The stress that started your insomnia is often long gone, so why is the insomnia still here? Today we take the trap apart. Fair warning: you will probably recognize yourself, and that's the useful part.
Sleep science describes insomnia with three P's:
Predisposition. Some of us run a little more wired: lighter sleepers, busier minds, more sensitive stress systems. That's a starting point, not a sentence — plenty of predisposed people sleep fine their whole lives.
Precipitant. The thing that tipped you over: a stressful season, an illness, grief, a schedule upheaval. Bad nights in hard times are completely normal, and for most people sleep returns on its own once the storm passes.
Perpetuation. Sometimes it doesn't return, because during the bad nights you started doing sensible things:
Run each of those through the machinery from last session. Extra time in bed spreads your sleep pressure across more hours, so it sits thinner everywhere. Lie-ins and naps drain the tank and shift the clock. The next night is worse, so you cope harder, and that circle is what keeps insomnia running long after the original stress has gone.
A second loop runs on top of the first, and it's mental. After enough bad nights, the bed itself starts to mean frustration. You're sleepy on the couch at ten and wide awake the moment your head hits the pillow, because your body has learned that lying down is when the struggle starts.
You can't change your predisposition, and the precipitant already happened. But the perpetuating loop, the behaviors and the learned associations, is running right now, which means it can be interrupted right now. That's the part CBT-I attacks, and it's the part keeping you up.
This week your only job is evidence. Five diary mornings, and we can see your personal loop in numbers. Next week, we start cutting.