Anorexia nervosa (AN) and body dysmorphic disorder (BDD) are characterized by distorted perception of appearance, yet no studies have directly compared the neurobiology associated with body perception. We compared AN and BDD in brain activation and connectivity in relevant networks when viewing images of others’ bodies and tested their relationships with clinical symptoms and subjective appearance evaluations. We acquired fMRI data from 64 unmedicated females (20 weight-restored AN, 23 BDD, 21 controls) during a matching task using unaltered or spatial-frequency filtered photos of others’ bodies. Using general linear model and independent components analyses we compared brain activation and connectivity in visual, striatal, and parietal networks and performed univariate and partial least squares multivariate analyses to investigate relationships with clinical symptoms and appearance evaluations. AN and BDD showed partially overlapping patterns of hyperconnectivity in the dorsal visual network and hypoconnectivity in parietal network compared with controls. BDD, but not AN, demonstrated hypoactivity in dorsal visual and parietal networks compared to controls. Further, there were significant activity and connectivity differences between AN and BDD in both networks. In both groups, activity and/or connectivity were associated with symptom severity and appearance ratings of others’ bodies. Thus, AN and BDD demonstrate both distinct and partially-overlapping aberrant neural phenotypes involved in body processing and visually encoding global features. Nevertheless, in each disorder, aberrant activity and connectivity show relationships to clinically relevant symptoms and subjective perception. These results have implications for understanding distinct and shared pathophysiology underlying perceptual distortions of appearance and may inform future novel treatment strategies.

神经性厌食症 (AN) 和躯体变形障碍 (BDD) 的特征是对外表的感知扭曲，但尚无研究直接比较与躯体感知相关的神经生物学。我们在查看他人身体图像时比较了 AN 和 BDD 在相关网络中的大脑激活和连接性，并测试了它们与临床症状和主观外观评估的关系。我们在匹配任务中使用其他人身体的未更改或空间频率过滤照片从 64 名未接受药物治疗的女性（20 名恢复体重的 AN、23 名 BDD、21 名对照）获取了 fMRI 数据。使用一般线性模型和独立成分分析，我们比较了视觉、纹状体、和顶叶网络，并进行单变量和偏最小二乘多变量分析，以研究与临床症状和外观评估的关系。与对照组相比，AN 和 BDD 显示出部分重叠的背侧视觉网络超连接模式和顶叶网络低连接模式。与对照组相比，BDD 而不是 AN 在背侧视觉和顶叶网络中表现出活动减退。此外，两个网络中的 AN 和 BDD 之间存在显着的活动和连接差异。在两组中，活动和/或连通性与症状严重程度和他人身体的外观评级相关。因此，AN 和 BDD 展示了参与身体处理和视觉编码全局特征的不同和部分重叠的异常神经表型。尽管如此，在每种疾病中，异常活动和连接都显示出与临床相关症状和主观感知的关系。这些结果对理解外观感知扭曲背后的不同和共同的病理生理学具有重要意义，并可能为未来的新治疗策略提供信息。