抑郁症患者工作记忆内情绪刺激加工的特点及其机制

抑郁症患者在工作记忆内情绪刺激加工的特点为倾向于加工与负性心境一致的材料, 被认为是抑郁症认知易感性的核心特征。目前研究者们围绕抑郁症工作记忆中央执行系统三个子功能的情绪刺激加工特点及其作用机制进行了大量研究, 发现在更新功能上, 患者难以移除负性情绪信息, 且在正性信息的加工上存在缺损; 在抑制功能上, 患者难以抑制无关负性情绪信息进入工作记忆; 在转换功能上, 患者情绪材料转换困难的研究证据尚不充分。神经生理与脑成像的研究初步表明, 工作记忆中的情绪刺激加工与抑郁症患者背外侧前额叶和前扣带回的功能激活水平异常有关。未来研究需评估工作记忆三个子功能对抑郁症状的差异性贡献及在情绪刺激加工上的统一性, 并探究其随疾病发生发展变化的轨迹, 谨慎选取并评估不同情绪刺激材料指标的诱发效应及其对工作记忆功能的独特影响。在此基础上, 深入探究工作记忆内情绪刺激加工的神经机制, 为工作记忆偏向矫正干预的临床应用及其预期效果提供理论依据和方向。

Processing of emotional information in working memory in major depressive disorder

Major Depressive Disorder(MDD)is associated with mood-congruent processing biases towards negative information in working memory(WM),which is considered as the core manifest of cognitive vulnerability of MDD.This review provides an overview of the biased processing of emotional information of depression in three executive components of WM.Patients with MDD have difficulties in disengaging from negative information and present insufficient processing of positive materials during WM updating.MDD patients also exhibit impairments in suppressing irrelevant negative information and cannot effectively prevent the irrelevant negative information entering WM during inhibition.The findings of emotion-specific dysfunctions of shifting function in depression are inconsistent.Electrophysiological and neuroimaging studies suggest that the biased processing in WM is associated with altered brain activations in dorsolateral prefrontal cortex and anterior cingulate cortex.Future research is needed to investigate the different contribution of each type of biased processing to depressive symptoms,the unity of the biased processing in three WM components,the impact of biased processing in different stages of MDD,and the induction effects of different emotional materials on biased processing.Moreover,unraveling the neurophysiological mechanisms underlying the process of emotional materials in WM could help resolve the inconsistency of previous findings and benefit future development of cognitive bias modification interventions for biased processing in WM of depression.