Sensation, Perception & Behaviour, Unilever R&D Vlaardingen, AC Vlaardingen, The Netherlands.
Appetite. 2011 Aug;57(1):45-9. doi: 10.1016/j.appet.2011.03.007. Epub 2011 Apr 2.
This study investigated the development of conditioned preferences for foods varying in energy content in human adults in a laboratory setting. In a within-subjects design, 44 participants consumed high and low energy yoghurt drinks (255 kcal and 57 kcal per 200 ml serving, respectively) first thing in the morning following 8 h of fasting, every day for two weeks, with 5 exposures to each yoghurt drink on alternate days. The high and low energy yoghurt drinks were paired with two coloured labels (blue or pink), with the pairings fully counter-balanced. Every day of the third (test) week, participants were given a free choice of either consuming the pink or the blue labelled yoghurt drink. Participants chose the high energy drink significantly more often over the low energy drink, suggesting a conditioned preference for a delayed (energy) reward. These findings provide further evidence for energy based learning in human adults. This study also provides a new approach to the conditioning paradigm (cueing energy via a coloured label instead of flavour) and includes a new and important measure in this research area (preference instead of liking).
本研究在实验室环境中调查了人类成年人对能量含量不同的食物的条件性偏好的发展。采用被试内设计，44 名参与者在禁食 8 小时后，每天早上第一件事就分别饮用高能量和低能量的酸奶饮料（每份 200 毫升分别含有 255 卡路里和 57 卡路里），两种酸奶饮料每隔一天各有 5 次摄入，共持续两周。高能量和低能量的酸奶饮料分别与两个彩色标签（蓝色或粉色）配对，配对完全平衡。在第三（测试）周的每一天，参与者都可以自由选择饮用粉色或蓝色标签的酸奶饮料。参与者选择高能量饮料的次数明显多于低能量饮料，这表明他们对延迟（能量）奖励产生了条件性偏好。这些发现为人类成年人的基于能量的学习提供了进一步的证据。本研究还提供了一种新的条件作用范式（通过彩色标签提示能量，而不是口味），并在该研究领域提出了一个新的重要衡量标准（偏好而不是喜欢）。
