In anticipation of palatable food, rats can learn to restrict consumption of a less rewarding food type resulting in an increased consumption of the preferred food when it is made available. This construct is known as anticipatory negative contrast (ANC) and can help elucidate the processes that underlie binge-like behavior as well as self-control in rodent motivation models. In the current investigation we aimed to shed light on the ability of distinct predictors of a preferred food choice to generate contrast effects and the motivational processes that underlie this behavior. Using a novel set of rewarding solutions, we directly compared contextual and gustatory ANC predictors in both food restricted and free-fed Sprague-Dawley rats. Our results indicate that, despite being food restricted, rats are selective in their eating behavior and show strong contextually-driven ANC similar to free-fed animals. These differences mirrored changes in palatability for the less preferred solution across the different sessions as measured by lick microstructure analysis. In contrast to previous research, predictive cues in both food restricted and free-fed rats were sufficient for ANC to develop although flavor-driven ANC did not relate to a corresponding change in lick patterning. These differences in the lick microstructure between context- and flavor-driven ANC indicate that the motivational processes underlying ANC generated by the two predictor types are distinct. Moreover, an increase in premature port entries to the unavailable sipper – a second measure of ANC – in all groups reveals a direct influence of response competition on ANC development.

在预期可口的食物时，老鼠可以学会限制对不太有益的食物类型的消费，从而在提供时增加对首选食物的消费。这种结构被称为预期负对比 (ANC)，可以帮助阐明啮齿动物动机模型中的狂欢行为以及自我控制背后的过程。在目前的调查中，我们旨在阐明偏好食物选择的不同预测因子产生对比效应的能力以及这种行为背后的动机过程。使用一组新颖的奖励解决方案，我们直接比较了食物限制和自由喂养的 Sprague-Dawley 大鼠的上下文和味觉 ANC 预测因子。我们的结果表明，尽管受到食物限制，大鼠在进食行为方面具有选择性，并表现出与自由喂养动物相似的强烈情境驱动的 ANC。这些差异反映了通过舔微结构分析测量的不同疗程中较不受欢迎的解决方案的适口性变化。与以前的研究相比，食物限制和自由喂养大鼠的预测线索足以使 ANC 发展，尽管风味驱动的 ANC 与舔模式的相应变化无关。上下文驱动的 ANC 和风味驱动的 ANC 之间的舔微结构的这些差异表明，由两种预测类型生成的 ANC 背后的动机过程是不同的。而且，