The stra trut abo pai

Pain seems a fairly straightforward experience. You get hurt and, well, it hurts. But how would you describe it? By the number of broken bones or stitches? Or by the cause – the crowning baby, the paper cut, the cheating husband?

What does a seven on a pain scale of one to 10 even mean?

Pain is complicated, difficult to define and tough to explain to others.

But most of the time, the way we treat it is superficial. We avoid it at all costs or suppress it, usually with drugs.

In their new book, Ouch: Why Pain Hurts and Why It Doesn’t Have To, Margee Kerr and Linda Rodriguez McRobbie examine some fascinating facts about physical pain and how we can treat it.

Placebo has an evil twin

Most people are familiar with the placebo effect – experiencing a therapeutic benefit without actually receiving the “real” treatment.

For example, you take a sugar pill instead of paracetamol and still lose the headache.

But placebo has a lesser-known – and less celebrated – counterpart: the nocebo effect.

Just as we can generate our own pain relief, we can also generate our own pain, no cell damage required.

One of our favourite illustrations of the nocebo effect is the rubber hand illusion. This requires a willing participant and a fairly realistic prosthetic hand. With one of his or her real hands hidden from sight, the participant is told to watch the prosthetic hand in front of them.

Meanwhile, the researcher touches and prods the fake hand, while doing the same thing to the participant’s hidden real hand.

After a short time, the participant takes ownership of the fake hand, mentally replacing his or her real hand. The researcher then takes out a lighter, flicks it on and holds the flame to the fake hand – and only the fake hand.

More often than not, the participant panics because that fire hurts.

The reason participants feel pain when the fake hand is burned is because our perception of sensation is constructed both from external sensory inputs and what we expect to feel.

Our efficient sensory systems have evolved to be not only responsive but also predictive.

They essentially run an internal simulation, based on previous experience, of what’s happening in and around our bodies at all times.

In the case of the rubber hand, most of the cues of a painful episode were in place – hand, fire – so this model infers that pain is the logical outcome.

We aren’t consciously aware of this, although we become acutely aware when we get it wrong, for example, like almost falling on your face when the curb you’re stepping off turns out to be higher than expected. This processing has implications for how we experience pain: if we expect to feel it, we usually do.

That’s not to say the power of positive thinking or pretending the pain isn’t happening is enough to get us through but we may have more opportunities than we think to shape how we experience pain.

Back to the rubber hand illusion. Researchers also found that when a pain-relieving cream was applied to the “burn” on the fake hand, participants reported their pain abating. It seems

Two pints of beer are more effective than paracetamol for some kinds of pain

paracetamol, the most commonly used analgesic and fever reducer worldwide.

It’s suggested for everything from labour pains to childhood fevers to backache, migraine and broken bones. The snag is, it only works some of the time and only for some types of pain.

For example, recent studies have found paracetamol only offered a very small improvement in pain ratings and mobility of people suffering from hip or knee osteoarthritis.

There was a small benefit to people suffering tension headaches but it worked no better than placebo for people with lower back pain.

In fact, even more recent evidence suggests drinking two pints of beer is more effective than taking paracetamol in relieving certain kinds of pain.

That doesn’t mean we should all crack open a bottle the next time we have backache but what it does mean is we should be a bit more sceptical about the broad claims of over-the-counter