Abstract:
The dorsolateral prefrontal cortex (dlPFC) is implicated in top-down regulation of emotion, but the detailed network mechanisms require further elucidation. To investigate network-level functions of the dlPFC in emotion regulation, this study measured changes in task-based activation, resting-state and task-based functional connectivity (FC) patterns following suppression of dlPFC excitability by 1-Hz repetitive transcranial magnetic stimulation (rTMS). In a sham-controlled within-subject design, 1-Hz active or sham rTMS was applied to the right dlPFC of 19 healthy volunteers during two separate counterbalanced sessions. Following active and sham rTMS, functional magnetic resonance imaging (fMRI) was conducted in the resting state (rs-fMRI) and during approach-avoidance task responses to pictures with positive and negative emotional content (task-based fMRI). Activation and generalized psychophysiological interaction analyses were performed on task-based fMRI, and seed-based FC analysis was applied to rs-fMRI data. Task-based fMRI revealed greater and more lateralized activation in the right hemisphere during negative picture responses compared to positive picture responses. After active rTMS, greater activation was observed in the left middle prefrontal cortex compared to sham rTMS. Further, rTMS reduced response times and error rates in approach to positive pictures compared to negative pictures. Significant FC changes due to rTMS were observed predominantly in the frontoparietal network (FPN) and visual network (VN) during the task, and in the default mode network (DMN) and VN at rest. Suppression of right dlPFC activity by 1-Hz rTMS alters large-scale neural networks and modulates emotion, supporting potential applications for the treatment of mood disorders.
摘要:
背外侧前额叶皮层(dlPFC)与自上而下的情绪调节有关,但是详细的网络机制需要进一步阐明。为了研究dlPFC在情绪调节中的网络级功能,这项研究测量了基于任务的激活的变化,1Hz重复经颅磁刺激(rTMS)抑制dlPFC兴奋性后的静息状态和基于任务的功能连接(FC)模式。在一个假控制的受试者内部设计中,在两个单独的平衡会话中,将1-Hz主动或假rTMS应用于19名健康志愿者的右dlPFC。在主动和假rTMS之后,功能磁共振成像(fMRI)在静息状态(rs-fMRI)下进行,并在回避入路任务时对具有正面和负面情绪内容的图片做出反应(基于任务的fMRI)进行.在基于任务的功能磁共振成像上进行了激活和广义心理生理相互作用分析,并将基于种子的FC分析应用于rs-fMRI数据。基于任务的功能磁共振成像显示,与正面图像响应相比,负面图像响应期间右半球的激活更大,更偏侧。活动rTMS后,与假rTMS相比,在左中前额叶皮质观察到更大的激活.Further,与负面图片相比,rTMS减少了正面图片的响应时间和错误率。在任务期间,主要在额叶顶网络(FPN)和视觉网络(VN)中观察到rTMS引起的显着FC变化,并且在默认模式网络(DMN)和VN中处于静止状态。1HzrTMS抑制右dlPFC活动会改变大规模神经网络并调节情绪,支持治疗情绪障碍的潜在应用。