Overview of the demographics.

“Efference copy” and “corollary discharge” mechanisms may help to distinguish internal from external stimuli. Previous studies indicate that patients with schizophrenia show a lack of N1 evoked response potential component amplitude suppression to self-initiated auditory stimuli, suggesting a corollary discharge impairment. In our study, we examined N1 and P2 component amplitude suppression in 27 patients with schizophrenia and 30 healthy controls using an auditory button-press paradigm. In addition to symptom ratings we conducted neuropsychological assessments. Our findings replicated N1 amplitude suppression to self-generated tones in schizophrenia patients. We found no correlation between N1, P2, and lateralized readiness potential, suggesting that the readiness potential may not directly represent corollary discharge mechanisms. Cognition performance was reduced in schizophrenia patients and performance reduction correlated with negative symptoms. Cognition was not associated with evoked potential data. Regarding the P2 component, P2 suppression to self-generated tones was observed in patients as well as in controls. In conclusion, the N1 and the P2 component seem to be differentially involved in corollary discharge and efference copy mechanisms. Further investigation is needed to elucidate functional differences and sources of both components in this context.

传出副本（efference copy）与伴随放电（corollary discharge）机制有助于区分内源性与外源性刺激。既往研究表明，精神分裂症患者对自我发起的听觉刺激的N1诱发电位（evoked response potential）成分振幅未出现抑制现象，提示其伴随放电功能受损。本研究采用听觉按键范式（auditory button-press paradigm），纳入27名精神分裂症患者与30名健康对照者，对其N1及P2成分的振幅抑制情况进行了检测。除症状评定外，本研究还开展了神经心理学评估（neuropsychological assessments）。研究结果重复验证了精神分裂症患者对自发音调的N1振幅抑制效应。本研究未发现N1、P2与偏侧准备电位（lateralized readiness potential）之间存在相关性，提示准备电位或许并非直接对应伴随放电机制。精神分裂症患者的认知表现有所下降，且该表现下降与阴性症状呈显著相关，但认知表现与诱发电位数据并无关联。就P2成分而言，患者组与对照组均观察到了对自发音调的P2抑制效应。综上，N1与P2成分似乎在伴随放电及传出副本机制中发挥了差异化的作用。未来仍需开展进一步研究，以阐明这两种成分在此场景下的功能差异与神经起源。