Aeberli Tina, Müller Mario, Theodoridou Anastasia, Hagenmuller Florence, Seifritz Erich, Walitza Susanne, Rössler Wulf, Kawohl Wolfram, Heekeren Karsten
Department of Psychiatry, Psychotherapy and Psychosomatics, University of Zurich, Zurich, Switzerland.
The Zurich Program for Sustainable Development of Mental Health Services (ZInEP), University of Zurich, Zurich, Switzerland.
Front Psychiatry. 2023 Jul 19;14:1130809. doi: 10.3389/fpsyt.2023.1130809. eCollection 2023.
Deficits of mismatch negativity (MMN) in patients with schizophrenia have been demonstrated many times and there is growing evidence that alterations of MMN already exist in individuals at risk for psychosis. The present study examines differences in MMN between subjects fulfilling ultra-high risk (UHR) or only basic symptoms criteria and it addresses the question, if MMN source analysis can improve prediction of transition to psychosis.
The MMN to duration, frequency, and intensity deviants was recorded in 50 healthy controls and 161 individuals at risk for psychosis classified into three subgroups: only basic symptoms ( = 74), only ultra-high risk ( = 13) and persons who fulfill both risk criteria ( = 74). Based on a three-source model of MMN generation, we conducted an MMN source analysis and compared the amplitudes of surface electrodes and sources among the three groups.
Significant differences in MMN generation among the four groups were revealed at surface electrodes Cz and C4 ( < 0.05) and at the frontal source ( < 0.001) for duration deviant stimuli. The 15 subjects from the risk groups who subsequently developed a manifest psychosis had a significantly lower MMN amplitude at frontal source ( = 0.019) without showing significant differences at surface electrodes. Low activity at frontal MMN source increased the risk of transition to manifest disease by the factor 3.12 in UHR subjects.
MMN activity differed significantly between subjects presenting only basic symptoms and subjects which additionally meet UHR criteria. The largest differences between groups as well as between individuals with and without transition were observed at the frontal source. The present results suggest that source analysis is more sensitive than surface electrodes in psychosis risk prediction by MMN.
精神分裂症患者的失匹配负波（MMN）缺陷已被多次证实，且越来越多的证据表明，处于精神病风险的个体中已经存在MMN改变。本研究考察了符合超高风险（UHR）或仅符合基本症状标准的受试者之间MMN的差异，并探讨了MMN源分析是否能改善向精神病转变的预测。
记录了50名健康对照者和161名处于精神病风险的个体对持续时间、频率和强度偏差刺激的MMN，这些个体被分为三个亚组：仅基本症状组（n = 74）、仅超高风险组（n = 13）和同时符合两种风险标准的个体（n = 74）。基于MMN产生的三源模型，我们进行了MMN源分析，并比较了三组之间表面电极和源的振幅。
在表面电极Cz和C4（p < 0.05）以及额叶源（p < 0.001）处，四组之间在持续时间偏差刺激的MMN产生上存在显著差异。随后发展为明显精神病的风险组中的15名受试者在额叶源处的MMN振幅显著较低（p = 0.019），而在表面电极处未显示出显著差异。额叶MMN源的低活动使UHR受试者向明显疾病转变的风险增加了3.12倍。
仅表现出基本症状的受试者与另外符合UHR标准的受试者之间的MMN活动存在显著差异。在额叶源处观察到组间以及有或无转变的个体之间的最大差异。目前的结果表明，在通过MMN进行精神病风险预测中，源分析比表面电极更敏感。
