Penn Image Computing and Science Laboratory (PICSL), Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA.
Hippocampus. 2013 Jan;23(1):1-6. doi: 10.1002/hipo.22051. Epub 2012 Jul 20.
Pathology at preclinical and prodromal stages of Alzheimer's disease (AD) may manifest itself as measurable functional change in neuronal networks earlier than detectable structural change. Functional connectivity as measured using resting-state functional magnetic resonance imaging has emerged as a useful tool for studying disease effects on baseline states of neuronal networks. In this study, we use high resolution MRI to label subregions within the medial temporal lobe (MTL), a site of early pathology in AD, and report an increase in functional connectivity in amnestic mild cognitive impairment between entorhinal cortex and subregions of the MTL, with the strongest effect in the anterior hippocampus. However, our data also replicated the effects of decreased connectivity of the MTL to other nodes of the default mode network reported by other researchers. This dissociation of changes in functional connectivity within the MTL versus the MTL's connection with other neocortical structures can help enrich the characterization of early stages of disease progression in AD.
阿尔茨海默病（AD）的临床前和前驱期病理学可能表现为神经元网络的可测量功能变化，早于可检测的结构变化。使用静息态功能磁共振成像测量的功能连接已成为研究疾病对神经元网络基线状态影响的有用工具。在这项研究中，我们使用高分辨率 MRI 标记内侧颞叶（MTL）内的亚区，AD 的早期病变部位，并报告在遗忘型轻度认知障碍中，内嗅皮层与 MTL 的亚区之间的功能连接增加，在前海马体中作用最强。然而，我们的数据还复制了其他研究人员报告的 MTL 与默认模式网络其他节点的连接性降低的影响。这种 MTL 内功能连接变化与 MTL 与其他新皮层结构连接变化的分离，有助于丰富 AD 疾病进展早期阶段的特征描述。
