1 Stephenson School of Biomedical Engineering, University of Oklahoma , Norman, Oklahoma.
2 Laureate Institute for Brain Research , Tulsa, Oklahoma.
Brain Connect. 2017 Nov;7(9):617-626. doi: 10.1089/brain.2017.0514.
Repetitive transcranial magnetic stimulation (rTMS) has been used in experimental protocols to treat mal de debarquement syndrome (MdDS), a neurological condition that represents a maladaptive brain state resulting from entrainment to external oscillating motion. Medical treatments and biomarkers for MdDS remain limited but neuromodulation with rTMS has shown evidence for therapeutic effects. This study took a neuroimaging approach to examine the neuromodulatory effect of rTMS on MdDS. Twenty individuals with MdDS underwent five daily treatments of rTMS over bilateral dorsolateral prefrontal cortex (DLPFC). Participants received 1 Hz over right DLPFC (1200 pulses) followed by 10 Hz over left DLPFC (2000 pulses). Resting state functional magnetic resonance imaging was acquired before and after treatments to determine functional connectivity changes associated with a positive treatment effect. A single-subject-based analysis protocol was developed to capture the degree of resting state functional connectivity (RSFC) between the rTMS target and the entorhinal cortex (EC), an area previously shown to be hypermetabolic in MdDS. Our results showed that rocking motion perception in subjects was modulated by rTMS over the DLPFC. Improvements in symptoms correlated most strongly with a post-rTMS reduction in functional connectivity between the left EC and the precuneus, right inferior parietal lobule, and the contralateral EC, which are part of the posterior default mode network. Positive response to rTMS correlated with higher baseline RSFC between the DLPFC and the EC. Our findings suggest that baseline prefrontal-limbic functional connectivity may serve as a predictor of treatment response to prefrontal stimulation in MdDS and that RSFC may serve as a dynamic biomarker of symptom status.
重复经颅磁刺激（rTMS）已被应用于实验方案中，以治疗晕动病（MdDS），这是一种代表大脑对外源性振荡运动适应不良的神经系统疾病。MdDS 的医学治疗和生物标志物仍然有限，但 rTMS 的神经调节已显示出治疗效果的证据。本研究采用神经影像学方法研究 rTMS 对 MdDS 的神经调节作用。20 名 MdDS 患者接受了 5 天的双侧背外侧前额叶皮质（DLPFC）rTMS 治疗。参与者在右侧 DLPFC 接受 1Hz（1200 个脉冲），然后在左侧 DLPFC 接受 10Hz（2000 个脉冲）。在治疗前后采集静息态功能磁共振成像，以确定与治疗效果呈正相关的功能连接变化。开发了一种基于单个受试者的分析方案，以捕捉 rTMS 靶区与内嗅皮层（EC）之间的静息态功能连接（RSFC）程度，先前的研究表明内嗅皮层在 MdDS 中代谢过度。我们的结果表明，DLPFC 上的 rTMS 可以调节受试者的摇摆运动感知。症状的改善与 rTMS 后左 EC 与后扣带回、右下顶叶和对侧 EC 之间功能连接的减少密切相关，这些区域是后默认模式网络的一部分。rTMS 的阳性反应与 DLPFC 和 EC 之间较高的基线 RSFC 相关。我们的发现表明，基线前额叶-边缘功能连接可能作为前额叶刺激治疗 MdDS 反应的预测因子，RSFC 可能作为症状状态的动态生物标志物。
