No Way Around But Through: Mechanisms of Persistence and Remission of Habits in Anorexia Nervosa

神经性厌食症是一种严重的疾病，其死亡率在所有精神科疾病中名列前茅。 生病了。AN的发病率和死亡率的核心是一种持续的倾向，即将热量摄入量限制在 身体的需要，有一种特殊的倾向，限制来自脂肪的卡路里。这种令人费解的行为 拒绝改变，即使接受了完整的住院治疗和体重恢复。此外， 严格的饮食习惯与出院后的高复发率有关。为了提高 考虑到预后和长期缓解率，更好地了解疾病的病理生理学是至关重要的。这 该提案专门旨在阐明导致疾病永久化的机制， 相反，持续缓解。持续不适应行为的一个可能机制是习惯 队形，通过这种方式，习得的行为对目标变得相对不敏感。习惯行为与 与背侧额纹系统的神经活动有关。在这里，我们将评估习惯性行为和目标导向行为 通过三个实验，深入评估行为和神经机制， 支持疾病的坚持，以及疾病的缓解。这款综合电池包括一个 增加两步决策任务以评估习惯性行为与目标导向行为的优势 (修改以提高习惯敏感度)，回避习惯任务，以评估习惯形成在设置 厌恶结果和巴甫洛夫工具性迁移任务，以评估背景线索的强度 加剧习惯性行为。任务组还将测量一般异常与特定于食品的异常。 我们的中心假设是，习惯有助于疾病的持久存在，而目标导向 行为有助于缓解病情。检查与短和短相关的大脑和行为特征 长期缓解，我们利用我们的长期研究部门，该部门有一个成功的计划，完全 体重恢复(急性缓解)，并有一个已经存在了一年多的研究登记处 十年。我们将使用我们的任务组通过功能磁共振成像来急性恢复AN(n=80)住院患者的体重。 长期缓解的个人(n=40，从研究登记中心招募)，以及健康 对照女性(HC，n=40)。我们还将邀请研究登记中所有符合条件的患者(n=397， 目前)在线完成我们的任务组，以便评估习惯性行为与目标导向行为之间的关系 大样本，涵盖从复发到急性体重后长期缓解的一系列经历 修复。此外，样本恢复的急性体重在入院后将被跟踪6个月 出院，一个高复发风险的时间，纵向检查行为和神经之间的联系 特点和结果。这项研究的发现将有助于确定支持 疾病的持续也有助于缓解，从而明确了复发预防治疗的目标。

Anorexia nervosa (AN) is a serious disorder with a mortality rate among the highest of any psychiatric illness. Central to the morbidity and mortality of AN is a persistent tendency to restrict caloric intake below the body's needs, with a specific tendency to limit calories derived from fat. This perplexing behavior is highly resistant to change, even with a full course of inpatient treatment and weight restoration. Furthermore, restrictive eating patterns are linked to the high rates of relapse after hospital discharge. In order to improve outcomes and long-term remission rates, it is critical to better understand the pathophysiology of illness. This proposal specifically aims to elucidate mechanisms that contribute to the perpetuation of illness and, conversely, to sustained remission. One putative mechanism of persistent maladaptive behavior is habit formation, through which learned behaviors become relatively insensitive to goals. Habit behavior is associated with neural activity in dorsal frontostriatal systems. Here, we will assess habitual and goal-directed behavior across three experiments to provide an in-depth assessment of the behavioral and neural mechanisms that support persistence of illness, as well as remission from illness. This comprehensive battery includes an augmented Two-Step decision task to assess the preponderance of habitual vs goal-directed behavior (modified to improve habit sensitivity), the Avoidance Habit task to assess habit formation in the setting of aversive outcomes, and a Pavlovian Instrumental Transfer task to assess how strongly context cues exacerbate habitual behavior. The task battery will also measure general vs food-specific abnormalities. Our central hypothesis is that habits contribute to the persistence of illness, whereas goal-directed behavior contributes to remission. To examine brain and behavior characteristics associated with short and long-term remission, we leverage our longstanding research unit, which has a successful program for full weight restoration (acute remission), and has a Research Registry that has been in place for more than a decade. We will administer our task battery with fMRI to acutely weight restored inpatients with AN (n=80), individuals in longer-term remission from AN (n=40, recruited from the Research Registry), and healthy comparison women (HC, n=40). We will also invite all eligible patients in the Research Registry (n=397, currently) to complete our task battery online, in order to assess habitual vs goal-directed behavior across a large sample, spanning a range of experiences from relapse to long-term remission after acute weight restoration. In addition, the acutely weight restored AN sample will be followed for 6 months after hospital discharge, a time of high relapse risk, to examine longitudinally the association between behavioral and neural characteristics and outcome. Findings from this study will help determine whether the mechanisms that support persistence of illness also support remission, thereby clarifying targets for relapse prevention treatment.