Bediou B, Hénaff M-A, Bertrand O, Brunelin J, d'Amato T, Saoud M, Krolak-Salmon P
Service du Professeur Dalery, centre hospitalier Le Vinatier, université Lyon-1, EA 3092, 95, boulevard Pinel, 69677 Bron cedex, France.
Neurophysiol Clin. 2007 Apr-May;37(2):77-87. doi: 10.1016/j.neucli.2007.04.001. Epub 2007 Apr 13.
Abnormal emotion processing in schizophrenia affects social and functional outcome. Spatiotemporal brain mechanisms underlying this deficit are unclear.
Event-related potential (ERP) responses to emotional and neutral face processing during an implicit (gender detection) and an explicit (expression detection) task were compared between a group of healthy volunteers (n=10) and a group of patients with schizophrenia (n=10).
Whereas patients had normal primary visual cortex responses, the early modulation of occipital, temporal, and frontal responses by emotional expression observed in controls was absent in patients. The occipito-temporal N170 amplitude was reduced in patients relative to controls during expression detection, but not during gender detection. Frontal activity within 180-250ms was reduced in patients compared to controls. As opposed to controls, no significant difference was seen in patients at the right temporal electrode (T6) between amplitudes of long-latency ERPs elicited by distinct emotions during the expression detection task.
In patients with schizophrenia, abnormal early extraction of expression-related information in the occipito-temporal cortex (before 170ms) impairs structural encoding of facial expressions (N170) and may disrupt motivation- and task-dependent context processing (180-250ms time window) of expression-related facial features. Moreover, top-down neuromodulation from frontal and limbic structures to visual occipito-temporal cortex may not be sufficient to optimize the extraction of expression-specific face features.
精神分裂症患者异常的情绪加工会影响社交和功能结局。这种缺陷背后的脑时空机制尚不清楚。
比较了一组健康志愿者（n = 10）和一组精神分裂症患者（n = 10）在一项内隐任务（性别检测）和一项外显任务（表情检测）中对情绪和中性面孔加工的事件相关电位（ERP）反应。
虽然患者的初级视觉皮层反应正常，但患者缺乏对照组中观察到的情绪表达对枕叶、颞叶和额叶反应的早期调制。在表情检测期间，患者相对于对照组的枕颞N170波幅降低，但在性别检测期间未降低。与对照组相比，患者在180 - 250ms内的额叶活动减少。与对照组不同，在表情检测任务中，患者右侧颞叶电极（T6）处由不同情绪诱发的长潜伏期ERP波幅之间没有显著差异。
在精神分裂症患者中，枕颞叶皮层（170ms之前）对表情相关信息的早期异常提取损害了面部表情的结构编码（N170），并可能破坏与表情相关面部特征的动机和任务依赖的情境加工（180 - 250ms时间窗）。此外，从额叶和边缘结构到枕颞视觉皮层的自上而下的神经调制可能不足以优化表情特异性面部特征的提取。
