Department of Psychology, University of New Mexico, Albuquerque, NM 87131, USA.
Clin Neurophysiol. 2011 Jan;122(1):107-13. doi: 10.1016/j.clinph.2010.05.027. Epub 2010 Jun 26.
An abnormally increased activation in anterior brain networks, accompanied by normal task performance, has been reported in studies on biological mechanisms of obsessive-compulsive disorder (OCD). We test a hypothesis, that this phenomenon, deemed specific to OCD, will be compromised by a very difficult task, which may lead to reduced cortical information processing and erroneous performance, as found in other disorders such as schizophrenia.
We designed a new variant of high-conflict Stroop-word-color interference task (Stroop-WCIT) with each incongruent (INC) trial preceded by multiple congruent trials. Event-related potentials (ERPs) were acquired from subjects with OCD and case-matched healthy controls (C). We analyzed ERPs elicited by correct responses to conflict-related INC trials.
Our hypothesis found no support. Although the anterior ERPs N200, a negative component within 140-300 ms latency window, was significantly abnormally increased in OCD subjects, their performance accuracy remained normal.
Current findings suggest an enhanced adaptive top-down control in OCD mediated by the prefrontal lateral and dorsal anterior cingulate networks.
Further studies are warranted to test the hypothesis that increased activity within the anterior network for top-down inhibitory control in OCD may be a part of an adaptive compensatory neural mechanism.
在强迫症（OCD）的生物学机制研究中，有报道称前脑网络的异常激活伴随着正常的任务表现。我们检验了一个假设，即这种被认为是 OCD 特有的现象，在非常困难的任务下会受到影响，这可能会导致皮质信息处理减少和错误表现，就像在其他疾病如精神分裂症中发现的那样。
我们设计了一种新的高冲突 Stroop 词色干扰任务（Stroop-WCIT）变体，每个不匹配（INC）试验前都有多个匹配试验。强迫症患者和病例匹配的健康对照组（C）的受试者接受了事件相关电位（ERPs）采集。我们分析了与冲突相关的 INC 试验中正确反应引起的 ERP。
我们的假设没有得到支持。尽管 OCD 患者的前脑 ERP N200（140-300ms 潜伏期窗口内的负成分）明显异常增加，但他们的表现准确性仍保持正常。
目前的研究结果表明，OCD 中前额叶外侧和背侧前扣带网络介导的适应性自上而下控制增强。
需要进一步的研究来检验 OCD 中用于自上而下抑制控制的前网络中活动增加可能是适应性补偿神经机制的一部分的假设。
