Department of Psychiatry & Behavioral Sciences, University of Minnesota, Minneapolis, MN, USA.
Minneapolis Veterans Affairs Health Care System, Minneapolis, MN, USA.
Sci Rep. 2021 Sep 8;11(1):17852. doi: 10.1038/s41598-021-97303-6.
The brain at rest generates cycles of electrical activity that have been shown to be abnormal in people with schizophrenia. The alpha rhythm (~ 10 Hz) is the dominant resting state electrical cycle and each person has a propensity toward a particular frequency of oscillation for this rhythm. This individual alpha peak frequency (IAPF) is hypothesized to be central to visual perceptual processes and may have downstream influences on cognitive functions such as attention, working memory, or problem solving. In the current study we sought to determine whether IAPF was slower in schizophrenia, and whether lower IAPF predicted deficits in visual perception and cognition that are often observed in schizophrenia. Eyes-closed resting state EEG activity, visual attention, and global cognitive functioning were assessed in individuals with schizophrenia (N = 104) and a group of healthy controls (N = 101). Compared to controls, the schizophrenia group showed slower IAPF and was associated with poorer discrimination of visual targets and nontargets on a computerized attention task, as well as impaired global cognition measured using neuropsychological tests across groups. Notably, disruptions in visual attention fully mediated the relationship between IAPF and global cognition across groups. The current findings demonstrate that slower alpha oscillatory cycling accounts for global cognitive deficits in schizophrenia by way of impairments in perceptual discrimination measured during a visual attention task.
静息状态下的大脑会产生电活动循环，研究表明精神分裂症患者的这种电活动循环存在异常。α 节律（~10 Hz）是静息状态下占主导地位的电活动循环，每个人的这种节律都倾向于特定的频率振荡。该节律的个体α峰值频率（IAPF）被假设为视觉感知过程的核心，并且可能对注意力、工作记忆或解决问题等认知功能产生下游影响。在目前的研究中，我们试图确定 IAPF 在精神分裂症中是否较慢，以及较低的 IAPF 是否预测到经常在精神分裂症中观察到的视觉感知和认知缺陷。我们评估了 104 名精神分裂症患者和 101 名健康对照组个体的闭眼静息状态脑电图活动、视觉注意力和整体认知功能。与对照组相比，精神分裂症组的 IAPF 较慢，并且与在计算机化注意力任务中对视觉目标和非目标的辨别能力较差，以及跨组使用神经心理学测试测量的整体认知受损有关。值得注意的是，视觉注意力的中断完全介导了 IAPF 和跨组整体认知之间的关系。目前的研究结果表明，较慢的α振荡循环通过在视觉注意力任务中测量的感知辨别障碍来解释精神分裂症中的整体认知缺陷。
