Insomnia

A smoke detector stuck on high alert

Your brain's sleep system is like a home security system with a motion detector (amygdala/alarm center), a control panel (prefrontal cortex/brake), a power switch (ventrolateral preoptic nucleus/sleep switch), and a battery charger (adenosine buildup/sleep drive). Normally, during the day the system runs on high sensitivity to catch threats, and at night the control panel remotely powers everything down so the battery can recharge undisturbed. But chronic stress leaves the motion detector hypersensitive and the control panel exhausted from overuse, so it cannot flip the power switch anymore. The system stays in 'armed' mode even when you try to sleep, draining the battery faster. Your compensations—like napping or using sleeping pills—are like using a jumper cable instead of fixing the broken switch; they might start the engine temporarily, but the underlying problem gets worse. Only retraining the system (CBT-I) recalibrates the motion detector's sensitivity and rebuilds the control panel's strength so the power switch works again.