London - Tiny babies are more sensitive to pain than adults, a study of infants’ brains suggests.
Until now doctors had assumed that the brains of very young babies were not developed enough to feel pain.
It means that newborns often go without painkillers, even during invasive procedures, partly over concerns about unknown effects of anaesthetics on babies.
But these Oxford University findings suggest that babies do feel pain – and have a lower pain threshold than adults.
Research showed infants’ brains react in a similar way to adults’, even to mild pain.
Dr Rebeccah Slater, of Oxford’s department of paediatrics, said: “Some people have argued that babies’ brains are not developed enough for them to really ‘feel’ pain, any reaction being just a reflex – our study provides the first really strong evidence that this is not the case.”
The study, in journal eLife, says it is possible to see pain “happening” inside the infant brain – and it looks a lot like pain in adults.
Until the 1980s it was common for babies to go through surgery with no pain relief, though they were given drugs to stop movement. A 1987 study suggested that doctors may have been wrong and anaesthetics were brought in for major operations.
But injections are still given and intravenous drips inserted without pain relief – and far more serious procedures carried out without anything to take away pain.
Even this year, NHS guidelines advise doctors to perform the procedure for tongue-tie – when the bottom of the tongue is attached to the mouth – without pain relief.
The NHS guidelines advise that, when the tongue is sliced from the mouth’s floor, “being cuddled and fed is more important than painkillers” for small babies.
Dr Slater called for a review of the way tiny babies are treated. She said: “Thousands of babies across the UK undergo painful procedures every day but there are often no local pain management guidelines to help clinicians.
“Our study suggests that not only do babies experience pain but they may be more sensitive to it than adults.”
Her team scanned brains of ten infants aged from one to six days old, and compared them those of ten adults aged 23 to 36.
MRI scans as the babies were poked mildly on the bottom of their feet with a rod found 18 of the 20 pain regions in adults’ brains also “lit up” in babies’ brains. Scans also showed babies had the same response to a weak poke as adults did to a stimulus four times the strength, suggesting infants’ thresholds for pain are lower.
Daily Mail