 chronic stress can lead to sleep disruption and depression due to changes in the brain's melatonin levels. A recent study found that mice experiencing chronic stress had lower levels of melatonin, which caused them to have difficulty falling asleep and staying asleep. Additionally, the study discovered that these mice had alterations in their circadian rhythms and gene expression related to melatonin receptors. This suggests that chronic stress could be linked to sleep disruptions and depression through its effects on melatonin levels. This article was authored by Tian Jixia, Ji Wang, Su Weijin, and others.