Ouch! Solving the riddle of pain

Deep in the basement of Oxford’s Institute of Biomedical Engineering, I am sitting in a pain laboratory trying to describe a series of small but exquisitely sharp electrical shocks emanating from an electrode attached to my index finger. It is proving to be something of a challenge. “Yeah, no, that’s really, er, unpleasant,” I offer, inarticulately, as the electric shocks slowly ramp up, their intensity putting me in mind of an excruciating jellyfish sting last summer.

“Ow, that really hurts,” I manage. Up goes the volume. “And this?” Language escapes me and I emit a small reflexive cry instead. Dr Ben Seymour, a professor of clinical neuroscience and honorary consultant neurologist at Oxford University who has designed these tests, looks rather pleased. We are working our way briskly through a varied menu of different aches and pains, some heated, some chilled. The electric shock to the finger is the equivalent of an injury signal, a short sharp warning pain to alert us to danger. “It’s the ‘ow’ one,” explains Seymour. “I call it the wasp as it has a kind of angriness to it.”

Next up is the Velcro strap around my arm that inflates slowly, a little like measuring for blood pressure but more extreme and much tighter. Shooting pains ripple through my arm, but I also feel heat, soreness and a slow, dull ache that lasts after the strap is removed. “So this one is useful because it spreads and you get different sensations to it, more akin to chronic pain.” There is also a probe pressed to the skin that can be freezing or boiling. “That’s pretty unpleasant… We can control it very precisely. Cold pain is more the kind that gnaws at the bones. It’s really horrible so, yes, that’s a good one, too.”

Pain is still one of science’s most elusive mysteries, perhaps because it is so notoriously difficult to share and communicate In her essay On Being Ill, Virginia Woolf noted, “…there is the poverty of language. English which can express the thoughts of Hamlet and the tragedy of Lear has no words for the shiver and the headache… let a sufferer try to describe a pain in his head to a doctor and language at once runs dry.” Seymour believes this difficulty arises because pain originates from such an ancient area of the brain. “It kind of has a primeval sense to it. That’s what probably makes it so difficult to treat, too.”

So how, exactly, would he describe pain? He thinks for a moment. “Well… it’s part sense, part emotion, part feeling, part qualia. It’s also fundamental to the notion of who we are. Nothing else ties you to your own body, to the present moment. I’d argue that pain is the requirement that precipitated the evolution of movement. Even an amoeba knows the most important thing is not to get squashed.” Like amoebae, humans spend pretty much every waking moment trying not to get squashed or hurt either.

Seymour’s interest began when he was a medical student at Manchester and started to notice how dismissive other colleagues were about pain, as if it was an annoying byproduct of medicine, rather than a symptom worthy of more attention. “No one was taking it seriously. I thought of it as one of the hardest problems to solve in medicine. I wanted to understand and figure it out.”

Now in his own pain lab at Oxford, he wants to understand more about the difference between pain as a warning signal and what happens when it tips over into another state – chronic pain – defined as lasting longer than an expected period of recovery. In the trial he’s designing, respondents will be playing an immersive virtual reality game and today I’m being the guinea pig. Kitted out with a VR headset and controls in each hand, I sway slightly, responding to the wraparound images in front of my eyes. Wandering through a vivid jungle setting, I push through palm trees, bending down to pick up prickly pineapples. Each one registers as a small electric shock via my electrode. Once it’s up and running, respondents will be wired up to an EEG, so researchers can interpret any spike in brain activity on screen.

Just down the corridor, I meet Seymour’s colleague, Tim Denison, professor of engineering science at Oxford University, who is working on deep brain stimulation. Aimed at stroke sufferers, they plan to embed a small device deep in the brain that can be measured and controlled remotely. There are similar devices out there for Parkinson’s disease, and it could work for cluster headaches, too. Is this the future of pain control, where patients can monitor their own brain activity? “I do think that in the course of 50 years, neural technology like this will become much more integrated with human experience,” says Denison. And maybe a safer alternative to medication. “We want to design something where users can actually be in control.”

My own extended brush with pain came in the form of endless attacks of cystitis, a common acute urinary tract infection, and a poorly understood condition that causes untold misery for thousands of women each year. I felt dismissed by GPs who were unable to offer anything more than yet another stick to pee on and repeat prescriptions of antibiotics. After years of suffering, one male registrar suggested cranberry juice and wearing cotton pants. I wanted to scream at him, but I cried instead.

In his research Rob Boddice, historian and author of Knowing Pain: A History of Sensation, Emotion, and Experience observed that: “Women through the ages were thought by male intellectuals to be overwhelmed with passions and emotions by status of their biology. There is a spectre still lurking in attitudes towards clinical presentation of pain. Whether it’s gendered, raced, age-based or classed, there’s an idealised script for presentation of pain in clinic.” In a new study assessing thousands of hospital patients, researchers found that healthcare providers were less likely to offer women pain relief medication than men, or even to record their pain score. Researchers were left to conclude that beliefs around pain exaggeration in women was one reason for this marked gender disparity.

In my own case, it took years but finally my symptoms were taken seriously. After endless referrals, I was back at my local surgery yet again, but this time, thankfully, my GP was too busy to see me and I saw a medical student on work experience. He suggested my condition could be viewed from an entirely different angle and told me about the pain management centre at Guy’s and St Thomas’ hospital, in particular one of the consultant urologists who had practised there.

Once I did get a referral, just as Woolf described, I found myself stuck for words, but I did manage to describe a sensation of crushed glass every time I peed. That seemed to do the trick. After another investigation, I was prescribed a low dose of amitriptyline. This small blue pill is usually used as an antidepressant but, at a far lower dosage, it can help prevent migraines and pain that has lasted a long time. At only 10mg a day, it won’t affect your mood, but it can change the way your nerves receive pain signals. Within weeks my symptoms completely disappeared. In my case, it felt like a miracle. Or was it just common sense? Treating the pain first meant that the cycle of inflammation and infection disappeared as a consequence. Either way, I haven’t touched an antibiotic in over six years.

Once the pain left me, I became interested in its history and I began to think about its possibilities in a fictional setting. The plot for my psychological thriller finally fell into place. It’s about a neuroscientist who works at a mysterious pain laboratory, and his wife who was unable to feel pain but enjoyed inflicting it. Neuroscience, medicine, philosophy, gender and control, all these offered great dramatic potential viewed through the prism of pain.

For centuries, physical suffering was viewed as a penance for sin. Ancient cultures placed their faith largely in magic and ritual; sacrificial animals and scapegoats would be sent out in the hope of driving pain into the wilderness. In the 17th century, early modern thinkers such as René Descartes, philosopher and mathematician, were among the first to consider pain in a different way.

Descartes theorised that pain originated in the brain, a revolutionary idea suggesting physical suffering wasn’t inflicted by an omnipotent external force and raising the radical possibility of individual agency: if pain was created internally, surely it was within our own power to find a cure.

So here we are, centuries later, still searching for that holy grail. According to recent figures, the yearly economic cost associated with chronic pain in the US is around $600bn. “A lot of that is the indirect burden of time off, lost productivity and care demands, as opposed to treatments,” says Seymour. “The worldwide figure is closer to $1trn. So even if you can make a tiny impact on that, you’re saving money.”

But any sort of lasting impact depends on a reliable measurement of pain. As Boddice says: “People have been trying to find an objective measure of pain for 400 years and it is not forthcoming.” In the 1950s, Canadian psychologist Dr Ronald Melzack began to classify the words patients used most often which evolved to become the gold standard McGill Pain Questionnaire, offering patients around 78 descriptions including “drilling”, “lacerating” and “searing”. A simple 0-10 numerical scale is more commonly used these days. Boddice remains sceptical. ‘The McGill terms didn’t come from a patient perspective and it’s amazing how different that questionnaire becomes in Kuwait or Finland or Italy.”

Seymour and his team are only too aware of these language limitations and have set up a project with artist Marysa Dowling, inviting sufferers to express their pain through art and writing. “I’m not an artist but I wanted to be able to describe my pain through photography,” says Clare, who has secondary breast cancer. “I can see why it’s been extremely difficult to get the right pain relief because there is no language for it. The nearest I can come up with is weird and wonderful similes, like bees trapped in a vent or ants crawling inside me. Working with photography has been a way of somehow getting to the core of things.”

While the long-term effects of pain can be debilitating, at the other extreme, what happens if we feel nothing at all? Would it be a blessing or a curse? CIP (congenital insensitivity to pain) was first described in the 19th century, but one of the best documented cases was Czech immigrant Edward H Gibson, a vaudeville performer known as the Human Pincushion. The Journal of Nervous and Mental Disease recorded his pain-defying stunts in 1932, where he would invite audience members on stage to skewer him with 50 to 60 pins “anywhere but the abdomen and groin”.

One of my characters, Eva, was also unable to feel pain and her symptoms were partly inspired by Jo Cameron, now in her 70s, who lives in the Highlands. Her case came to light after an operation where she needed no pain relief in recovery, even though she should have been in agony. Researchers at UCL began to investigate her rare gene mutation that means she has spent her life entirely pain-free. “I’ve never felt a thing. If something cuts or digs into me, I register the touch or the pressure, but nothing beyond that.” Often CIP sufferers die young, walking on broken limbs or placing themselves in grave danger without realising. Cameron admits she has scars everywhere and cuts her fingers regularly, not noticing until she sees the blood. “Numerous times I’ve burnt myself on the Aga and not realised until I could smell meat. I’m a vegan and you don’t get that smell much in my house,” she laughs. What is striking about Jo is how happy she appears, and maybe this isn’t just coincidence: researchers believe her genetic mutation could be linked to feeling less anxious and afraid. “When I was 71, I went zip wiring and got stuck halfway along. I knew if I dropped down, I would die instantly, but I thought if I stayed still, someone would come and fetch me. Which they did. I didn’t panic but if you never feel pain, it’s easier to think about things clearly.”

If she could, would she reverse her condition, suffer like the rest of us? Her answer is immediate. “No. I accept the way I am. I’m happy being me. When other people are in pain, I can see by their expression and the changes in them that something awful is happening. But what that awful is, I’ll never know.”

You Can’t Hurt Me by Emma Cook is published by Orion at £22. It is also available from guardianbookshop.com at £19.80, and on Kindle throughout January for 99p