Understanding the dynamics of visual processing abnormalities in body dysmorphic disorder

项目概要/摘要 患有身体畸形恐惧症（BDD）的人会对自己的行为产生特殊的误解。 外观，通常是脸部或头部。他们被认为是毁容和丑陋的， 洞察力差，甚至妄想的信念，以及强迫性思想和强迫行为，焦虑， 萧条这些联合收割机导致严重的功能障碍，以及抑郁症，自杀 尝试（25%）和精神病住院治疗（50%）。尽管如此严重，相对较少的研究， 神经生物学，甚至治疗研究，已经在BDD中进行。这突出表明，迫切需要 旨在根据病理生理机制确定干预目标的研究。迄今为止， 背景技术我们小组进行的研究提供了对神经生物学机制的早期认识， 可能导致这些感知失真，包括视觉处理系统中的显著异常。 这些，沿着来自视觉空间和视觉的神经心理学和心理物理学测试的证据 处理，有助于发展一种减少全球/整体处理的模型， 增强的细节处理，归因于“自上而下”和“自下而上”的知觉干扰。 然而，在神经生物学的理解上仍然存在差距，这可能会阻碍理性的发展 新颖有效的治疗策略。到目前为止，研究主要是横截面的，很少有 探讨了视觉操作的影响，以探测动态异常。因此，本研究 旨在阐明BDD中感知扭曲的病理生理学基础，使用两种新的视觉 调节技术：a）注意力调节（“自上而下”）和简短的图像呈现（“自下而上”）， 探索视觉系统我们将招募34名BDD患者和34名健康对照者，他们将接受两次 实验涉及观看他们的脸部照片，同时使用功能性磁扫描仪进行扫描。 共振成像（fMRI）。在注意力调节实验中，他们将得到指导和训练 为了保持他们的注视恒定以增加注视持续时间并减少对外观细节的扫描， 我们假设这将增加背侧视觉流（全局/整体处理），减少腹侧视觉流（全局/整体处理）， 视觉流（局部/细节处理）激活大脑。在第二个实验中，我们将测试 短暂的看脸时间增加了背侧视觉区的活动。这项研究的结果将推动我们的 理解BDD中知觉扭曲的神经生物学基础，并确定神经生物学 治疗目标为未来测试的新的，翻译知觉再训练治疗。

Project Summary/Abstract Individuals suffering from body dysmorphic disorder (BDD) experience peculiar misperceptions of their appearance, most often of the face or head. With convictions of disfigurement and ugliness, they typically have poor insight or even delusional beliefs, as well as obsessive thoughts and compulsive behaviors, anxiety, and depression. These combine to result in significant difficulties in functioning, as well as depression, suicide attempts (25%), and psychiatric hospitalization (50%). Despite this severity, relatively few studies of the neurobiology, or even treatment studies, have been conducted in BDD. This underscores a critical need for research seeking to identify targets for intervention based on pathophysiological mechanisms. To-date, background research conducted by our group has provided early insights into neurobiological mechanisms that may contribute to these perceptual distortions, including prominent abnormalities in visual processing systems. These, along with evidence from neuropsychological and psychophysical tests of visuospatial and visual processing, have contributed to the development of a model of diminished global/holistic processing and enhanced detail processing, attributed to both “top-down” and “bottom-up” disturbances in perception. However, there remain gaps in the understanding of the neurobiology that may hinder the rational development of novel and effective treatment strategies. Studies thus far have primarily been cross-sectional and few have explored the effects of visual manipulation in order to probe for dynamic abnormalities. Accordingly, this study aims to illuminate the pathophysiology underlying perceptual distortions in BDD using two novel visual modulation techniques: a) attention modulation (“top-down”) and brief image presentation (“bottom-up”) to probe the visual system. We will enroll 34 individuals with BDD and 34 healthy controls, who will undergo two experiments involving viewing photographs of their face while being scanned using functional magnetic resonance imaging (fMRI). In the attention modulation experiment, they will be given instructions and training to hold their gaze constant in order to increase fixation duration and decrease scanning of appearance details, which we hypothesize will increase dorsal visual stream (global/holistic processing) and decrease ventral visual stream (local/detail processing) activation in the brain. In the second experiment we will test whether brief face viewing time increases activity in dorsal visual areas. Results from this study will advance our understanding of the neurobiological basis of perceptual distortions in BDD and identify neurobiological treatment targets for future testing of novel, translational perceptual retraining treatments.