Tag Archives: injury

Does a rub or a cuddle relieve pain?

I suspect most parents will have been there with a little one – a fall, a knock, a misfired football, and then the tears. In a bid to relieve the hurt, you give the sore a good rub, a strong cuddle or maybe a peck to ‘kiss it better’.

But why? Does a rub genuinely relieve pain, or is it just the only thing we can think of to show we care?

What is pain?

First, we need to understand what pain is.

Our skin and tissues underneath have different types of nerve cells coarsing through them. These help the brain sense the environment by signalling touch, temperature, pain, depending on what the fine nerve endings are set up to detect. Some nerve cells, for example, are studded with molecular receivers that grab chemicals wafting over them or change shape with varying temperature, while others fire when bent, stretched or vibrated.

When stimulated, the nerve cell pings an electrical signal down to our central nervous system, which then uses all the messages to interpret what’s going on in the environment and elicit the most appropriate action.

A gentle touch or a warm fire, will trigger our mechanoreceptors (touch) or thermoreceptors (temperature) and we may experience a nice fuzzy feeling. Pain receptors, technically known as nocireceptors, have a high threshold for stimulation. So we feel pain when certain stimuli – temperature, pressure, chemical – are intense enough to trigger the high threshold nocireceptors, which fire off signals that our brain processes as “too hot”, “too hard” or “too irritating”. This helps us take immediate action (‘move away!’) and means we generally learn what’s safe and what’s not. And while it might seem attractive to not feel pain, it causes serious problems if it isn’t there – individuals without this sense are prone to chewing chunks of their tongues off or to frequent bone breaks.

What shapes the feeling of pain?

One idea of pain relief says that stimulating the mechanoreceptors with a rub ramps up the ‘touch’ signals being sent to the central nervous system, which at least partly overrides the input from the nocireceptors. Known as the ‘Gate Control Theory‘, this shifts the balance of sensation from ‘pain’ to ‘touch’ – in a way, distracting our central nervous system with another stimulus.

There is also a special class of slow-acting touch nerve cells, triggered by gentle stroking, which seem to signal pleasurable sensations. Some studies suggest that these interact with the pain pathway to dampen painful sensations.

As well as the signals from the body, the brain coordinates input from other processing centres, which allows us to take into account past experience, from where on the body messages are being received and the context in which the stimulation is happening. Maybe that’s why a hug from a loved one can feel extra comforting.

And chemical signals in our brain shape our feelings of pain. Endorphins are chemical signals that are natural opiates so, like morphine and other opiates, can block painful sensations. They are also released in response to stress and fear, and bring the energising and euphoric feelings after exercise. Sometimes their effects are powerful enough to completely override the pain, which can be why people who have been shot sometimes only feel pain after the fearful situation has ended.

The relief of a rub

So what we actually feel is a physical and emotional experience after the brain processes the various sensory signals from the body, and takes into account past experience, environment and mood.

These may be some of the reasons why a good hug or rubbing a painful area can bring some genuine relief from hurt.