of earlier studies. This research describes the methodical basis of neurofeedback and reviews the evidence base for its clinical efficacy and effectiveness in attention-deficit hyperactivity disorder (ADHD). Methods: In neurofeedback training, self-regulation of specific aspects of electrical brain activity is acquired by means of immediate feedback and positive reinforcement. In frequency training, activity in different EEG frequency bands has to be decreased or increased. Slow cortical potentials (SCPs) training is focused on the regulation of cortical excitability. Results: Neurofeedback studies revealed training-specific effects on, for example, attention and memory processes and performance improvements in real-life conditions, in healthy subjects as well as in patients. In several studies it was shown that ADHD symptomatology was reduced after frequency training or SCP(Slow cortical potentials) training. Moreover a decrease of impulsivity errors and an increase of the contingent negative variation. Conclusions: This research provides evidence for both positive behavioural and specific neurophysiological effects of neurofeedback training. Also there is growing evidence for neurofeedback as a valuable module in neuropsychiatric disorders. Further, controlled studies are warranted.

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