Role of aberrant neural oscillations for multisensory processing deficits in schizophrenia

神经振荡所反映的兴奋和抑制状态的周期性波动对皮层网络的信息处理至关重要。功能失调的神经连通性与异常振荡有关，可能有助于精神分裂症（ScZ）的病理生理。研究ScZ的神经振荡主要使用感觉刺激方案。最近的行为和神经影像学研究也表明ScZ存在多感觉加工缺陷，但这些缺陷背后的神经生理机制尚不清楚。多感官刺激的整合需要多感官间的信息加工，神经振荡在其中起着重要作用。基于这些原因，多感觉范式有望用于研究ScZ患者的神经振荡。本研究的中心目标是验证异常神经振荡导致ScZ多感觉加工缺陷的假设。该项目包括使用多感觉范式的四项脑电图研究，这些研究先前已在健康参与者中建立了神经振荡的影响。为了揭示ScZ多感觉加工的更全面的图景，实验的特点是广泛的研究问题。实验1将探讨运动一致性如何影响视觉刺激的加工，这反映在感觉皮层的伽马波段振荡（GBO bbb - 30 Hz）中。实验2将考察在嘈杂声学条件下的视听语音处理，表现为颞上沟的β波段振荡（13-30 Hz）。实验3将研究在theta波段振荡（4-7 Hz）和GBO中观察到的由视听语音产生的跨模态预测误差的处理。实验4将研究自上而下注意对基本视听刺激诱发的早期GBO的影响。最先进的分析方法将应用于检查多感觉处理，反映在ScZ患者和健康对照参与者的局部功率、动态网络模式和功能连接中。实验将揭示这些指标的异常是否与ScZ病理生理有关。综上所述，该项目将极大地推进我们对异常神经振荡如何导致精神分裂症多感觉处理缺陷的理解。

Periodic fluctuations of excitatory and inhibitory states, as reflected in neural oscillations, are crucial for information processing in cortical networks. Dysfunctional neural connectivity, which has been linked to abnormal oscillations, presumably contributes to the pathophysiology in schizophrenia (ScZ). Studies examining neural oscillations in ScZ have primarily used unisensory stimulation protocols. Recent behavioral and neuroimaging studies have also suggested multisensory processing deficits in ScZ, but the neurophysiologic mechanisms underlying these deficits are not well understood. The integration of multisensory stimuli requires information processing across multiple senses and neural oscillations play an important role therein. For these reasons, multisensory paradigms are promising for studying neural oscillations in ScZ patients. The central goal of this proposal is to test the assumption that abnormal neural oscillations contribute to multisensory processing deficits in ScZ. The project comprises of four electroencephalography studies using multisensory paradigms for which effects in neural oscillations have been previously established in healthy participants. To reveal a more global picture of multisensory processing in ScZ, the experiments feature a wide range of research questions. Experiment 1 will address how motion congruence affects the processing of visuotactile stimuli, as reflected in gamma-band oscillations (GBO > 30 Hz) in sensory cortices. Experiment 2 will examine audiovisual speech processing under noisy acoustic conditions, as expressed in beta-band oscillations (13-30 Hz) in the superior temporal sulcus. Experiment 3 will investigate the processing of crossmodal prediction errors generated by audiovisual speech, as observed in theta-band oscillations (4-7 Hz) and GBO. Experiment 4 will focus on the influence of top-down attention on early evoked GBO to basic audiovisual stimuli. State-of-the-art analysis approaches will be applied to examine multisensory processing, as reflected in local power, dynamic network patterns, and functional connectivity in ScZ patients and healthy control participants. The experiments will uncover whether abnormalities in these measures relate to the ScZ pathophysiology. Taken together, the project will substantially advance our understanding of how aberrant neural oscillations contribute to multisensory processing deficits in schizophrenia.