Faculty of Psychology, Southwest University (SWU), Chongqing, China; Key Laboratory of Cognitive and Personality (SWU), Ministry of Education, Chongqing, China.
Bioimaging Core, Faculty of Health Sciences, University of Macau, Taipa, Macau SAR, China.
Behav Res Ther. 2017 Oct;97:96-104. doi: 10.1016/j.brat.2017.07.011. Epub 2017 Jul 20.
The neural mechanism underlying attentional bias in OCD (Obsessive-Compulsive Disorder) remains unclear. The goal of this study was to examine and compare the time course and the event related potential (ERP) components in OCD patients and healthy controls (HC) to reveal the complex brain activation pattern associated with attentional bias in OCD. The behavioural and electroencephalogram (EEG) data were recorded while the participants performed an emotional Stroop task. Compared to HC, the individuals with OCD exhibited slower response time, prolonged N1 latency and larger N1 and P2 amplitudes across different emotional words. In addition, we discovered that the OCD group showed an enlarged N1 component to OCD-related threat words compared to neutral words. Moreover, the OCD group had decreased P3 and later positive potential (LPP) amplitudes towards all types of words compared to the HC group. More importantly, the OCD group manifested smaller LPP amplitude to threat words compared to the HC group. Our findings suggest that OCD individuals may excessively direct their attention away from the threat at the late processing stage, probably due to the intensive processing or overestimation of the stimuli in the early automatic processing stage.
强迫症（OCD）患者注意偏向的神经机制尚不清楚。本研究旨在比较强迫症患者和健康对照组（HC）在时间进程和事件相关电位（ERP）成分方面的差异，以揭示与 OCD 注意偏向相关的复杂大脑激活模式。在参与者进行情绪 Stroop 任务时，记录了行为和脑电图（EEG）数据。与 HC 相比，OCD 患者在不同情绪词上表现出较慢的反应时间、较长的 N1 潜伏期以及更大的 N1 和 P2 振幅。此外，我们发现 OCD 组对 OCD 相关威胁词的 N1 成分大于对中性词的 N1 成分。此外，与 HC 组相比，OCD 组对所有类型的词的 P3 和后期正电位（LPP）振幅均降低。更重要的是，与 HC 组相比，OCD 组对威胁词的 LPP 振幅较小。我们的研究结果表明，OCD 个体可能在晚期处理阶段过度将注意力从威胁上转移开，这可能是由于在早期自动处理阶段对刺激的密集处理或高估。
