Department of Neurology, Medical University of Graz, Graz, Austria.
Neurobiol Aging. 2012 Jan;33(1):197.e1-9. doi: 10.1016/j.neurobiolaging.2010.06.005. Epub 2010 Aug 17.
Severe white matter hyperintensities (WMH) represent cerebral small vessel disease and predict functional decline in the elderly. We used fMRI to test if severe WMH impact on functional brain network organization even before clinical dysfunction. Thirty healthy right-handed/footed subjects (mean age, 67.8 ± 7.5 years) underwent clinical testing, structural MRI and fMRI at 3.0T involving repetitive right ankle and finger movements. Data were compared between individuals with absent or punctuate (n = 17) and early confluent or confluent (n = 13) WMH. Both groups did not differ in mobility or cognition data. On fMRI, subjects with severe WMH demonstrated excess activation in the pre-supplementary motor area (SMA), frontal, and occipital regions. Activation differences were noted with ankle movements only. Pre-SMA activation correlated with frontal WMH load for ankle but not finger movements. With simple ankle movements and no behavioral deficits, elderly subjects with severe WMH demonstrated pre-SMA activation, usually noted with complex tasks, as a function of frontal WMH load. This suggests compensatory activation related to disturbance of frontosubcortical circuits.
严重的脑白质高信号（WMH）代表脑小血管疾病，并可预测老年人的功能下降。我们使用 fMRI 来测试严重的 WMH 是否会影响大脑功能网络的组织，即使在临床功能障碍之前也是如此。30 名健康的右利手/足者（平均年龄 67.8±7.5 岁）接受了临床测试、结构 MRI 和 3.0T 的 fMRI 检查，包括重复的右踝和手指运动。将无或点状（n=17）和早期融合或融合性（n=13）WMH 的个体数据进行比较。两组在运动或认知数据上无差异。在 fMRI 上，严重 WMH 患者的辅助运动前区（SMA）、额叶和枕叶区域存在过度激活。仅在踝部运动时才观察到激活差异。SMA 前区的激活与额叶 WMH 负荷呈正相关，但与手指运动无关。在进行简单的踝部运动且无行为缺陷的情况下，严重 WMH 的老年患者表现出 SMA 前区的激活，这通常与复杂任务有关，是额叶 WMH 负荷的一种功能表现。这表明与额叶下皮质回路紊乱相关的代偿性激活。
