Reward activity in satiated overweight women is decreased during unbiased viewing but increased when imagining taste: an event-related fMRI study
Reward activity in satiated overweight women is decreased during unbiased viewing but increased when imagining taste: an event-related fMRI study
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DOI：
10.1038/ijo.2011.213
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发表时间：
2012-05-01
影响因子：
4.9
通讯作者：
Jansen, A.
中科院分区：
文献类型：
--
作者：
Frankort, A.;Roefs, A.;Jansen, A.
目的：这项功能性磁共振成像（fMRI）研究的目的是调查超重和健康体重的参与者在没有事先指导的情况下观看图片（称为无偏见观看）与想象所显示图片的味道（称为味觉想象）时，对高热量可口食物图片的反应中与奖励相关的大脑活动。我们预测，超重参与者的大脑奖励区域的神经激活会比健康体重的参与者更大，并且在无偏见的观看过程中，组间的这种差异将最强。方法：使用 fMRI 测量 14 名超重（平均体重指数（BMI）：29.8 kg m(-2)）和 15 名健康体重（平均 BMI：21.1 kg m(-2)）参与者的神经激活，这些参与者对可口和不可口的食物感到满意高热量和低热量食物图片，在两种条件下以与事件相关的设计呈现：公正观看（无事先说明）与味觉想象。结果：在呈现高热量可口食物刺激期间，在涉及食物奖励处理的 14 个大脑区域中发现了一组 x 条件相互作用。在味觉想象条件下，超重参与者这些区域的神经激活程度高于健康体重参与者。与我们的预期相反，在公正的观看过程中观察到了相反的模式：与健康体重的参与者相比，超重参与者奖励区域的激活减少了。在除左侧杏仁核之外的所有大脑奖励区域中，x组条件交互作用特定于高热量可口食物刺激。结论：与对照组相比，超重参与者在想象味道时的奖励活动更大，这可能代表高热量可口食物引起的奖励反应增加。在公正的观看过程中，与健康体重的参与者相比，超重参与者的奖励激活减少可能反映了对高热量可口食物刺激的回避。总而言之，这种激活模式可能反映了超重群体在渴望（在味觉想象条件下）和避免（在公正的观看条件下）高热量可口食物刺激之间的矛盾心理。国际肥胖杂志 (2012) 36, 627-637； doi：10.1038/ijo.2011.213； 2011 年 11 月 8 日在线发布
Objective: The aim of this functional magnetic resonance imaging (fMRI) study was to investigate reward-related brain activity in satiated overweight and healthy-weight participants in response to high-calorie palatable food pictures, when viewing the pictures without prior instructions (called unbiased viewing) versus imagining the taste of the shown pictures (called taste imagination). We predicted that neural activation in brain reward regions would be greater in overweight participants than in healthy-weight ones and that this difference between groups would be strongest during unbiased viewing.Method: Neural activation was measured using fMRI in 14 overweight (mean body mass index (BMI): 29.8 kg m(-2)) and 15 healthy-weight (mean BMI: 21.1 kg m(-2)) participants who were satiated, in response to palatable and unpalatable high-calorie and low-calorie food pictures, presented in an event-related design during two conditions: unbiased viewing (no prior instructions) versus taste imagination.Results: A group x condition interaction was found in 14 brain regions involved in food reward processing during the presentation of high-calorie palatable food stimuli. During the taste imagination condition, neural activation in these regions was greater in the overweight participants than in the healthy-weight ones. Contrary to our expectations, the opposite pattern was observed during unbiased viewing: activation in reward regions in the overweight participants was reduced compared with the healthy-weight ones. In all brain reward regions except for the left amygdala, the group x condition interaction was specific to high-calorie palatable food stimuli.Conclusion: Greater reward activity in the overweight participants compared with the control group when imagining taste may represent an increased reward response induced by high-calorie palatable food. During unbiased viewing, reduced reward activation in the overweight participants compared with those with a healthy weight may reflect avoidance of high-calorie palatable food stimuli. Taken together, this pattern of activation may reflect ambivalence in the overweight group between desire for (in the taste imagination condition) and avoidance of (in the unbiased viewing condition) high-calorie palatable food stimuli. International Journal of Obesity (2012) 36, 627-637; doi:10.1038/ijo.2011.213; published online 8 November 2011