As delirium is associated with neuroinflammation in the brain,[49] it is speculated that delirium‐induced disruption of circadian rhythms is, at least in part, attributed to neuroinflammation as the inflammation regulators (e.g., NF‐κB) and inflammatory cytokines (e.g., TNFα and IL‐1β) can regulate expression of core clock genes such as Rev‐erbα, Pers, and Dbp. The gene discussed is CLOCK; the disease is delirium.