Alhourani Ahmad, Wozny Thomas A, Krishnaswamy Deepa, Pathak Sudhir, Walls Shawn A, Ghuman Avniel S, Krieger Donald N, Okonkwo David O, Richardson R Mark, Niranjan Ajay
Department of Neurological Surgery, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
J Neurophysiol. 2016 Oct 1;116(4):1840-1847. doi: 10.1152/jn.00513.2016. Epub 2016 Jul 27.
Mild traumatic brain injury (mTBI) leads to long-term cognitive sequelae in a significant portion of patients. Disruption of normal neural communication across functional brain networks may explain the deficits in memory and attention observed after mTBI. In this study, we used magnetoencephalography (MEG) to examine functional connectivity during a resting state in a group of mTBI subjects (n = 9) compared with age-matched control subjects (n = 15). We adopted a data-driven, exploratory analysis in source space using phase locking value across different frequency bands. We observed a significant reduction in functional connectivity in band-specific networks in mTBI compared with control subjects. These networks spanned multiple cortical regions involved in the default mode network (DMN). The DMN is thought to subserve memory and attention during periods when an individual is not engaged in a specific task, and its disruption may lead to cognitive deficits after mTBI. We further applied graph theoretical analysis on the functional connectivity matrices. Our data suggest reduced local efficiency in different brain regions in mTBI patients. In conclusion, MEG can be a potential tool to investigate and detect network alterations in patients with mTBI. The value of MEG to reveal potential neurophysiological biomarkers for mTBI patients warrants further exploration.
轻度创伤性脑损伤（mTBI）会导致相当一部分患者出现长期认知后遗症。跨功能性脑网络的正常神经通讯中断可能解释了mTBI后观察到的记忆和注意力缺陷。在本研究中，我们使用脑磁图（MEG）检查了一组mTBI受试者（n = 9）与年龄匹配的对照受试者（n = 15）在静息状态下的功能连接性。我们在源空间采用了一种数据驱动的探索性分析，使用不同频段的锁相值。与对照受试者相比，我们观察到mTBI患者特定频段网络中的功能连接性显著降低。这些网络跨越了默认模式网络（DMN）中涉及的多个皮质区域。DMN被认为在个体未从事特定任务时负责记忆和注意力，其破坏可能导致mTBI后的认知缺陷。我们进一步对功能连接矩阵应用了图论分析。我们的数据表明mTBI患者不同脑区的局部效率降低。总之，MEG可以成为研究和检测mTBI患者网络改变的潜在工具。MEG揭示mTBI患者潜在神经生理生物标志物的价值值得进一步探索。
