Fu Cynthia H Y, Williams Steve C R, Brammer Michael J, Suckling John, Kim Jieun, Cleare Anthony J, Walsh Nicholas D, Mitterschiffthaler Martina T, Andrew Chris M, Pich Emilio Merlo, Bullmore Edward T
Institute of Psychiatry, King's College London, 103 Denmark Hill, London SE5 8AF, UK.
Am J Psychiatry. 2007 Apr;164(4):599-607. doi: 10.1176/ajp.2007.164.4.599.
Processing affective facial expressions is an important component of interpersonal relationships. However, depressed patients show impairments in this system. The present study investigated the neural correlates of implicit processing of happy facial expressions in depression and identified regions affected by antidepressant therapy.
Two groups of subjects participated in a prospective study with functional magnetic resonance imaging (fMRI). The patients were 19 medication-free subjects (mean age, 43.2 years) with major depression, acute depressive episode, unipolar subtype. The comparison group contained 19 matched healthy volunteers (mean age, 42.8 years). Both groups underwent fMRI scans at baseline (week 0) and at 8 weeks. Following the baseline scan, the patients received treatment with fluoxetine, 20 mg daily. The fMRI task was implicit affect recognition with standard facial stimuli morphed to display varying intensities of happiness. The fMRI data were analyzed to estimate the average activation (overall capacity) and differential response to variable intensity (dynamic range) in brain systems involved in processing facial affect.
An attenuated dynamic range of response in limbic-subcortical and extrastriate visual regions was evident in the depressed patients, relative to the comparison subjects. The attenuated extrastriate cortical activation at baseline was increased following antidepressant treatment, and symptomatic improvement was associated with greater overall capacity in the hippocampal and extrastriate regions.
Impairments in the neural processing of happy facial expressions in depression were evident in the core regions of affective facial processing, which were reversed following treatment. These data complement the neural effects observed with negative affective stimuli.
处理情感性面部表情是人际关系的一个重要组成部分。然而，抑郁症患者在这个系统中存在缺陷。本研究调查了抑郁症患者对快乐面部表情的内隐加工的神经关联，并确定了受抗抑郁治疗影响的区域。
两组受试者参与了一项使用功能磁共振成像（fMRI）的前瞻性研究。患者为19名未服用药物的重度抑郁症、急性抑郁发作、单相亚型患者（平均年龄43.2岁）。对照组包含19名匹配的健康志愿者（平均年龄42.8岁）。两组在基线（第0周）和第8周时均接受了fMRI扫描。在基线扫描后，患者接受每日20毫克氟西汀的治疗。fMRI任务是对标准面部刺激进行内隐情感识别，这些刺激经过变形以显示不同强度的快乐表情。对fMRI数据进行分析，以估计参与处理面部情感的脑系统中的平均激活（总体能力）和对可变强度的差异反应（动态范围）。
与对照组相比，抑郁症患者在边缘 - 皮层下和纹外视觉区域的反应动态范围减弱。抗抑郁治疗后，基线时减弱的纹外皮层激活增加，症状改善与海马和纹外区域更大的总体能力相关。
抑郁症患者对快乐面部表情的神经加工缺陷在情感性面部加工的核心区域明显，治疗后这些缺陷得到逆转。这些数据补充了在负面情感刺激下观察到的神经效应。
