大学生冷酷无情特质与奖赏加工相关性的fMRI研究

AnfMRI study onrelationship betweencallous-unemotional trait and reward processing in college students

目的:探讨大学生冷酷无情特质(CU)与大脑奖赏加工过程的关系。方法:招募在校大学生35例,采用冷酷无情特质量表评估其冷酷无情特质倾向,运用功能磁共振成像技术和金钱激励延迟任务,通过对CU量表得分、奖赏幅度、奖赏效价效应量进行相关分析以及三因素方差分析,分析CU量表得分与奖赏加工过程的关系。结果:在预期阶段右侧伏隔核区域奖赏幅度效应量与CU量表得分呈负相关(r=-0.35,P<0.05),CU得分×奖赏效价×奖赏幅度三重交互作用有统计学意义(F=2.36,P<0.05)。在相同幅度的刺激下,CU量表得分越高右侧伏隔核激活水平越低;在奖赏条件下,随着奖赏幅度的增大CU量表得分越高右侧伏隔核激活水平变化越大,而在惩罚条件下,CU量表得分越高对惩罚幅度变化越不敏感。结论:冷酷无情特质得分与个体对于奖赏幅度的感知密切相关,且在奖赏过程中比惩罚过程中更显著,同时这一差别主要在奖赏的预期阶段,而不是反馈阶段。

Objective:To explore the relationship between the callous-unemotional trait(CU) and brain reward processing.Methods:Totally 35 college students were recruited and the CU scale was used to measure the level of CU.The functional magnetic resonance imaging and monetary incentive delay task was used.Correlation analysis of the score of CU,reward magnitude and reward valance effect,and the three factors ANOVA of CU score × reward valance × reward magnitude was further carried out to analyze the relationship between CU score and reward processing.Results:There was a significant negative correlation between the effect of reward magnitude and the CU scores in the right nucleus accumbens region at the stage of reward expectation(r=-0.35,P<0.05),The interaction of CU score × reward valance × reward magnitude was significant(F=2.36,P<0.05).Under the same magnitude stimulation of reward condition,the higher the CU score was,the lower the activation level of the right nucleus accumbens was,and under the penalty condition,the higher the CU score,the less sensitive it was to change in the penalty magnitude.Conclusion:Callous-unemotional trait score is closely related to the individual perception of reward magnitude,and it is more significant in the reward process than punishment process.And the difference lies mainly in the expected stage of the reward.