Department of Neuropsychiatry, Seoul National University Hospital, Seoul, Republic of Korea; Department of Clinical Medical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea.
Department of Brain and Cognitive Sciences, Seoul National University College of Natural Sciences, Seoul, Republic of Korea.
Neuroimage Clin. 2024;43:103644. doi: 10.1016/j.nicl.2024.103644. Epub 2024 Jul 18.
Obsessive-compulsive disorder (OCD) is a heterogeneous condition characterized by distinct symptom subtypes, each with varying pathophysiologies and treatment responses. Recent research has highlighted the role of the amygdala, a brain region that is central to emotion processing, in these variations. However, the role of amygdala subregions with distinct functions has not yet been fully elucidated. In this study, we aimed to clarify the biological mechanisms underlying OCD subtype heterogeneity by investigating the functional connectivity (FC) of amygdala subregions across distinct OCD symptom subtypes.
Resting-state functional magnetic resonance images were obtained from 107 medication-free OCD patients and 110 healthy controls (HCs). Using centromedial, basolateral, and superficial subregions of the bilateral amygdala as seed regions, whole-brain FC was compared between OCD patients and HCs and among patients with different OCD symptom subtypes, which included contamination fear and washing, obsessive (i.e., harm due to injury, aggression, sexual, and religious), and compulsive (i.e., symmetry, ordering, counting, and checking) subtypes.
Compared to HCs, compulsive-type OCD patients exhibited hypoconnectivity between the left centromedial amygdala (CMA) and bilateral superior frontal gyri. Compared with patients with contamination fear and washing OCD subtypes, patients with compulsive-type OCD showed hypoconnectivity between the left CMA and left frontal cortex.
CMA-frontal cortex hypoconnectivity may contribute to the compulsive presentation of OCD through impaired control of behavioral responses to negative emotions. Our findings underscored the potential significance of the distinct neural underpinnings of different OCD manifestations, which could pave the way for more targeted treatment strategies in the future.
强迫症（OCD）是一种表现出不同症状亚型的异质性疾病，每种亚型都具有不同的病理生理学和治疗反应。最近的研究强调了杏仁核在这些变化中的作用，杏仁核是大脑中负责情绪处理的关键区域。然而，具有不同功能的杏仁核亚区的作用尚未得到充分阐明。在这项研究中，我们旨在通过研究不同 OCD 症状亚型的杏仁核亚区的功能连接（FC）来阐明 OCD 亚型异质性的生物学机制。
对 107 名未服药的 OCD 患者和 110 名健康对照者（HCs）进行静息态功能磁共振成像（rs-fMRI）检查。使用双侧杏仁核的中央核、基底外侧核和浅层亚区作为种子区域，比较 OCD 患者和 HCs 之间以及不同 OCD 症状亚型（包括污染恐惧和洗涤、强迫（即伤害、攻击、性和宗教引起的）和强迫（即对称、排序、计数和检查）之间的全脑 FC。
与 HCs 相比，强迫型 OCD 患者的左侧杏仁核中央核（CMA）与双侧额上回之间的连接减少。与污染恐惧和洗涤 OCD 亚型的患者相比，强迫型 OCD 患者的左侧 CMA 与左侧额叶皮质之间的连接减少。
CMA-前额叶皮质连接减少可能通过损害对负面情绪的行为反应控制导致 OCD 的强迫表现。我们的发现强调了不同 OCD 表现的不同神经基础的潜在意义，这可能为未来更有针对性的治疗策略铺平道路。
