情绪动机方向诱发额叶皮质不对称激活的神经机制研究

Electroencephalogram mechanism of asymmetric activation of frontal cortex induced by emotional motivation

目的考察个体在高趋近动机和高趋避动机情绪条件下的注意力捕获和情绪感知脑区不对称性激活的潜在神经生理机制。方法26名被试观看三类典型情境图片(美食、恐惧、中性)后诱发相应的高趋近动机、高趋避动机和中性情绪,并记录其脑电数据。结果对于P1波幅,高趋近动机、高趋避动机、中性情绪状态下三者之间波幅差异有统计学意义(P<0.001)。对于P2和LPP波幅,高趋近动机和高趋避动机情绪状态分别与中性情绪的波幅差异有统计学意义(P<0.001),但前两者之间差异无统计学意义。进一步分析显示,高趋近动机情绪在左前额区,而高趋避动机情绪在右前额区,相比中性情绪诱发了更大的LPP波幅。结论早期感觉加工阶段,高趋避动机情绪在视觉皮质纹外区占用更多的注意资源。中期和晚期的注意分配阶段,高趋近动机与高趋避动机情绪的激活过程促进了注意力的分配和信息资源的获取,且在晚期阶段,高趋近动机情绪在左前额区而高趋避动机情绪在右前额区表现出更强的情绪感知力,表明前额皮质区域对情绪动机方向处理的不对称性。

Objective To investigate the differences of potential neuroelectrophysiological mechanism in individuals′attention capture and emotion perception of asymmetric activation under the conditions of high-approach motivated and high-withdrawal motivated emotions.Methods 26 undergraduates watched pictures of three typical situations(food,fear and neutral)and then induced the corresponding motivations(high-approach motivated emotion,high-withdrawal motivated emotion and neutral emotion),as well as recorded their EEG data.Results For P1 amplitude,there was statistically significant difference in the averaged amplitude among the three states(P<0.001).For P2 and LPP amplitudes,the emotional states of high-approach motivated emotion and high-withdrawal motivated emotion were significantly different than those of neutral emotion(P<0.001),but there was no statistically significant difference between the former two states.Further analysis showed that the LPP amplitude was larger in the right prefrontal region than in the left prefrontal region,while the LPP amplitude was larger in the right prefrontal region than in the neutral one.Conclusion In the early stage of sensory processing,high-withdrawal motivated emotion takes up more attention resources in the extramural area of visual cortex.In the middle and late stages of attention distribution,the emotional activation of high-approach motivated emotion and the high-withdrawal motivated emotion promotes the allocation of attention and the acquisition of information resources.In the late stage,high-approach motivated emotion in the left prefrontal area and high withdrawal-motivated emotion in right prefrontal area show a stronger emotional perception,suggesting the prefrontal cortex responses for the asymmetry of emotional motivation direction.