Monk Christopher S, Nelson Eric E, McClure Erin B, Mogg Karin, Bradley Brendan P, Leibenluft Ellen, Blair R James R, Chen Gang, Charney Dennis S, Ernst Monique, Pine Daniel S
Department of Psychology, University of Michigan, 2000 East Hall, 530 Church St., Ann Arbor, MI 48109, USA.
Am J Psychiatry. 2006 Jun;163(6):1091-7. doi: 10.1176/ajp.2006.163.6.1091.
While adolescent anxiety disorders represent prevalent, debilitating conditions, few studies have explored their brain physiology. Using event-related functional magnetic resonance imaging (fMRI) and a behavioral measure of attention to angry faces, the authors evaluated differences in response between healthy adolescents and adolescents with generalized anxiety disorder.
In the primary trials of interest, 18 adolescents with generalized anxiety disorder and 15 comparison subjects of equivalent age/gender/IQ viewed angry/neutral face pairs during fMRI acquisition. Following the presentation of each face pair, subjects pressed a button to indicate whether a subsequent asterisk appeared on the same (congruent) or opposite (incongruent) side as the angry face. Reaction time differences between congruent and incongruent face trials provided a measure of attention bias to angry faces.
Relative to the comparison subjects, patients with generalized anxiety disorder manifested greater right ventrolateral prefrontal cortex activation to trials containing angry faces. Patients with generalized anxiety disorder also showed greater attention bias away from angry faces. Ventrolateral prefrontal cortex activation differences remained evident when differences in attention bias were covaried. Finally, in an examination among patients of the association between degree of anxiety and brain activation, the authors found that as ventrolateral prefrontal cortex activation increased, severity of anxiety symptoms diminished.
Adolescents with generalized anxiety disorder show greater right ventrolateral prefrontal cortex activation and attentional bias away from angry faces than healthy adolescents. Among patients, increased ventrolateral prefrontal cortex activation is associated with less severe anxiety, suggesting that this activation may serve as a compensatory response.
青少年焦虑症是常见的使人衰弱的疾病,但很少有研究探索其大脑生理学机制。作者使用事件相关功能磁共振成像(fMRI)以及一项对愤怒面孔注意力的行为测量方法,评估了健康青少年与广泛性焦虑症青少年之间的反应差异。
在主要感兴趣的试验中,18名患有广泛性焦虑症的青少年和15名年龄、性别、智商相当的对照受试者在进行fMRI扫描时观看愤怒/中性面孔对。在每对面孔呈现后,受试者按下按钮以表明随后出现的星号与愤怒面孔在同一侧(一致)还是相反侧(不一致)。一致和不一致面孔试验之间的反应时间差异提供了对愤怒面孔注意力偏差的一种测量。
相对于对照受试者,广泛性焦虑症患者在观看含有愤怒面孔的试验中,右侧腹外侧前额叶皮质激活更强。广泛性焦虑症患者对愤怒面孔的注意力偏差也更大。当对注意力偏差差异进行协变量调整后,腹外侧前额叶皮质的激活差异仍然显著。最后,在对患者焦虑程度与大脑激活之间关联的一项研究中,作者发现随着腹外侧前额叶皮质激活增加,焦虑症状的严重程度降低。
与健康青少年相比,广泛性焦虑症青少年表现出更强的右侧腹外侧前额叶皮质激活以及对愤怒面孔的注意力偏差。在患者中,腹外侧前额叶皮质激活增加与焦虑症状较轻相关,这表明这种激活可能是一种代偿反应。