There is a cycle you need to break, and a routine you need to stick toNeil Shaw Assistant Editor (Money and Lifestyle)11:35, 09 Jul 2026A professor has explained why people are finding themselves awake at 2am and what actually works to beat it. Michelle Spear, Professor of Anatomy at the University of Bristol, says being alert in the middle of the night is hard-wired into our brains as a survival instinct, but you can change it.‌She said: "Te brain does not simply fall asleep because the body is fatigued. In fact, under stress, exhaustion and sleeplessness often occur together. Part of the reason lies in the biology of survival. The human stress response evolved to deal with immediate physical threats.‌"For most of human history, danger tended to be extreme and short-lived – a predator nearby, an environmental hazard or conflict with another human group. In those moments, the brain’s priority was not rest but survival. When the brain detects threat, a region called the amygdala initiates the body’s classic fight-or-flight response.‌"Stress hormones including adrenaline and cortisol are released. Heart rate increases, breathing quickens and attention sharpens. Energy is diverted away from long-term maintenance tasks towards immediate action. This response is extraordinarily useful – if you are trying to escape a sabre-toothed tiger. It is much less useful when the 'threat' is an overflowing inbox or mounting financial pressure."‌Professor Spear said modern threats 'rarely resolve quickly'. She said: "Emails continue arriving. Work follows us home through smartphones and laptops. Social media creates a constant stream of social comparison and low-level vigilance. Even leisure time has become strangely porous, interrupted by notifications, messages and often the expectation of permanent availability."She said the result is that the parts of the brain responsible for keeping us alert can remain 'partially activated' for long periods.Professor Spear told The Conversation: "This matters because sleep is not simply the absence of wakefulness. Falling asleep requires the brain to actively reduce alertness. A network of arousal centres in the brainstem, hypothalamus and forebrain normally keeps us awake and attentive during the day. To transition into sleep, these systems must quieten down.‌"Under long-term stress, however, the brain can become stuck in a state of hyperarousal. Even when the body is exhausted, the brain continues scanning, anticipating and rehearsing. From an evolutionary perspective, this makes a certain kind of sense. If the environment feels threatening or uncertain, being fully offline may not seem safe."She said physical exhaustion and mental arousal are controlled by overlapping but partly separate systems, adding: "Your muscles may desperately need rest while your brain continues producing stress-driven alertness. The result is the strange mismatch many people know well, a tired body and racing thoughts."‌Prodessor Spear said: "Under normal circumstances, cortisol follows a daily rhythm. Levels rise in the morning to promote wakefulness and gradually decline towards night. Chronic stress can disrupt this pattern, leaving the body activated later into the evening."As well as stress, other factors keep you awake in the middle of the night. Professor Spear said: " Artificial light suppresses melatonin, the hormone that helps regulate sleep timing. Smartphones provide endless cognitive stimulation at exactly the point the brain should be winding down. Doomscrolling combines emotional arousal, uncertainty and novelty – three things human attention systems find almost impossible to ignore."And she explained what could actually help: "Sleep researchers often emphasise that rest and safety are closely linked in the brain. Consistent routines, reduced evening stimulation, exercise, daylight exposure and limiting late-night screen use can all help reinforce the signals that night is a time for recovery rather than alertness. Cognitive behavioural therapy for insomnia has also proved remarkably effective, partly because it targets the cycle of anxiety and sleeplessness itself.Article continues below"Perhaps the most important point is broader. Feeling 'wired but tired' is not evidence that your body has failed to rest properly. Often it is evidence that the brain has become too good at staying alert in a digital world that never really stops."