Center for Functional Brain Imaging, New Mexico VA Health Care System, 1501 San Pedro Drive S.E., Albuquerque, NM 87108, USA.
Am J Psychiatry. 2010 Oct;167(10):1264-75. doi: 10.1176/appi.ajp.2010.09071059. Epub 2010 Jul 15.
Abnormal 50- and 100-msec event-related brain activity derived from paired-click procedures are well established in schizophrenia. There is little agreement on whether group differences in the ratio score, i.e., the ratio of EEG amplitude after the second stimulus (S2) to the amplitude after the first stimulus (S1), reflect an encoding or gating abnormality. In addition, the functional implications remain unclear. In the present study, EEG and magnetoencephalography (MEG) were used to examine paired-click measures and cognitive correlates of paired-click activity.
EEG and whole-cortex MEG data were acquired during the standard paired-click paradigm in 73 comparison subjects and 79 schizophrenia patients. Paired-click ratio scores were obtained at 50 msec (P50 evoked potential at Cz, M50 at left and right superior temporal gyrus [STG]) and 100 msec (N100 at Cz, M100 at left and right STG). A cognitive battery assessing attention, working memory, and long-delay memory was administered. IQ was also estimated.
Groups differed on ratio score and amplitude of S1 response. Ratio scores at 50 msec and 100 msec and S1 amplitude predicted variance in attention (primarily S1 amplitude), working memory, and long-delay memory. The attention findings remained after removal of variance associated with IQ.
Associations between paired-click measures and cognitive performance in patients support 50-msec and 100-msec ratio and amplitude scores as clinically significant biomarkers of schizophrenia. In general, cognitive performance was better predicted by the ability to encode auditory information than the ability to filter redundant information.
从双耳分听程序中得出的异常 50ms 和 100ms 事件相关脑活动在精神分裂症中已得到充分证实。对于比率评分（即第二个刺激（S2）后的脑电振幅与第一个刺激（S1）后的振幅之比）的组间差异是否反映了编码或门控异常，尚未达成共识。此外，其功能意义仍不清楚。在本研究中，我们使用脑电图（EEG）和脑磁图（MEG）来检查双耳分听测量值以及双耳分听活动的认知相关性。
在 73 名对照受试者和 79 名精神分裂症患者中采集标准双耳分听范式下的 EEG 和全皮质 MEG 数据。在 50ms（Cz 处的 P50 诱发电位，左、右颞上回[STG]处的 M50）和 100ms（Cz 处的 N100，左、右 STG 处的 M100）处获得双耳分听比率评分。还进行了一个评估注意力、工作记忆和长时记忆的认知测试。还估计了智商。
两组在比率评分和 S1 反应幅度上存在差异。50ms 和 100ms 的比率评分以及 S1 振幅预测了注意力（主要是 S1 振幅）、工作记忆和长时记忆的方差。在去除与智商相关的方差后，注意力的发现仍然存在。
患者的双耳分听测量值与认知表现之间的关联支持 50ms 和 100ms 比率和振幅评分作为精神分裂症的有临床意义的生物标志物。总的来说，认知表现可以更好地通过对听觉信息的编码能力来预测，而不是通过过滤冗余信息的能力来预测。
