Tired but wired

Tired but wired is the state where the body has clearly finished for the day and the mind has clearly not. Sleep pressure is high — you were nodding on the sofa an hour ago — and the moment the light goes off, something switches on. Not anxiety exactly. An audit.

Sleep researchers have a less evocative name for it: hyperarousal. The finding behind the word, reviewed by Riemann's group and by Bonnet and Arand in 2010, is that people with persistent insomnia are not under-tired. They are over-activated — measurably, around the clock: higher heart rate, higher cortisol, more fast brain activity, even during the day. The body is not failing to switch off at night. It never fully switched off.

Harvey's cognitive model of insomnia, from 2002, is the best description of the sequence most people would recognise if they watched themselves:

1. The day's leftover arrives. A conversation, a worry, the thing you did not say. The pillow is the first quiet the mind has had, so it takes the job.
2. Monitoring begins. Am I asleep yet. How long has it been. What time is it now. The checking is itself arousal, so it produces the thing it is checking for.
3. The maths starts. If I fall asleep now I get five hours. The maths is never reassuring, and it is done wide awake.
4. Safety behaviours. The phone. The other room. The extra hour in bed in the morning that shifts the clock and makes the next night worse.

Two features of the loop matter for what follows. It has a subject — the thing from step one — and it has a trigger: the night is bad because the day was.

Ask what the subject was and the answer, very often, is a person. More specifically, an unfinished exchange with a person: the argument you went around rather than had, the message you drafted and did not send, the silence that went on all evening and was never explained.

There is a reason this is the reliable one. An avoided conflict has nowhere to go. The thing that was not said in the room does not evaporate; it waits for the first quiet, and then the mind holds the hearing you avoided — with you as both sides, cross-examining and defending, at length, for no verdict. The sleep score is not describing a sleep problem. It is describing a conversation that keeps office hours after midnight.

The research has a name for the tendency here too. Drake's group showed that people differ in sleep reactivity — how much a given stress disturbs a given person's sleep — and that high reactivity is a stable trait that predicts who develops chronic insomnia after a hard patch. Some people's sleep simply reads the day more closely. Those are the people for whom a fight at 8pm and a bad night at 2am are not two problems.

That is the Conflict Style test's territory: whether you say the thing, go around it, or go still. Put next to the Sleep Quality test, a high avoidance score and a poor night make a pattern — one we name, on the result page, as sleep after the fight. The entry on conflict and repair is the longer road into why the unsaid thing is the expensive one.

The loop is one system, seen from two ends. The night does not restore you, so the day runs on adrenaline; the adrenaline does not switch off at night, so the mind runs instead of sleeping. The trap is treating one end alone. Sleep hygiene — dark room, no screens, no caffeine — does very little while the mind is loud, and no amount of thinking quiets a mind that is exhausted. People who have done everything on the hygiene list and still lie awake have usually reached this paragraph already.

Hyperarousal is treatable, and not by us. The clinical answer to persistent insomnia is CBT-I — cognitive behavioural therapy for insomnia — which works on exactly the monitoring, the maths and the safety behaviours above, and which outperforms medication over the long term in trial after trial. If the nights have been bad for weeks, that is where the road goes, and a doctor is the way onto it. This page is a map, not a treatment.

The tendency is measurable. Sleep reactivity is a trait; where you sit on it is worth knowing, because it tells you whether protecting your evenings is a nicety or a necessity.

Three tests read the loop from its three ends. The Sleep Quality test reads the night itself — latency, continuity, what the morning is like. The Overthinking test reads how loud the mind gets, and the entry on rumination explains why it is loudest at the pillow. The Conflict Style test reads whether the subject of the loop is a conversation you did not have. Together they name the pattern — tired, and wired — rather than the symptom.

Then two things, neither of them a cure:

• Move the thinking earlier. Twenty minutes, on paper, at a fixed time in the afternoon, for every subject that would otherwise wait for the pillow. The mind lets go of a topic it knows has an appointment.
• Finish the conversation in daylight. If the subject is a person, the smallest true sentence, said to them, tomorrow, does more for the night than anything done in it.

The first sign that any of this is working is not sleeping through. It is a night where the audit starts up, and there is nothing new on the list.