Common and Distinct Phenotypes of Body Dysmorphic Disorder and Anorexia Nervosa

描述（由申请人提供）：本研究的目的是通过一组功能神经影像学实验来表征与身体畸形障碍（BDD）和神经性厌食症（AN）相关的共享和独特的脑回路。BDD和神经性厌食症是严重的致残性精神疾病，它们有许多共同的临床特征，如扭曲的身体形象和对自我价值的外表高估，但它们目前被分为不同的诊断类别。尽管它们的发病率和死亡率都很高，但为了了解这些疾病共享和独特临床表型的潜在神经生物学，很少有研究对它们进行比较和对比。BDD和An的一个重要的共同临床表型是外观感知扭曲，这可能导致身体形象扭曲。早期有证据表明，BDD和AN在视觉感知和视觉空间加工方面存在类似的共同表型障碍，这在临床和神经心理学测试中得到了证实。然而，对介导这些的潜在神经生物学过程知之甚少。一项针对成年BDD患者的初步功能性磁共振成像（fMRI）研究表明，当他们看到他人的面孔时，负责高细节处理的左半球区域出现异常激活。最近一项关于BDD的研究表明，在看自己的脸时，初级情绪处理区域没有异常。另一方面，AN通常表现为早期儿童期的焦虑，以及对体重增加的极度恐惧。然而，没有研究专门研究过AN中的恐惧处理过程，也没有将其与BDD进行比较。本研究的目的是确定BDD和AN中视觉和情绪处理的共同和独特的表型，这些表型映射到特定的大脑系统。本研究将招募25名BDD患者、25名体重恢复型AN患者和25名健康对照，年龄在18-30岁之间。功能性磁共振成像（fMRI）将用于识别与视觉和情绪处理相关的大脑系统中的关键异常。基于先前在BDD中的fMRI研究，以及我们的试点数据和先前表明AN中细节处理异常的研究，本研究将使用不同类型的视觉图像来研究他人的面部、身体和非面部物体（房屋）的视觉处理，这些视觉图像传达了高、低或正常的细节水平。为了比较和对比情绪处理的模式，本研究将使用恐惧面孔刺激来了解与情绪反应、调节和习惯化相关的常见或独特的大脑活动模式。

DESCRIPTION (provided by applicant): The purpose of this study is to characterize shared and unique brain circuits associated with Body Dysmorphic Disorder (BDD) and Anorexia Nervosa (AN) using a set of functional neuroimaging experiments. BDD and anorexia nervosa AN are severe and disabling psychiatric disorders that share many clinical features such as distorted body image and overvaluation of appearance for self-worth, yet they are currently classified in separate diagnostic categories. Despite their significant morbidity and mortality, very little research has been conducted to compare and contrast these disorders in order to understand the underlying neurobiology of shared and unique clinical phenotypes. An important shared clinical phenotype in BDD and AN is perceptual distortion of appearance, which may contribute to distorted body image. There is early evidence of similar, common phenotypes of disturbances in visual perception and visuospatial processing in BDD and AN, as evidenced clinically and from neuropsychological testing. However, little is known of the underlying neurobiological processes that mediate these. A preliminary functional magnetic resonance imaging (fMRI) study in adults with BDD demonstrated abnormal activation in left hemisphere regions responsible for high-detail processing when viewing others' faces. A more recent study in BDD demonstrated no abnormalities of primary emotional processing regions when viewing own-faces. AN, on the other hand, is often characterized by early, childhood-onset anxiety in addition to extreme fears of weight gain. However, no study has specifically examined fear processing in AN nor compared it to BDD. The goal of the proposed study is to define the common and distinct and phenotypes of visual and emotional processing in BDD and AN that map onto specific brain systems. This study will enroll 25 subjects with BDD, 25 with weight-restored AN, and 25 healthy controls, ages 18-30. Functional magnetic resonance imaging (fMRI) will be used to identify key abnormalities in brain systems associated with visual and emotional processing. Based on previous fMRI research in BDD, and our pilot data and previous studies suggesting abnormalities of detail-processing in AN, this study will investigate visual processing of others' faces, bodies, and non-face objects (houses) using different types of visual images that convey high, low, or normal level of detail. To compare and contrast patterns of emotional processing, this study will use fearful face stimuli to understand common or distinct brain activity patterns associated with emotional reactivity, regulation, and habituation. . PUBLIC HEALTH RELEVANCE: This study will characterize brain circuitry associated with perceptual distortions and emotional processing in these severe and disabling disorders of body image to establish the neural basis for their shared and distinct clinical features. This will assist in refining classification schemes based on an understanding of underlying brain mechanisms and not merely surface symptoms and behaviors. It will also lay the foundation for future development of novel therapeutics such as perceptual retraining and emotion regulation techniques.