Cold Pressor Task中威胁性图片信息相关事件电位研究

The ERPs of Threating Information on Cold Pressor Task

目的：本研究选用冷压疼痛诱导范式（Cold Pressor Task,CPT）作为诱发疼痛的手段,探讨疼痛条件下,威胁性信息的ERPs反应。方法：采用组内设计,在CPT中给被试提供威胁型（冻伤和无关威胁）和中性图片。结果：冻伤威胁性信息与无关威胁信息和非威胁信息之间在CPT疼痛的相关事件电位存在显著差异。重复测量方差分析显示刺激类别在150-200 ms区间、200-300 ms区间、300-400ms区间和400-500 ms区间平均波幅的主效应都显著（F值分别为7.80、13.93、6.83、36.21,P〈0.01）,通过两两比较刺激发现,无关威胁图片与中性图片在四个时间区间差异都不显著,P〉0.05,但无关威胁图片和中性图片都与威胁性冻伤图片存在显著差异：150-200ms区间[F1a（1,11）=19.10,P〈0.01;F1b（1,11）=5.78,P〈0.05]。200-300 ms区间中[F2a（1,11）=36.69,P〈0.01;F2b（1,11）=14.56,P〈0.01]。300-400 ms区间[F3a（1,11）=65.28,P〈0.01;F3b（1,11）=35.57,P〈0.01]。400-500ms区间[F4a（1,11）=36.52,P〈0.01;F4b（1,11）=53.51,P〈0.01]。结论：在疼痛情境下,接受与CPT相关的威胁性信息时脑电活动与接受中性信息和无关的威胁信息脑电图活动存在显著不同。相对无关信息刺激,与情境匹配的威胁性信息引起更多的关注和加工。这种不同不仅存在于早期的注意指向阶段,也存在于晚期的随意加工和反应选择阶段。

Objective：Pain always has cognitive components involved in the emerging and developing stages.In this study,pain induced by Cold Pressor Task（CPT）was used to study the ERPs of the threatening information.Methods：In this experiment,frostbite threatening information pictures and irrelevant information（threatening and neutral）pictures were stimuli during the CPTs.In addition,within group design was used in the experiment.Results：The research showed that there were significant differences in the brain electrical activity between the acceptance of threatening frostbite information and irrelevant information in CPT.Repeated measurement analysis of variance showed that the main effects of average amplitude were significant in 150-200ms,200-300ms,300-400ms and 400-500ms（F values were 7.80,7.80,13.93,36.21,P 0.01].By comparing the stimuli,it was found that unrelated threatening and neutral pictures in the four time intervals had no significant differences,P 0.05.But unrelated threatening pictures and neutral pictures had significant differences with threatening frostbite pictures in 150-200ms F1a（1,11）=19.10,P 0.01;F1b（1,11）=5.78,P 0.05],200-300msF2a（1,11）=36.69,P 0.01;F2b（1,11）=14.56,P 0.01].300-400ms[F3a（1,11）=65.28,P 0.01;F3b（1,11）=35.57,P 0.01]and 400-500ms[F4a（1,11）=36.52,P〈0.01;F4b（1,11）=53.51,P〈0.01].Conclusion：This study found that in CPT pain,ERPs activity from the threatening information related to CPT were significantly different from that of neutral and the threat information unrelated with the CPT.Compared with the irrelevant information picture stimuli,threatening information pictures that matched the situation caused more attention and cognitive processing.Such differences were observable not only in the early attention orienting stage,but also in the later conscious processing and responsive decision stages.