Key Laboratory of Cognition and Personality (Ministry of Education), Southwest University, Chongqing 400715, China; School of Psychology, Southwest University, Chongqing 400715, China; School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu 611731, China.
Key Laboratory of Cognition and Personality (Ministry of Education), Southwest University, Chongqing 400715, China; School of Psychology, Southwest University, Chongqing 400715, China; Department of Biological Psychology, Vrije Universiteit Brussel (VUB), Brussels, Belgium.
Appetite. 2016 Oct 1;105:477-86. doi: 10.1016/j.appet.2016.05.017. Epub 2016 May 18.
Theory and associated research indicate that people with elevated restrained eating (RE) scores have higher risk for binge eating, future bulimic symptom onset and weight gain. Previous imaging studies have suggested hyper-responsive reward brain area activation in response to food cues contributes to this risk but little is known about associated neural impulse control mechanisms, especially when considering links between depleted cognitive resources related to unsuccessful RE. Towards illuminating this issue, we used a chocolate-specific delayed discounting (DD) task to investigate relations between RE scores, behavior impulsivity, and corresponding neural impulse control correlates in a functional magnetic resonance imaging (fMRI) study of 27 young women. Specifically, participants were required to choose between more immediate, smaller versus delayed, larger hypothetical chocolate rewards following initial consumption of a chocolate. As predicted, RE scores were correlated positively with behavior impulse control levels. More critically, higher RE scores were associated with stronger activation in impulse control region, the dorsal-lateral prefrontal cortex (DLPFC) during the completion of difficult decision trials reflecting higher cognitive demands and resource depletion relative to easy decision trials. Exploratory analyses revealed a positive correlation between RE scores and activity in a reward system hub, the right striatum. Moreover, a positive correlation between left DLPFC and striatum activation was posited to reflect, in part, impulse control region compensation in response to stronger reward signal among women with RE elevations. Findings suggested impulse control lapses may contribute to difficulties in maintaining RE, particularly when cognitive demands are high.
理论和相关研究表明，限制进食（RE）得分较高的人暴食、未来出现贪食症症状和体重增加的风险更高。以前的影像学研究表明，对食物线索的反应过度活跃的奖励大脑区域激活与这种风险有关，但对于相关的神经冲动控制机制知之甚少，尤其是在考虑与不成功的 RE 相关的认知资源消耗有关的联系时。为了阐明这个问题，我们使用了一种特定于巧克力的延迟折扣（DD）任务，在一项针对 27 名年轻女性的功能性磁共振成像（fMRI）研究中，调查了 RE 评分、行为冲动性和相应的神经冲动控制相关性之间的关系。具体来说，参与者需要在最初摄入巧克力后，在即时、较小的巧克力奖励与延迟、较大的巧克力奖励之间做出选择。正如预测的那样，RE 评分与行为冲动控制水平呈正相关。更重要的是，较高的 RE 评分与冲动控制区域的激活呈正相关，即背外侧前额叶皮层（DLPFC），这反映了在困难决策任务中与简单决策任务相比，认知需求更高和资源消耗更大。探索性分析显示，RE 评分与奖励系统中枢右纹状体的活动呈正相关。此外，假设左 DLPFC 和纹状体的激活之间存在正相关，部分反映了在具有 RE 升高的女性中，冲动控制区域在对更强的奖励信号的反应中的补偿。研究结果表明，冲动控制失误可能导致维持 RE 困难，尤其是在认知需求较高时。
