精神分裂症情绪刺激加工异常的P300成分研究

Abnormal P300 activities during emotional stimuli processing in patients with schizophrenia

目的分析精神分裂症(schizophrenia,SZ)患者加工情绪性图片刺激时P300成分的特征,比较症状严重程度不同SZ患者的差异。方法收集2019年10月至2020年10月上海市精神卫生中心住院的SZ患者40例,其中精神分裂症患者重度症状(severe schizophrenia,SZ-S)组20例,轻度症状(mild schizophrenia,SZ-M)组20例,于社区招募健康对照(healthy control,HC)20名。采用阳性与阴性症状量表(positive and negative syndrome scale,PANSS)评估精神分裂症患者的临床症状;采用情绪图片(负性、正性)任务诱发脑电数据,比较P3b(靶刺激诱发)、P3a(情绪图片诱发)成分波幅和潜伏期。结果对于P3b成分的比较显示:在负性情绪图片任务下,波幅的组别效应有统计学意义(F=3.559,P=0.036),SZ-S组P3b平均波幅值(8.61±1.06)μV小于HC组(12.47±0.98)μV,差异有统计学意义(P=0.031),SZ-M组(10.60±1.10)μV和SZ-S组、HC组无统计学差异(P>0.05);在正性情绪图片任务下,P3b波幅和潜伏期组间无统计学差异(P>0.05)。P3a成分的波幅存在组间差异(F=6.784,P=0.002),SZ-S组(3.80±0.90)μV和SZ-M组(2.66±0.83)μV的P3a幅值小于HC组(6.83±0.83)μV,差异有统计学意义(P<0.05),SZ-S组和SZ-M组无统计学差异(P>0.05)。结论SZ-S组和SZ-M组均存在对情绪刺激自动注意资源分配的损伤,SZ-S组的P3b成分幅值降低,提示对负性情绪刺激的主动加工过程受损。

Objective The present study aimed to explore the mechanism of abnormal emotional processing in schizophrenia(SZ)reflected by the P300 component,a typical event-related potential(ERP)component.In addition,we explore whether the emotional processing deficits were associated with the severity of clinical symptoms.Methods Twenty SZ patients with severe symptoms(SZ-S)and 20 SZ patients with mild symptoms(SZ-M)were recruited from inpatients in Shanghai Mental Health Center,from October 2019 to October 2020.Twenty healthy controls(HC)were recruited in the community.All patients were assessed by Positive and Negative Syndrome Scale(PANSS).EEG data were obtained from all participants when they were performing an P300 oddball paradigm with emotional pictures as novel stimuli.P3b evoked by target stimuli and P3a evoked by novel stimuli were identified.P3b and P3a amplitudes were compared by repeated measure ANOVA with group(SZ-S,SZ-M,HC)as a between-group factor and emtoin(negative,positive)as a within group factor.Results Under negative emotional condition,P3b amplitudes in SZ-S(8.61±1.06)μV were significantly lower than those in HC(12.47±0.98)μV,while P3b amplitudes in SZ-M(10.60±1.10)μV were comparable with SZ-S and HC.P3b latency showed no significant differences among three groups.Under positive emotional condition,there was no significant difference of P3 bamplitude and latencyamong three groups.BothSZ-S(3.80±0.90)μV andSZ-M(2.66±0.83)μV had significantly lower P3a amplitudes than HC(6.83±0.83)μV.Conclusion There is an impaired automatic allocation of attentional resources in both SZ-S and SZ-M patients.The reduction of P3b amplitude suggests the impaired processing of negative stimuli in SZ patients with severe symptoms.