Alexander David M, Flynn Gary J, Wong Wilson, Whitford Thomas J, Harris Anthony W F, Galletly Cherrie A, Silverstein Steven M
Laboratory for Perceptual Dynamics, RIKEN Brain Science Institute, Japan.
Clin Neurophysiol. 2009 Sep;120(9):1667-82. doi: 10.1016/j.clinph.2009.06.020. Epub 2009 Jul 30.
Schizophrenia is characterized by a deficit in context processing, with physiological correlates of hypofrontality and reduced amplitude P3b event-related potentials. We hypothesized an additional physiological correlate: differences in the spatio-temporal dynamics of cortical activity along the anterior-posterior axis of the scalp.
This study assessed latency topographies of spatio-temporal waves under task conditions that elicit the P3b. EEG was recorded during separate auditory and visual tasks. Event-related spatio-temporal waves were quantified from scalp EEG of subjects with first episode schizophrenia (FES) and matched controls.
The P3b-related task conditions elicited a peak in spatio-temporal waves in the delta band at a similar latency to the P3b event-related potential. Subjects with FES had fewer episodes of anterior to posterior waves in the 2-4 Hz band compared to controls. Within the FES group, a tendency for fewer episodes of anterior to posterior waves was associated with high Psychomotor Poverty symptom factor scores.
Subjects with FES had altered global EEG dynamics along the anterior-posterior axis during task conditions involving context update.
The directional nature of this finding and its association with Psychomotor Poverty suggest this result is related to findings of hypofrontality in schizophrenia.
精神分裂症的特征在于情境处理缺陷，伴有额叶功能低下和P3b事件相关电位波幅降低的生理相关性。我们假设了另一种生理相关性：沿头皮前后轴的皮质活动时空动力学差异。
本研究评估了在诱发P3b的任务条件下时空波的潜伏期地形图。在单独的听觉和视觉任务期间记录脑电图。从首发精神分裂症（FES）患者和匹配的对照组的头皮脑电图中量化事件相关的时空波。
与P3b事件相关电位潜伏期相似，与P3b相关的任务条件在δ频段的时空波中引发了一个峰值。与对照组相比，FES患者在2-4Hz频段从前向后波的发作次数更少。在FES组中，从前向后波发作次数较少的趋势与高精神运动性贫困症状因子得分相关。
在涉及情境更新的任务条件下，FES患者沿前后轴的全脑脑电图动力学发生了改变。
这一发现的方向性及其与精神运动性贫困的关联表明，该结果与精神分裂症额叶功能低下的发现有关。
