Negative Influence of the hunger state on rule-observance behavior in mice

Abstract

Developing social strategies to share the limited resources equally and maximize the long-term benefits of conflict resolution is critical for appropriate social interactions. During social interactions, making social decisions depend not only on the external environment but also on internal factors such as hunger, thirst, or fatigue. In particular, the hunger state, which is related to food as a physical need, plays a dominant role in social decision-making. However, the consequences of food deprivation on social decision-making are not well understood. We have previously shown that mice in rule-observance behavior are capable of resolving conflict during social decision-making by observing the well-established social strategy based on reward zone allocation. Here, we develop a rule-observance behavior paradigm, in which the hunger state is achieved by applying food restrictions on mice prior to social behavior. We found that the hunger state in mice deteriorated the established social strategy by decreasing the reaction time, implying an increase in impulsivity. In contrast, the hunger state did not affect the reward zone allocation, indicating no effect on spatial memory. This decrease in reaction time led to a significant increase in the percentage of wrong social decisions (violation) and a significant decrease in the amount of reward (payoff equity). Our study proposes that the hunger state exerts a detrimental effect on appropriate social decision-making by decreasing reaction time, increasing violation, and decreasing payoff equity in rule-observance behavior.