Advanced Computing and Data Science, Cyberinfrastructure and Technology Integration, Clemson University, Clemson, South Carolina, USA.
Department of Speech, Language and Hearing Sciences, Indiana University, Bloomington, Indiana, USA.
Brain Connect. 2021 Sep;11(7):543-552. doi: 10.1089/brain.2020.0901. Epub 2021 May 13.
Stroke can induce large-scale functional reorganization of the brain; however, the spatial patterns of this reorganization remain largely unknown. Using a large ( = 116) sample of participants who were in the chronic stages of stroke, we present a systematic study of the association between brain damage and functional connectivity (FC) within the intact hemisphere. We computed correlations between regional cortical damage and contralateral FC. We identified left-hemisphere regions that had the most pronounced effect on the right-hemisphere FC, and, conversely, right-hemisphere connections where the effect of damage was particularly strong. Notably, the vast majority of significant correlations were positive: damage was associated with an increase in regional contralateral connectivity. These findings lend evidence of the reorganization of contralateral cortical networks as a response to brain damage, which is more pronounced in a set of well-connected regions where connectivity increases with the amount of damage. Impact statement The relatively large sample size combined with our best-of-breed analysis methods provides us with sufficient statistical power and spatial sensitivity to identify a set of brain regions where damage has the strongest impact on contralateral networks, and a set of contralateral functional connections that increase in strength in response to brain damage. Our results demonstrate that the brain's ability to reorganize itself after extensive damage is not distributed equally in space, but is more likely to occur in specific core regions. We believe that the associations between brain damage and increased connectivity in the "intact" hemisphere provide novel, and important, insight into the plasticity of the adult brain.
中风可引起大脑大范围的功能重组，但这种重组的空间模式仍知之甚少。我们使用了一个包含 116 名处于中风慢性期的参与者的大样本，对大脑损伤与完整半球内功能连接（FC）之间的关联进行了系统研究。我们计算了皮质区域损伤与对侧 FC 之间的相关性。我们确定了对右半球 FC 影响最显著的左半球区域，以及损伤影响特别强烈的右半球连接。值得注意的是，绝大多数显著相关性呈正相关：损伤与区域对侧连接的增加有关。这些发现为大脑损伤后对侧皮质网络重组提供了证据，在一组连通性较好的区域中，随着损伤程度的增加，连通性也随之增加，这种重组更为明显。影响说明我们较大的样本量与我们最佳的分析方法相结合，为我们提供了足够的统计能力和空间灵敏度，以识别出一组大脑区域，在这些区域中，损伤对侧网络的影响最大，以及一组对侧功能连接在响应大脑损伤时的强度增加。我们的研究结果表明，大脑在广泛损伤后自我重组的能力在空间上分布不均，而更可能发生在特定的核心区域。我们认为，“完整”半球中大脑损伤与连接增加之间的关联为成年人大脑的可塑性提供了新的、重要的见解。
