Value-based decision making in common marmoset

虽然如果动物感到饥饿和口渴，消耗品奖励的价值就会增加，但饱腹感如何影响消耗品的偏好，从而如何驱动选择行为，目前还不清楚。为了解决这个问题，我研究了六只绒猴(Callithrix Jacchus)对消耗品奖励的选择行为。我测量了每只猴子在不同饥饿程度下对食物的选择和偏好。每只猴子在满足的条件下经常表现出随机选择。然而，当他们感到饥饿时，他们的选择随机性急剧下降。此外，在不同的饱腹感水平之间，每种食物的偏好似乎是稳定的。这些证据表明，不同饱腹度之间的偏好并不是不一致的，但猴子在变得更饿的时候表现得不那么随机。

While the value of consumable rewards increase if animals get hungry and thirsty, it is still unclear how the satiety state affect the preference of consumable goods, and hence how choice behaviors are driven. To address this issue, I examine the choice behavior of six marmoset monkeys (Callithrix jacchus) for consumable rewards. I measured their choices and preferences of foods in each monkey in different hunger levels. Each monkey showed stochastic choices in the sated condition frequently. However, the choice stochasticity dramatically decreased when they were hungry. In addition, preferences of each food items appeared to be stable between different satiety levels. These evidences suggested that preferences are not inconsistent among different satiety level, but monkeys behave less stochastic as they become hungrier.