Liu Juntong, Wang Jinxia, Song Yuchen, Becker Benjamin, Ming Xianchao, Lei Yi
College of Psychology, Shenzhen University, Shenzhen, China.
Center for Neurogenetics, Shenzhen Institute of Neuroscience, Shenzhen, China.
Psychol Med. 2025 Apr 14;55:e116. doi: 10.1017/S0033291725000728.
Compulsive cleaning is a characteristic symptom of a particular subtype of obsessive-compulsive disorder (OCD) and is often accompanied by intense disgust. While overgeneralization of threat is a key factor in the development of obsessive-compulsive symptoms, previous studies have primarily focused on fear generalization and have rarely examined disgust generalization. A systematic determination of the behavioral and neural mechanisms underlying disgust generalization in individuals with contamination concern is crucial for enhancing our understanding of OCD.
In this study, we recruited 27 individuals with high contamination concerns and 30 individuals with low contamination concerns. Both groups performed a disgust generalization task while undergoing functional magnetic resonance imaging (fMRI).
The results revealed that individuals with high contamination concern had higher disgust expectancy scores for the generalization stimulus GS4 (the stimulus most similar to CS+) and exhibited higher levels of activation in the left insula and left putamen. Moreover, the activation of the left insula and putamen were positively correlated with a questionnaire core of the ratings of disgust and also positively correlated with the expectancy rating of CS+ during the generalization stage.
Hyperactivation of the insula and putamen during disgust generalization neutrally mediates the higher degree of disgust generalization in subclinical OCD individuals. This study indicates that altered disgust generalization plays an important role in individuals with high contamination concerns and provides evidence of the neural mechanisms involved. These insights may serve as a basis for further exploration of the pathogenesis of OCD in the future.
强迫性清洁是强迫症（OCD）特定亚型的特征性症状，常伴有强烈的厌恶情绪。虽然威胁的过度泛化是强迫症状发展的关键因素，但以往研究主要集中在恐惧泛化，很少研究厌恶泛化。系统确定有污染担忧个体中厌恶泛化的行为和神经机制，对于增进我们对强迫症的理解至关重要。
在本研究中，我们招募了27名有高污染担忧的个体和30名有低污染担忧的个体。两组在进行功能磁共振成像（fMRI）时都执行了厌恶泛化任务。
结果显示，有高污染担忧的个体对泛化刺激GS4（与CS+最相似的刺激）有更高的厌恶预期分数，并且在左侧脑岛和左侧壳核表现出更高水平的激活。此外，左侧脑岛和壳核的激活与厌恶评分问卷核心呈正相关，也与泛化阶段CS+的预期评分呈正相关。
厌恶泛化过程中脑岛和壳核的过度激活在神经层面介导了亚临床强迫症个体更高程度的厌恶泛化。本研究表明，改变的厌恶泛化在有高污染担忧的个体中起重要作用，并提供了相关神经机制的证据。这些见解可能为未来进一步探索强迫症的发病机制奠定基础。
