Leung K-K, Lee T M C, Wong M M C, Li L S W, Yip P S F, Khong P-L
Laboratory of Neuropsychology, The University of Hong Kong, Hong Kong.
Psychol Med. 2009 Jul;39(7):1097-106. doi: 10.1017/S0033291708004546. Epub 2008 Oct 23.
Patients with major depressive disorder are found to show selective attention biases towards mood-congruent information. Although previous studies have identified various structural changes in the brains of these patients, it remains unclear whether the structural abnormalities are associated with these attention biases. In this study, we used voxel-based morphometry (VBM) to explore the structural correlates of attention biases towards depression-related stimuli.
Seventeen female patients with major depressive disorder and 17 female healthy controls, matched on age and intelligence, underwent magnetic resonance imaging (MRI). They also performed positive-priming (PP) and negative-priming (NP) tasks involving neutral and negative words that assessed selective attention biases. The reaction time (RT) to a target word that had been attended to or ignored in a preceding trial was measured on the PP and NP tasks respectively. The structural differences between the two groups were correlated with the indexes of attention biases towards the negative words.
The enhanced facilitation of attention to stimuli in the PP task by the negative valence was only found in the depressed patients, not in the healthy controls. Such attention biases towards negative stimuli were found to be associated with reduced gray-matter concentration (GMC) in the right superior frontal gyrus, the right anterior cingulate gyrus and the right fusiform gyrus. No differential effect in inhibition of attention towards negative stimuli in the NP task was found between the depressed patients and the healthy controls.
Specific structural abnormalities in depression are associated with their attention biases towards mood-congruent information.
研究发现，重度抑郁症患者对情绪一致信息存在选择性注意偏差。尽管先前的研究已经确定了这些患者大脑中的各种结构变化，但这些结构异常是否与这些注意偏差相关仍不清楚。在本研究中，我们使用基于体素的形态测量法（VBM）来探究对抑郁症相关刺激的注意偏差的结构相关性。
17名患有重度抑郁症的女性患者和17名年龄及智力相匹配的健康对照女性接受了磁共振成像（MRI）检查。她们还进行了涉及中性和负面词汇的正启动（PP）和负启动（NP）任务，以评估选择性注意偏差。分别在PP和NP任务中测量对前一试次中被关注或被忽略的目标词的反应时间（RT）。将两组之间的结构差异与对负面词汇的注意偏差指标进行关联分析。
仅在抑郁症患者中发现了负性效价对PP任务中刺激注意的促进作用增强，而在健康对照者中未发现。发现这种对负性刺激的注意偏差与右侧额上回、右侧前扣带回和右侧梭状回的灰质浓度（GMC）降低有关。在NP任务中，抑郁症患者和健康对照者对负性刺激的注意抑制没有差异。
抑郁症中特定的结构异常与其对情绪一致信息的注意偏差相关。
