Department of Diagnostic Radiology, Yale University School of Medicine, The Anlyan Center, 300 Cedar Street, New Haven, CT 06520-8042, USA.
Neuroimage. 2010 Jan 1;49(1):823-34. doi: 10.1016/j.neuroimage.2009.07.028. Epub 2009 Jul 22.
This work examines the influence of changes in baseline activity on the intrinsic functional connectivity fMRI (fc-fMRI) in humans. Baseline brain activity was altered by inducing anesthesia (sevoflurane end-tidal concentration 1%) in human volunteers and fc-fMRI maps between the pre-anesthetized and anesthetized conditions were compared across different brain networks. We particularly focused on low-level sensory areas (primary somatosensory, visual, and auditory cortices), the thalamus, and pain (insula), memory (hippocampus) circuits, and the default mode network (DMN), the latter three to examine higher-order brain regions. The results indicate that, while fc-fMRI patterns did not significantly differ (p<0.005; 20-voxel cluster threshold) in sensory cortex and in the DMN between the pre- and anesthetized conditions, fc-fMRI in high-order cognitive regions (i.e. memory and pain circuits) was significantly altered by anesthesia. These findings provide further evidence that fc-fMRI reflects intrinsic brain properties, while also demonstrating that 0.5 MAC sevoflurane anesthesia preferentially modulates higher-order connections.
这项工作研究了基线活动变化对人类功能连接磁共振成像 (fc-fMRI) 的影响。通过在人类志愿者中诱导麻醉（七氟醚呼气末浓度 1%）来改变基线脑活动，并比较了麻醉前和麻醉条件下不同脑网络之间的 fc-fMRI 图谱。我们特别关注低水平感觉区域（初级感觉、视觉和听觉皮层）、丘脑和疼痛（脑岛）、记忆（海马）回路以及默认模式网络（DMN），后三个区域用于检查高级脑区。结果表明，虽然在麻醉前和麻醉条件下，感觉皮层和 DMN 之间的 fc-fMRI 模式没有显著差异（p<0.005；20 个体素簇阈值），但麻醉对高级认知区域（即记忆和疼痛回路）的 fc-fMRI 有显著影响。这些发现进一步证明了 fc-fMRI 反映了内在的大脑特性，同时也表明 0.5 MAC 七氟醚麻醉优先调节高级连接。
