Kekic Maria, Bartholdy Savani, Cheng Jiumu, McClelland Jessica, Boysen Elena, Musiat Peter, O'Daly Owen G, Campbell Iain C, Schmidt Ulrike
Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, United Kingdom.
Int J Eat Disord. 2016 Dec;49(12):1077-1081. doi: 10.1002/eat.22571. Epub 2016 Jun 15.
There is evidence that people with eating disorders display altered intertemporal choice behavior (the degree of preference for immediate rewards over delayed rewards). Compared to healthy controls (HC), individuals with anorexia nervosa and binge-eating disorder show decreased and increased rates of temporal discounting (TD; the devaluation of delayed rewards), respectively. This is the first study to investigate TD in people with bulimia nervosa (BN).
Thirty-nine individuals with BN (2 men) and 53 HC (9 men) completed a hypothetical monetary TD task. Over 80 binary choices, participants chose whether they would prefer to receive a smaller amount of money available immediately or a larger amount available in 3 months. Self-reported ability to delay gratification (the behavioral opposite of TD) was also measured.
Individuals with BN showed greater TD (i.e., a preference for smaller-sooner rewards) and a decreased self-reported capacity to delay gratification relative to HC. Experimental groups did not differ in age, gender ratio, or BMI.
Increased rates of TD may contribute to some of the core symptoms of BN that appear to involve making choices between immediate and delayed rewards (i.e., binge-eating and compensatory behaviors). Altered intertemporal choice behavior could therefore be a relevant target for intervention in this patient group. © 2016 Wiley Periodicals, Inc. (Int J Eat Disord 2016; 49:1077-1081).
有证据表明，饮食失调者表现出跨期选择行为改变（即对即时奖励相对于延迟奖励的偏好程度）。与健康对照组（HC）相比，神经性厌食症和暴饮暴食症患者的时间折扣率（TD；延迟奖励的贬值）分别降低和升高。这是第一项调查神经性贪食症（BN）患者时间折扣情况的研究。
39名BN患者（2名男性）和53名HC（9名男性）完成了一项假设性货币时间折扣任务。在80多个二元选择中，参与者选择他们是更愿意立即获得一笔较小金额的钱，还是三个月后获得一笔较大金额的钱。还测量了自我报告的延迟满足能力（TD的行为相反情况）。
与HC相比，BN患者表现出更高的时间折扣率（即偏好更小更快的奖励），且自我报告的延迟满足能力降低。实验组在年龄、性别比例或体重指数方面没有差异。
时间折扣率增加可能导致BN的一些核心症状，这些症状似乎涉及在即时奖励和延迟奖励之间做出选择（即暴饮暴食和代偿行为）。因此，跨期选择行为改变可能是该患者群体干预的一个相关靶点。©2016威利期刊公司（《国际进食障碍杂志》2016年；49:1077 - 1081）
