Clemens Benjamin, Jung Stefanie, Mingoia Gianluca, Weyer David, Domahs Frank, Willmes Klaus
Department of Psychiatry, Psychotherapy and Psychosomatics, Medical School, RWTH Aachen University, Aachen, Germany; Brain Imaging Facility, Interdisciplinary Center for Clinical Research, Medical School, RWTH Aachen University, Aachen, Germany; Neurological Clinic, Section Neuropsychology, Medical School, RWTH Aachen University, Aachen, Germany.
Department of Psychology, Eberhard Karls University, Tübingen, Germany; Knowledge Media Research Center, IWM-KMRC, Tübingen, Germany.
PLoS One. 2014 Apr 23;9(4):e95984. doi: 10.1371/journal.pone.0095984. eCollection 2014.
Although numerous studies examined resting-state networks (RSN) in the human brain, so far little is known about how activity within RSN might be modulated by non-invasive brain stimulation applied over parietal cortex. Investigating changes in RSN in response to parietal cortex stimulation might tell us more about how non-invasive techniques such as transcranial direct current stimulation (tDCS) modulate intrinsic brain activity, and further elaborate our understanding of how the resting brain responds to external stimulation. Here we examined how activity within the canonical RSN changed in response to anodal tDCS applied over the right angular gyrus (AG). We hypothesized that changes in resting-state activity can be induced by a single tDCS session and detected with functional magnetic resonance imaging (fMRI). Significant differences between two fMRI sessions (pre-tDCS and post-tDCS) were found in several RSN, including the cerebellar, medial visual, sensorimotor, right frontoparietal, and executive control RSN as well as the default mode and the task positive network. The present results revealed decreased and increased RSN activity following tDCS. Decreased RSN activity following tDCS was found in bilateral primary and secondary visual areas, and in the right putamen. Increased RSN activity following tDCS was widely distributed across the brain, covering thalamic, frontal, parietal and occipital regions. From these exploratory results we conclude that a single session of anodal tDCS over the right AG is sufficient to induce large-scale changes in resting-state activity. These changes were localized in sensory and cognitive areas, covering regions close to and distant from the stimulation site.
尽管众多研究对人类大脑的静息态网络（RSN）进行了检测，但迄今为止，对于经颅顶叶皮层施加的非侵入性脑刺激如何调节RSN内的活动，我们知之甚少。研究RSN对顶叶皮层刺激的反应变化，可能会让我们更多地了解诸如经颅直流电刺激（tDCS）等非侵入性技术如何调节大脑内在活动，并进一步深化我们对静息大脑如何对外界刺激做出反应的理解。在此，我们研究了标准RSN内的活动如何因在右侧角回（AG）施加阳极tDCS而发生变化。我们假设单次tDCS刺激能够诱发静息态活动的变化，并能通过功能磁共振成像（fMRI）检测到。在几个RSN中发现了两次fMRI扫描（tDCS前和tDCS后）之间的显著差异，包括小脑、内侧视觉、感觉运动、右侧额顶叶和执行控制RSN，以及默认模式网络和任务正性网络。目前的结果显示，tDCS后RSN活动出现了降低和增加的情况。tDCS后RSN活动降低出现在双侧初级和次级视觉区域以及右侧壳核。tDCS后RSN活动增加广泛分布于大脑，覆盖丘脑、额叶、顶叶和枕叶区域。从这些探索性结果中我们得出结论，在右侧AG进行单次阳极tDCS足以诱发静息态活动的大规模变化。这些变化定位在感觉和认知区域，涵盖了靠近和远离刺激部位的区域。
