Department of Psychiatry,University of Oxford, Oxford, UK.
Am J Clin Nutr. 2013 Mar;97(3):463-70. doi: 10.3945/ajcn.112.046011. Epub 2013 Jan 30.
Recent frameworks for understanding food rewards recognize the role of separable affective and motivational processes (liking and wanting) in driving human eating behavior. Separate assessments of liking and wanting may aid in understanding the complex eating-related behaviors seen in anorexia nervosa (AN).
The aim of this study was to examine separately liking and wanting for foods of different energy densities in women at different stages of AN and in healthy volunteers at both an implicit and an explicit level.
Explicit liking and wanting responses to high- and low-calorie foods were derived from analog ratings, whereas an implicit "wanting" measure was identified by using reaction time in a forced-choice procedure. Explicit and implicit processes were compared across 3 groups of AN participants (current AN, weight-restored AN, and recovered AN) and healthy volunteers.
Currently underweight AN participants explicitly wanted high-calorie foods less than did the other groups. Both current and weight-restored AN groups demonstrated significantly less implicit "wanting" for high-calorie foods and more implicit "wanting" for low-calorie foods-an inverted pattern to never-ill participants.
The aberrant responses to food that characterize AN may be driven more by altered motivational salience ("wanting") than by explicit liking responses. This pattern of aberrant food reward appears to be independent of weight status. Examining the processes that motivate approach or avoidance of low- and high-calorie foods in AN may aid the development of targeted strategies to augment existing interventions.
理解食物奖赏的最近框架认识到可分离的情感和动机过程（喜欢和想要）在驱动人类进食行为中的作用。对喜欢和想要的单独评估可能有助于理解神经性厌食症（AN）中看到的复杂与进食相关的行为。
本研究的目的是分别检查处于不同 AN 阶段的女性和健康志愿者在潜意识和显意识层面上对不同能量密度的食物的喜欢和想要。
通过模拟评分得出高卡路里和低卡路里食物的显式喜欢和想要反应，而通过强制选择程序中的反应时间来确定隐含的“想要”测量。在 3 组 AN 参与者（当前 AN、体重恢复的 AN 和恢复的 AN）和健康志愿者之间比较显式和隐式过程。
目前体重不足的 AN 参与者明显比其他组更不想要高热量食物。当前和体重恢复的 AN 组对高热量食物的隐性“想要”明显减少，而对低热量食物的隐性“想要”明显增加——与从未患病的参与者相反。
AN 特征性的食物反应异常可能更多地是由改变的动机显著性（“想要”）驱动，而不是显式喜欢反应。这种异常的食物奖励模式似乎独立于体重状况。检查激励接近或回避低热量和高热量食物的过程可能有助于制定针对现有干预措施的靶向策略。
