University Medical Center Hamburg-Eppendorf, Department of Psychiatry and Psychotherapy, Psychiatry Neuroimaging Branch (PNB), Hamburg, Germany.
J Psychiatr Res. 2011 May;45(5):699-705. doi: 10.1016/j.jpsychires.2010.10.002. Epub 2010 Nov 9.
There is growing evidence of abnormalities of high-frequency oscillations in the gamma-range of the electroencephalography in schizophrenia. The generation of neural activity in the gamma-band was shown to be critically related to a glutamatergic and GABAergic microcircuit which is also known to be involved in the pathophysiology of schizophrenia. Recently, a reduction of the early auditory evoked gamma-band response (eGBR) in schizophrenic patients was reported. In order to investigate the possible applicability of this neurophysiological marker as an intermediate phenotype for schizophrenia, this is the main question of our investigation: Is the early eGBR decreased regarding evoked power and phase locking in first-degree relatives of patients with schizophrenia?
We investigated the early eGBR in 17 unaffected first-degree relatives of patients with schizophrenia and in age-, gender- and education-matched groups of schizophrenic patients and healthy controls using an auditory reaction task.
First-degree relatives of patients with schizophrenia and schizophrenic patients showed a significant reduction of evoked power and phase locking of the early eGBR compared to healthy controls.
This study shows significantly reduced evoked power and phase locking of the early auditory eGBR in first-degree relatives of patients with schizophrenia pointing to the applicability of this marker as a heritable intermediate phenotype for schizophrenia. The findings are in line with the hypothesis of a disturbed GABAergic interneural modulation of pyramidal cells in schizophrenia and findings of different schizophrenia risk genes associated with transmission at glutamatergic and GABAergic synapses.
越来越多的证据表明精神分裂症患者脑电图的高频振荡在γ波段存在异常。神经活动在γ频带的产生被证明与谷氨酸能和 GABA 能微电路密切相关，该微电路也被认为与精神分裂症的病理生理学有关。最近，有报道称精神分裂症患者的早期听觉诱发γ频带反应（eGBR）减少。为了研究这种神经生理标志物作为精神分裂症中间表型的可能适用性，这是我们研究的主要问题：精神分裂症患者的一级亲属的早期 eGBR 在诱发功率和相位锁定方面是否减少？
我们使用听觉反应任务，对 17 名未受影响的精神分裂症患者的一级亲属以及年龄、性别和教育匹配的精神分裂症患者和健康对照组的早期 eGBR 进行了调查。
与健康对照组相比，精神分裂症患者的一级亲属和精神分裂症患者的早期 eGBR 的诱发功率和相位锁定显著降低。
这项研究表明，精神分裂症患者的一级亲属的早期听觉 eGBR 的诱发功率和相位锁定显著降低，表明该标志物作为精神分裂症可遗传中间表型的适用性。这些发现与 GABA 能中间神经元对锥体细胞的神经内调制紊乱的假说以及与谷氨酸能和 GABA 能突触传递相关的不同精神分裂症风险基因的发现一致。
