HCRT and insomnia: In AUD, sleep pathology aligns with the addiction cycle: during intoxication, faster sleep onset but poorer sleep; during withdrawal, SWS loss and only partial REM recovery; during protracted abstinence, persistent insomnia, reduced delta power, and heightened REM—changes linked to adaptations in GABA/glutamate, dopamine, stress systems (corticotropin-releasing factor, norepinephrine, orexin), and circadian regulation [36,267].