Sleep transcends limited knowledge to support logical reward-related decisions in a novel task in male mice

Sleep is essential for strengthening memory and consolidation. Emerging evidence supports its role in cognitive processes such as rule abstraction and inference. However, how sleep influences logical nongambling probabilistic decision-making has yet to be discovered. We developed a reward-based logical decision task that requires rule use and allows scope for reasoning. The mice were able to discriminate between two contexts with different outcomes. This behavior paradigm teaches mice to make free choices between an option to obtain a high-value probabilistic reward in specific entries and a guaranteed safe, low-value option. This knowledge was acquired through six forced entries to each side in training sessions, and they were then tested on subsequent days. As a hidden rule, they may extend their knowledge during these testing sessions by being allowed to take extra entries. We found that extended sleep deprivation disrupted their logical decisions. Sleep-deprived mice were unable to maintain their previous logical performance, resulting in a significant reduction in the rewards they earned. Rule switching in an updated version of the task eliminated gambling-like behavioral dependence in this novel task. These results suggest that adequate sleep is necessary for applying learned knowledge and engaging in complex cognitive functions, such as reasoning.