Department of Diagnostic Imaging, The Hospital for Sick Children, Canada; Rotman Research Institute, Baycrest Health Sciences Centre, Toronto, Canada; Canadian Partnership for Stroke Recovery, Ottawa, Canada.
Department of Diagnostic Imaging, The Hospital for Sick Children, Canada; Neurosciences and Mental Health, SickKids Research Institute, Toronto, Canada.
Neurosci Lett. 2019 Apr 23;699:64-70. doi: 10.1016/j.neulet.2019.01.053. Epub 2019 Jan 31.
Recent evidence suggests that good neurological outcome in subarachnoid hemorrhage (SAH) does not equate to good neuropsychological and cognitive outcome. These individuals continue to face cognitive difficulties in tasks involving mental flexibility, short-term memory and attention, resulting in decreased independence in daily living and reduced ability to return to work. In the current study, we examined the functional connectivity profiles using magnetoencephalography (MEG) in SAH patients, versus controls, during a visual short-term memory, 1-back, task. Our results found that a global measure of MEG-based phase synchrony in the beta band (15-30 Hz), derived from a time window during correct recognition, significantly differentiated the controls from the patients. During correct recognition, the connectivity patterns in the controls were characterized by inter-hemispheric parieto-frontal connections, involving the posterior parietal cortex, while patients appeared to recruit an entirely different network of regions, involving the anterior frontal and temporal regions. Reduced beta-band synchrony during recognition was associated with overall poorer performance, demonstrated as lower accuracy and slower reaction times in patients, but not in controls. This differentiation between groups suggests an important and distinct role of beta-band phase synchronization, perhaps for memory retrieval, associated with good performance. Performance slowing, short-term memory and attention deficits in these patients may be attributed to the impaired beta-band connectivity among prefrontal regions and the posterior parietal cortex.
最近的证据表明，蛛网膜下腔出血（SAH）患者的神经预后良好并不等同于神经心理学和认知预后良好。这些患者在涉及心理灵活性、短期记忆和注意力的任务中仍然面临认知困难，导致日常生活的独立性降低，重返工作的能力下降。在当前的研究中，我们使用脑磁图（MEG）检查了 SAH 患者与对照组在视觉短期记忆、1 回任务中的功能连接谱。我们的研究结果发现，从正确识别期间的时间窗口得出的基于 MEG 的β频带（15-30Hz）相位同步的全局度量可以显著区分对照组和患者。在正确识别期间，对照组的连接模式表现为涉及顶叶皮层的半球间顶-额连接，而患者则似乎募集了一个完全不同的区域网络，涉及额前和颞区。识别过程中β频带同步性降低与患者整体表现较差相关，表现为准确性较低和反应时间较慢，但对照组患者则没有。这种组间差异表明β频带相位同步具有重要且独特的作用，可能与良好的表现相关。这些患者的表现减速、短期记忆和注意力缺陷可能归因于额前区域和顶叶后皮质之间的β频带连接受损。
