A combined TMS/fMRI study of intensity-dependent TMS over motor cortex
A combined TMS/fMRI study of intensity-dependent TMS over motor cortex
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DOI：
10.1016/s0006-3223(98)00368-0
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发表时间：
1999-02-15
影响因子：
10.6
通讯作者：
George, MS
中科院分区：
文献类型：
--
作者：
Bohning, DE;Shastri, A;George, MS
背景：经颅磁刺激(TMS)允许使用时变磁场对神经元进行无创刺激。研究人员已经开始将TMS与功能成像相结合，以同时刺激和成像大脑活动。方法：在1.5Tesla(T)磁共振扫描仪上，7名成人在左侧运动皮质上方用8字形TMS线圈刺激拇指，同时连续采集血氧水平依赖(BOLD)平面图像，TMS以1 Hz的频率交替传递，以110%和80%的运动阈值间隔休息时间。结果：尽管TMS线圈产生了一些伪影，并降低了信噪比(SNR)，但TMS在18秒长的序列中以110%和80%的间隔进行TMS。无论是在本地还是远程，高强度TMS引起的激活比低强度TMS引起的更大，TMS引起的血流变化的幅度(约增加3%)和时间起始(2-5秒)似乎与使用其他运动和认知任务所引起的相似，结论：尽管这一潜在的强大方法仍在改进中，联合TMS/fMRI在技术上是可行的，并产生可测量的剂量依赖的脑活动变化。(C)1999年生物精神病学学会。
Background: Transcranial magnetic stimulation (TMS) allows noninvasive stimulation of neurons using time-varying magnetic fields. Researchers have begun combining TMS with functional imaging to simultaneously stimulate and image brain activity. Recently, the feasibility of interleaving TMS with functional magnetic resonance imaging (fMRI) was demonstrated This study tests this new method to determine if TMS at different intensities shows different local and remote activation.Methods: Within a 1.5 Tesla (T) MRI scanner, seven adults were stimulated with a figure-eight TMS coil over the left motor cortex for thumb, while continuously acquiring blood oxygen level dependent (BOLD) echoplanar images, TMS was applied at I Hz in 18-second long trains delivered alternately at 110% and 80% of motor threshold separated by rest periods.Results: Though the TMS coil caused some artifacts and reduced the signal to noise ratio (SNR), higher intensity TMS caused greater activation than lower, both locally and remotely, The magnitude ( approximate to 3% increase) and temporal onset (2 to 5 sec) of TMS induced bloodflow changes appear similar to those induced using other motor and cognitive tasks,Conclusions: Though work remains in refining this potentially powerful method, combined TMS/fMRI is both technically feasible and produces measurable dose-dependent changes in brain activity. (C) 1999 Society of Biological Psychiatry.