Sleeping too much, struggling to wake up, or feeling exhausted despite spending enough time in bed are common experiences among people with depression . However, new research suggests that, for some individuals, these symptoms may reflect more than ordinary sleep disturbances. They may be associated with disruptions to the body’s internal biological clock, a system that regulates sleep, wakefulness, hormones and other daily physiological processes that affect mental health.

A study published in The British Journal of Psychiatry in October 2026 has proposed a distinct pattern of depression known as “circadian depression.” Researchers found that approximately one in four participants with severe, recurrent or persistent depression displayed characteristics associated with this pattern.…