Department of Psychiatry, University of Cambridge School of Clinical Medicine, Addenbrooke's Hospital, Cambridge, UK.
Psychol Med. 2010 Feb;40(2):263-72. doi: 10.1017/S003329170999033X. Epub 2009 Jul 2.
Obsessive-compulsive disorder (OCD) has been associated with impairments in stop-signal inhibition, a measure of motor response suppression. The study used a novel paradigm to examine both thought suppression and response inhibition in OCD, where the modulatory effects of stimuli relevant to OCD could also be assessed. Additionally, the study compared inhibitory impairments in OCD patients with and without co-morbid depression, as depression is the major co-morbidity of OCD.
Volitional response suppression and unintentional thought suppression to emotive and neutral stimuli were examined using a novel thought stop-signal task. The thought stop-signal task was administered to non-depressed OCD patients, depressed OCD patients and healthy controls (n=20 per group).
Motor inhibition impairments were evident in OCD patients, while motor response performance did not differ between patients and controls. Switching to a new response but not motor inhibition was affected by stimulus relevance in OCD patients. Additionally, unintentional thought suppression as measured by repetition priming was intact. OCD patients with and without depression did not differ on any task performance measures, though there were significant differences in all self-reported measures.
Results support motor inhibition deficits in OCD that remain stable regardless of stimulus meaning or co-morbid depression. Only switching to a new response was influenced by stimulus meaning. When response inhibition was successful in OCD patients, so was the unintentional suppression of the accompanying thought.
强迫症（OCD）与停止信号抑制受损有关，停止信号抑制是一种运动反应抑制的测量方法。该研究使用一种新的范式来检查 OCD 中的思维抑制和反应抑制，其中也可以评估与 OCD 相关的刺激的调节作用。此外，该研究比较了伴有和不伴有共病抑郁症的 OCD 患者的抑制障碍，因为抑郁症是 OCD 的主要共病。
使用一种新的思维停止信号任务来检查情绪和中性刺激的意志反应抑制和无意识思维抑制。思维停止信号任务被施用于非抑郁性 OCD 患者、抑郁性 OCD 患者和健康对照组（每组 20 人）。
在 OCD 患者中明显存在运动抑制障碍，而患者和对照组之间的运动反应表现没有差异。在 OCD 患者中，刺激相关性影响了对新反应的转换，但不影响运动抑制。此外，通过重复启动测量的无意识思维抑制是完整的。伴或不伴抑郁的 OCD 患者在任何任务表现测量上均无差异，尽管所有自我报告的测量均存在显著差异。
结果支持 OCD 中的运动抑制缺陷，这些缺陷在刺激意义或共病抑郁症的情况下保持稳定。只有转换到新的反应才受到刺激意义的影响。当 OCD 患者成功进行反应抑制时，伴随的思维也会无意识地被抑制。
