• 제목/요약/키워드: excitability

검색결과 171건 처리시간 0.026초

경두개 직류전류 자극이 대뇌피질의 뇌 활성도에 미치는 영향 (Cortical Activation in the Human Brain induced by Transcranial Direct Current Stimulation)

  • 권용현;김중선;장성호
    • The Journal of Korean Physical Therapy
    • /
    • 제21권4호
    • /
    • pp.73-79
    • /
    • 2009
  • Purpose: Recently, neurostimulation studies involving manipulation of cortical excitability of the human brain have been increasingly attempted. We investigated whether transcranial direct current stimulation (tDCS) applied to the underlying cerebral cortex, directly induces cortical activation during fMRI scanning. Methods: We recently recruited five healthy subjects without a neurological or psychiatric history and who were right-handed, as verified by the modified Edinburg Handedness Inventory. fMRI was done while constant anodal tDCS was delivered to the underlying SM1 area?? immediately after the pre-stimulation for eighteen minutes. Results: Group analysis yielded an averaged map that showed that the SM1 area and the superior parietal cortex in the ipsilateral hemisphere were activated. The voxel size and peak intensity were, respectively, 82 and 5.22 in the SM1, and 85 and 5.77 in the superior parietal cortex. Conclusion: Cortical activation can be induced by constant anodal tDCS of the underlying motor cortex. This suggests that tDCS may be an effective therapeutic device for enhancing? physical motor function by modulating neural excitability of the motor cortex.

  • PDF

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

  • Kim, Myoung-Kwon
    • Journal of Magnetics
    • /
    • 제19권2호
    • /
    • pp.170-173
    • /
    • 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.

Role of microglial activation on neuronal excitability in rat substantia gelatinosa

  • Park, Areum;Chun, Sang Woo
    • International Journal of Oral Biology
    • /
    • 제45권4호
    • /
    • pp.225-231
    • /
    • 2020
  • Glial cells, including astrocytes and microglia, interact closely with neurons and modulate pain transmission, particularly under pathological conditions. In this study, we examined the excitability of substantia gelatinosa (SG) neurons of the spinal dorsal horn using a patch clamp recording to investigate the roles of microglial activation in the nociceptive processes of rats. We used xanthine/xanthine oxidase (X/XO), a generator of superoxide anion (O2·-), to induce a pathological pain condition. X/XO treatment induced an inward current and membrane depolarization. The inward current was significantly inhibited by minocycline, a microglial inhibitor, and fluorocitrate, an astrocyte inhibitor. To examine whether toll-like receptor 4 (TLR4) in microglia was involved in the inward current, we used lipopolysaccharide (LPS), a highly specific TLR4 agonist. The LPS induced inward current, which was decreased by pretreatment with Tak-242, a TLR4-specific inhibitor, and phenyl N-t-butylnitrone, a reactive oxygen species scavenger. The X/XO-induced inward current was also inhibited by pretreatment with Tak-242. These results indicate that the X/XO-induced inward current of SG neurons occurs through activation of TLR4 in microglial cells, suggesting that neuroglial cells modulate the nociceptive process through central sensitization.

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

  • 박지원;김종만;김연희
    • 한국전문물리치료학회지
    • /
    • 제10권3호
    • /
    • pp.17-27
    • /
    • 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.

  • PDF

근막이완기법에 의한 유연성 및 혈장 카테콜라민의 변화 (Changes of Flexibility and Plasma Catecholamine by Myofascial Release Approach)

  • 김종순;문동철;장경수
    • 한국콘텐츠학회논문지
    • /
    • 제12권3호
    • /
    • pp.214-221
    • /
    • 2012
  • 최근 일부 연구자에 의해 근막의 자율신경지배가 보고되고 있다. 그러나 근막이완술의 효과에 대한 신경 생리학적 설명과 근거는 없는 실정이다. 이에 본 연구의 목적은 근막이완술에 의해 자율신경계의 흥분이 변화될 수 있는지의 여부를 알아보고자 하였다. 본 연구에서는 건강한 20대 피검자 30명을 15명씩 무작위로 근막이완술군(MG)과 위약대조군(PCG)로 배치하였다. 근막이완술군으로 배정된 피검자들에게는 치료대에 바로 누운 자세에서 두개 기저부 이완기법(cranial base release)을 5분간 적용하였고 위약대조군으로 배정된 피검자들은 같은 자세와 절차를 거치지만 실제 근막이완술을 적용하지 않는 위약 치료를 적용하였다. 근육의 유연성은 경부의 관절가동범위로 측정하였으며 자율신경계의 변화는 심박수, 혈압 그리고 에피네프린과 노르에피네프린의 수치로 측정하였다. 본 연구의 결과는 다음과 같다. 1. 근막이완술군에서 신전과 측방굴곡의 가동범위 변화율이 유의하게 증가하였다. 2. 심박수와 혈압, 그리고 에피네프린의 변화율은 두 군간 유의한 차이가 없었다. 3. 노르에피네프린의 변화율은 두 군간 유의한 차이가 있었다. 본 연구의 결과 근막이완술이 자율신경계의 흥분을 변화 시킬 수 있다는 근거는 없었다.

진동자극 방식이 뇌병변 환자의 상지경직에 미치는 영향 (Effects of Vibration Stimulation Method on Upper Limbs Spasticity in Patients with Brain Lesion)

  • 배세현;김경윤
    • 한국산학기술학회논문지
    • /
    • 제12권7호
    • /
    • pp.3109-3116
    • /
    • 2011
  • 본 연구는 뇌병변으로 상지경직이 관찰되는 환자를 대상으로 자극방식에 따른 진동자극이 경직에 미치는 영향에 대하여 알아보고자 하였다. 뇌병변으로 인해 상지경직이 있는 21명의 환자가 연구에 참여하였고, 실험군 I: 길항근(상완삼두근)자극, 실험군II: 주동근(상완이두근)자극, 실험군III: 동시(상완삼두근 및 상완이두근)자극에 각 7명씩을 배정하여 진동자극을 실시하였다. 척수운동신경원 흥분성을 알아보기 위해 Neuro-EMG_Micro를 이용한 F파를 자극전, 자극 직후, 자극 10분 후, 자극 20분 후에 측정하였고, 임상적 평가로는 MAS(Modified Ashworth Scale)와 MFT(Manual Function Test)를 자극 전, 자극 20분 후에 평가하였다. 본 연구의 결과, MAS는 세군 모두 유의한 감소를 나타냈고, F파 진폭 및 F/M비에서는 세군 모두에서 자극 직후에서부터 유의한 감소를 나타냈으며, 실험군III에서 시간 경과상 변화량이 가장 크게 나타났다. MFT에서는 실험군II와 III에서 유의한 증가를 나타냈으며 특히, 실험군III에서 기능적 변화량이 가장 크게 나타났다. 이러한 결과는 경직근에 대한 진동자극시 경직 주동근이나 길항근에 대한 단일 자극 방식보다는 동시자극 방식이 척수운동신경원의 흥분성 감소 및 상지 운동 기능 향상에 더 효과적임을 확인할 수 있었다.

안면신경마비와 마비성 사시를 병발한 환자의 증례보고 (A Casuistics of a Patient with Facial Palsy and Paralytic Strabismus)

  • 조재훈;김윤범;채병윤
    • 한방안이비인후피부과학회지
    • /
    • 제13권2호
    • /
    • pp.152-164
    • /
    • 2000
  • 1. We experienced one case with facial palsy and paralytic strabismus, which improved under the treatment of Acupuncture, Infrared, Electroacupuncture and Massage. 2. The prognostic factor of facial palsy was affected by On Set and neurodegeneration (such as synkinesis, contraction, spasm and crocodile tear). 3. In facial palsy, Myoneural Excitability Test by Electroacupuncture, which will need the objective clinical standard, was available for the evaluation of therapeutic effect and prognosis.

  • PDF

Modulation of Cloned T-type Calcium Channels

  • Jeong, Seong-Woo
    • 한국생물물리학회:학술대회논문집
    • /
    • 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
    • /
    • pp.20-21
    • /
    • 2002
  • The inflow of Ca$\^$2+/ through voltage-activated T-type calcium channels (T-channels) regulates a variety of cellular functions including neuronal excitability, cardiac pacemaker activity, hormone secretion, smooth muscle contraction, and fertilization. Not only are T-channels enormously important for the normal operation of cells, they also playa critical role in pathophysiological conditions such as cardiac hypertrophy and absence epilepsy.(omitted)

  • PDF

Synaptic Facilitation of Naive and Depressed Synapses in Aplysia

  • Chang, Deok-Jin;Kaang, Bong-Kiun
    • 한국생물물리학회:학술대회논문집
    • /
    • 한국생물물리학회 2001년도 학술 발표회 진행표 및 논문초록
    • /
    • pp.23-23
    • /
    • 2001
  • To evaluate the contribution of cAMP/PKA signal pathway in short-term facilitation, we overexpressed Ap oal receptor in sensory neurons that do not normally express this receptor. We have previously shown that activation of this receptor in sensory cells, by a brief treatment with octopamine (OA), produced short-term facilitation such as membrane depolarization, increase in membrane excitability, spike broadening, and enhanced neurotransmitter release in non-depressed synapse.(omitted)

  • PDF

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

  • Lee, Juyoun;Lee, Ae Young
    • Annals of Clinical Neurophysiology
    • /
    • 제23권1호
    • /
    • pp.7-16
    • /
    • 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.