Radboud University, Donders Institute for Brain, Cognition, and Behavior, Nijmegen, Netherlands.
Division of Human Nutrition and Health, Wageningen University, Wageningen, Netherlands.
Am J Clin Nutr. 2020 May 1;111(5):950-961. doi: 10.1093/ajcn/nqaa032.
In the current obesogenic environment we often eat while electronic devices, such as smart phones, computers, or the television, distract us. Such "distracted eating" is associated with increased food intake and overweight. However, the underlying neurocognitive mechanisms of this phenomenon are unknown.
Our aim was to elucidate these mechanisms by investigating whether distraction attenuates processing in the primary and secondary taste cortices, located in the insula and orbitofrontal cortex (OFC), respectively.
Forty-one healthy, normal-weight participants received fixed amounts of higher- and lower-sweetness isocaloric chocolate milk while performing a high- or low-distracting detection task during fMRI in 2 test sessions. Subsequently, we measured ad libitum food intake.
As expected, a primary taste cortex region in the right insula responded more to the sweeter drink (P < 0.001, uncorrected). Distraction did not affect this insular sweetness response across the group, but did weaken sweetness-related connectivity of this region to a secondary taste region in the right OFC (P-family-wise error, cluster, small-volume corrected = 0.020). Moreover, individual differences in distraction-related attenuation of taste activation in the insula predicted increased subsequent ad libitum food intake after distraction (r = 0.36).
These results reveal a mechanism explaining how distraction during consumption attenuates neural taste processing. Moreover, our study shows that such distraction-induced decreases in neural taste processing contribute to individual differences in the susceptibility for overeating. Thus, being mindful about the taste of food during consumption could perhaps be part of successful prevention and treatment of overweight and obesity, which should be further tested in these target groups. This study was preregistered at the Open Science Framework as https://bit.ly/31RtDHZ.
在当前致肥胖环境中，我们经常边吃边看智能手机、电脑或电视等电子设备，即“分心进食”，这种进食方式与食物摄入量增加和超重有关。然而，这种现象的潜在神经认知机制尚不清楚。
我们旨在通过研究分心是否会减弱位于脑岛和眶额皮质（OFC）的初级和次级味觉皮质的处理来阐明这些机制。
41 名健康、体重正常的参与者在两次 fMRI 测试中分别接受高、低甜度等热量巧克力牛奶，同时完成高、低干扰探测任务。随后，我们测量了自由进食量。
正如预期的那样，右侧脑岛的一个初级味觉皮质区域对更甜的饮料反应更强烈（P < 0.001，未校正）。分心并没有改变整个组的这种岛叶甜味反应，但确实减弱了该区域与右侧 OFC 中一个次级味觉区域的甜味相关性连接（P 家族错误、簇、小体积校正=0.020）。此外，分心导致的岛叶味觉激活减弱与随后分心后的自由进食量增加之间存在个体差异（r=0.36）。
这些结果揭示了一种解释分心如何在进食过程中减弱神经味觉处理的机制。此外，我们的研究表明，这种分心引起的味觉处理减少可能导致个体对暴饮暴食的易感性存在差异。因此，在进食过程中注意食物的味道，或许可以成为成功预防和治疗超重和肥胖的一部分，这应该在这些目标群体中进一步测试。本研究已在开放科学框架（Open Science Framework）上预先注册，网址为 https://bit.ly/31RtDHZ。
