Department of Psychological Sciences, Birkbeck, University of London, Malet Street, London WC1E 7HX, UK.
Soc Cogn Affect Neurosci. 2012 Oct;7(7):752-63. doi: 10.1093/scan/nsr050. Epub 2011 Sep 6.
Behavioural findings have led to proposals that difficulties in attention and concentration in depression may have their roots in fundamental inhibitory impairments for irrelevant information. These impairments may be associated with reduced capacity to actively maintain relevant information to facilitate goal-directed behaviour. In light of mixed data from behavioural studies, the current study using direct neural measurement, examines whether dysphoric individuals show poor filtering of irrelevant information and reduced working memory (WM) capacity for relevant information. Consistent with previous research, a sustained event-related potential (ERP) asymmetry, termed contra-lateral delay activity (CDA), was observed to be sensitive to WM capacity and the efficient filtering of irrelevant information from visual WM. We found a strong positive correlation between the efficiency of filtering irrelevant items and visual WM capacity. Specifically, dysphoric participants were poor at filtering irrelevant information, and showed reduced WM capacity relative to high capacity non-dysphoric participants. Results support the hypothesis that impaired inhibition is a central feature of dysphoria and are discussed within the framework of cognitive and neurophysiological models of depression.
行为研究结果表明，抑郁患者在注意力和专注力方面的困难可能源于对无关信息的基本抑制障碍。这些障碍可能与主动维持相关信息以促进目标导向行为的能力降低有关。鉴于行为研究中的混合数据，本研究使用直接神经测量方法，检查抑郁个体是否表现出对无关信息的过滤能力差和对相关信息的工作记忆（WM）容量降低。与先前的研究一致，观察到持续的事件相关电位（ERP）不对称，称为对侧延迟活动（CDA），对 WM 容量和从视觉 WM 中有效过滤无关信息敏感。我们发现过滤无关项目的效率与视觉 WM 容量之间存在很强的正相关。具体来说，抑郁参与者在过滤无关信息方面表现不佳，与高容量非抑郁参与者相比，WM 容量降低。研究结果支持抑制受损是抑郁的核心特征这一假设，并在认知和神经生理抑郁模型的框架内进行了讨论。
