Psychosis Clinical Academic Group, Institute of Psychiatry, King's College London, London, UK.
Neuroimage. 2011 Mar 1;55(1):320-8. doi: 10.1016/j.neuroimage.2010.11.075. Epub 2010 Dec 1.
Psychotic disorders are characterized by gray matter and volumetric and electrophysiological abnormalities. The relationship between these factors in the onset of psychotic illness is unclear.
Eighty English-native right-handed subjects (39 subjects at ultra high risk for psychosis "ARMS" and 41 healthy volunteers) were scanned with MRI, and studied using EEG during an oddball task. Both assessments were performed at first clinical presentation. The ARMS subjects were then followed clinically, with the MRI and EEG assessments repeated in a subgroup of each sample.
The P300 amplitude at presentation was significantly lower in the ARMS subjects than in controls. At baseline, the ARMS group showed reduced gray matter volume relative to controls in the right superior frontal gyrus, left medial frontal gyrus, left inferior frontal gyrus, right orbital gyrus and right supramarginal gyrus. Transition to psychosis (26%) was associated with reduced gray matter in the right inferior parietal lobule and in the left parahippocampal gyrus. Within the ARMS group, there was a positive correlation between P300 amplitude and gray matter volume in the right supramarginal gyrus. A significant group by P300 by gray matter interaction was detected in the left medial frontal gyrus. Longitudinal assessment revealed progressive gray matter alterations in prefrontal and subcortical areas of the ARMS but no significant changes in P300 amplitude over time.
P300 abnormalities in the ARMS are related to alterations in regional gray matter volume and represent a correlate of an increased vulnerability to psychosis.
精神障碍的特征是灰质、体积和电生理异常。这些因素与精神病发病之间的关系尚不清楚。
对 80 名英语为母语的右利手受试者（39 名处于精神病超高风险期的受试者“ARMS”和 41 名健康志愿者）进行 MRI 扫描，并在一项Oddball 任务中进行 EEG 研究。这些评估都是在首次临床就诊时进行的。然后对 ARMS 受试者进行临床随访，对每个样本的亚组重复进行 MRI 和 EEG 评估。
ARMS 受试者在出现时的 P300 振幅明显低于对照组。在基线时，与对照组相比，ARMS 组在右侧额上回、左侧额内侧回、左侧额下回、右侧眶回和右侧缘上回的灰质体积减少。向精神病的转变（26%）与右侧下顶叶和左侧海马旁回的灰质减少有关。在 ARMS 组内，P300 振幅与右侧缘上回的灰质体积呈正相关。在左侧额内侧回检测到 P300 振幅与灰质的显著组间交互作用。纵向评估显示 ARMS 患者的前额叶和皮质下区域的灰质逐渐改变，但 P300 振幅随时间没有显著变化。
ARMS 中的 P300 异常与区域灰质体积的改变有关，是精神病易感性增加的相关指标。
