You are exhausted. You close your eyes. And instead of sleep, your brain serves up a highlight reel of your worst moments from the past decade. This is not a moral failure. It is a biological mismatch between ancient wiring and modern life.

Your brain evolved to stay alert in the presence of threats. In the savanna, that threat was a predator. Today, that threat is an email from your boss, a text from an ex, or a news alert about the economy. Your brain cannot tell the difference. The same cortisol and adrenaline that helped your ancestors outrun lions now spike because you scrolled social media before bed.

Other common culprits include inconsistent sleep schedules that confuse your circadian rhythm, caffeine consumed even six hours before bedtime, alcohol that fragments REM sleep, and blue light that suppresses melatonin production. Sleep hygiene is not a trend. It is the science of tricking your ancient brain into relaxing in a world it was never designed for.

Turn down the lights, put on your headphones, and press play because struggling to sleep is not a character flaw. It is a design flaw. And design flaws can be fixed.