情绪记忆性别差异的功能磁共振成像研究

Functional MRI study of sex-related differences in emotional memory

目的通过检测参与情绪记忆相关激活脑区,探讨情绪记忆中性别差异相关的特异性脑机制。方法20名健康被试,实验包括编码和提取两阶段,同时实行功能MRI扫描及记录行为学成绩,利用SPM2对功能数据进行方差分析和简单相关分析。结果男性情绪记忆成功编码主要与右侧杏仁核相关,女性主要与左侧杏仁核相关。男女记忆增强效应均与左侧杏仁核明显相关。男性多激活前额叶不同亚区皮层,而女性多激活杏仁核、海马、梭状回和枕部皮层。结论情绪记忆中杏仁核激活存在男右女左偏侧化优势;这种偏侧化效应在两性的情绪记忆增强效应中不起主要作用。大脑前后部皮层激活也存在性别差异,男女性情绪记忆加工存在相对特异性神经机制。

Objective To explore the specific neural mechanisms related to the sex differences in the emotional memory via examining the brain regions correlated with emotional memory processing. Methods Twenty normal subjects participated in the study which included encoding and retrieval stages. Functional MRI scans were conducted along with the behavioral performance recorded and the functional data were dealt with SPM2 and analyzed by ANOVA and simple correlation. Results The successful encoding involved the left amygdala in women while the right one in men. The activity of left amygdala was correlated with memory enhancement effects in women and men. Additionally significantly various prefrontal sub-cortices were activated in men, while more brain regions including amygdala, hippocampus, fusiform gyrus and occipital cortex were activated in women predominantly. Conclusion Amygdala involvement in emotional memory exhibits female-left/male-right lateralization, while the enhancement effect is not related to sex-related hemisphere specialization of the amygdala directly. The gender differences in the anterior brain regions and the posterior cerebral cortex are associated with the distinct cognitive modulations between the sexes.