Department of Psychiatry, Neuroscience Campus Amsterdam, VU University Medical Center, Amsterdam, The Netherlands.
Psychol Med. 2011 Nov;41(11):2399-410. doi: 10.1017/S0033291711000535. Epub 2011 May 5.
Direct comparisons of brain function between obsessive compulsive disorder (OCD) and other anxiety or OCD spectrum disorders are rare. This study aimed to investigate the specificity of altered frontal-striatal and limbic activations during planning in OCD, a prototypical anxiety disorder (panic disorder) and a putative OCD spectrum disorder (hypochondriasis).
The Tower of London task, a 'frontal-striatal' task, was used during functional magnetic resonance imaging measurements in 50 unmedicated patients, diagnosed with OCD (n=22), panic disorder (n=14) or hypochondriasis (n=14), and in 22 healthy subjects. Blood oxygen level-dependent (BOLD) signal changes were calculated for contrasts of interest (planning versus baseline and task load effects). Moreover, correlations between BOLD responses and both task performance and state anxiety were analysed.
Overall, patients showed a decreased recruitment of the precuneus, caudate nucleus, globus pallidus and thalamus, compared with healthy controls. There were no statistically significant differences in brain activation between the three patient groups. State anxiety was negatively correlated with dorsal frontal-striatal activation. Task performance was positively correlated with dorsal frontal-striatal recruitment and negatively correlated with limbic and ventral frontal-striatal recruitment. Multiple regression models showed that adequate task performance was best explained by independent contributions from dorsolateral prefrontal cortex (positive correlation) and amygdala (negative correlation), even after controlling for state anxiety.
Patients with OCD, panic disorder and hypochondriasis share similar alterations in frontal-striatal brain regions during a planning task, presumably partly related to increased limbic activation.
强迫症（OCD）与其他焦虑症或 OCD 谱系障碍之间的大脑功能直接比较很少。本研究旨在研究在 OCD（惊恐障碍）、典型焦虑症（惊恐障碍）和假定的 OCD 谱系障碍（疑病症）中计划过程中改变的额纹状体和边缘激活的特异性。
在 50 名未经治疗的患者（强迫症（n=22）、惊恐障碍（n=14）或疑病症（n=14）和 22 名健康受试者）的功能磁共振成像测量期间，使用伦敦塔任务（一种“额纹状体”任务）。计算感兴趣对比（计划与基线和任务负荷效应）的血氧水平依赖性（BOLD）信号变化。此外，还分析了 BOLD 反应与任务表现和状态焦虑之间的相关性。
总的来说，与健康对照组相比，患者的楔前叶、尾状核、苍白球和丘脑的募集减少。三组患者之间的大脑激活没有统计学上的显著差异。状态焦虑与背侧额纹状体激活呈负相关。任务表现与背侧额纹状体募集呈正相关，与边缘和腹侧额纹状体募集呈负相关。多元回归模型表明，任务表现良好主要由背外侧前额叶皮层（正相关）和杏仁核（负相关）的独立贡献来解释，即使在控制状态焦虑后也是如此。
强迫症、惊恐障碍和疑病症患者在计划任务中表现出相似的额纹状体区域改变，这可能部分与边缘激活增加有关。
