“Close your eyes and breathe normally,” the therapist said. Here I was – a doctor trained in the western school of rational inquiry, empirical evidence and, dare I say it, snobbish cynicism – being hypnotised. But I’d lived with irritable bowel syndrome (IBS) for as long as I could remember, with abdominal cramps bringing regular discomfort and occasional agony. Medications and dietary changes had done absolutely nothing. I was aware of the growing evidence for hypnotherapy’s effectiveness for various painful conditions, but when I sat down on the hypnotherapist’s couch and closed my eyes for the first time, it felt more like a prayer of desperation than a reasoned treatment decision. Through words of suggestion, my hypnotherapist gently guided my attention across my body for about 10 minutes. I felt as though I was selectively shining a torch on sensations I never pay any attention to: the heaviness of my feet, the sound of my breathing. He then pulled my attention down to my sore, cramping abdomen and used imagery to change the way I saw my pain. “Picture your intestines as though they are a river,” he said. “Now, it might seem like a fast stream of rocky rapids, but instead imagine it as the gentle Thames, with languidly moving punts gently drifting downstream.” Over the following weeks, I could still feel painful sensations during flare-ups, but the pleasant imagery I was now associating with IBS was beginning to change my experience of it. It was as though I could take a step back and look at my own pain as an observer. My hypnotherapist treats many clients for phobias, and I wondered whether a similar process was at work with my pain. I used to visualise it like a threatening-looking spider. But now, instead of fleeing into another room or trying to thwack it with a newspaper, I could gently pick it up and rehome it in the garden. After a few weeks of practising self-hypnosis, the pain began to wane, and after a couple of months it completely stopped. To this day, no IBS symptoms have returned. This experience began to rock the foundation of my belief that pain is an accurate measure of injury. On the surface, this seems to make sense, but if we look more closely it’s clear that the relationship between pain and injury is not at all linear. Severe tissue damage can occur without pain: we have all heard stories of soldiers in the heat of battle completely anaesthetised to their missing limb. Pain can also occur without any injury – even without any tissue, as seen in the surprisingly common phenomenon of phantom limb pain in amputees. And all of us have some sense that the same injury is more painful when your mood is low, or if the harm is caused by another person in a threatening situation. If pain were a reflex, a simple signalling system from the body to the brain, then we should always and only feel pain when our tissue is damaged, with the pain directly proportional to the extent of injury. Pain only begins to make sense when you understand a fundamental, revolutionary truth that modern pain science is revealing: pain is a protector, not a detector. Pain is an executive decision made by our brain outside our conscious control, to tell our conscious mind that we are in danger and to motivate us to protect our body. Where another more important survival priority trumps this – take the soldier on the battlefield fighting for their life – the brain might decide not to create pain at all, or to delay it to a later time. In most cases of short-term – or “acute” – pain, hurt is usually an accurate indicator of harm. You shut your laptop on your thumb and it hurts; you slam it in a car door and it hurts more. But the link between hurt and harm begins to wane the longer pain persists. At least a fifth of most populations today live with persistent – also called chronic – pain. Persistent pain ruins millions of lives, but it was only recognised as a disease in its own right in 2019 and is often glossed over at medical schools. In many cases of persistent pain the initial injury has long since healed. Through a mechanism called central sensitisation, the brain has become overprotective and pain becomes “wired” in. I am not for one minute saying that persistent pain is “all in your head” – an issue of incorrect thoughts. Rather it is neurological, as real as epilepsy. But how could this help us deal with pain? It comes down to a simple formula: to rewire your brain out of long-term pain, you need to persistently provide it with evidence of safety and reduce evidence of threat. It’s a matter of gradually calming down an overprotective brain, letting it know that the body is safe. To my surprise, I found hypnotherapy a useful vehicle for this, but there are many other evidence-based ways to make the brain feel safer in its body. One example is movement – from exercise to knitting – that provides your brain with data that your body is strong and safe. And new technology could also help us find our way out of pain. A virtual reality (VR) interactive snowscape helps burns sufferers manage their notoriously painful wound care. A team in France has combined one of the world’s oldest therapies – hypnosis – with one of our newest technologies – VR – to give children recovering from surgery the opportunity to experience hypnotherapy in a relaxing VR environment of their choice, from a tropical beach to a mountaintop. Children given a 20-minute “hypnoVR” session within 72 hours of surgery required half the amount of post-operative morphine compared with those who received standard care. It will be fascinating to see whether VR can also help the brain rewire itself out of persistent pain. Still, most people – including doctors – have an outdated idea of what pain is and why it exists, although public outreach is slowly changing that. Understanding how pain really works is the first step to truly managing it. Monty Lyman is a doctor and the author of The Painful Truth