MRI study reveals Babies feel pain like adults
World-first: MRI used to study infant pain finds 18 out of 20 pain regions that activate in adult brains are also active in babies
The brains of babies ‘light up” in a very similar way to adults when exposed to the same painful stimulus, a pioneering Oxford University brain scanning study has discovered, suggesting that babies experience pain much like adults.
The study looked at ten healthy infants aged between one and six days old and ten healthy adults aged 23–36 years. Infants were recruited from the John Radcliffe Hospital in Oxford and adult volunteers were Oxford University staff or students.
During the research babies, accompanied by parents and clinical staff, were placed in an MRI scanner where they usually fell asleep. Scans were taken of the babies’ brains as they were ‘poked’ on the bottom of their feet with a special retracting rod – the sensation (“like being poked with a pencil”) was mild enough that it did not wake them up. The scans were compared with brain scans of adults exposed to the same pain stimulus.
The researchers, led by Rebeccah Slater of Oxford University’s paediatrics department, found that 18 of the 20 brain regions active in adults experiencing pain were active in babies. Scans also showed that babies’ brains had the same response to a weak poke (of force 128mN) as adults did to a stimulus four times as strong (512mN). The findings suggest that not only do babies experience pain much like adults but that they also have a much lower pain threshold.
“Up until recently people didn’t think it was possible to study pain in babies using MRI because, unlike adults, they don’t keep still in the scanner!” said Slater. “However, as babies that are less than a week old are more docile than older babies, we found that their parents were able to get them to fall asleep inside a scanner so that, for the first time, we could study pain in the infant brain using MRI.”
It is now possible to see pain ‘happening’ inside the infant brain and it looks a lot like pain in adults
“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,” added Slater. “We have to think that if we would provide pain relief for an older child undergoing a procedure then we should look at giving pain relief to an infant undergoing a similar procedure.
“Recent studies in adults have shown that it is possible to detect a neurological signature of pain using MRI. In the future we hope to develop similar systems to detect the ‘pain signature’ in babies’ brains: this could enable us to test different pain relief treatments and see what would be most effective for this vulnerable population who can’t speak for themselves.”
Goksan, S., Hartley, C., Emery, F., et al. (2015) fMRI reveals neural activity overlap between adult and infant pain. eLife doi: 10.7554/eLife.06356