Newborn babies can feel pain before they understand it: Study

A newborn’s brain can detect pain just days after birth, but it doesn’t yet know what that pain means.

That’s the key finding from a new University College London study that examined how pain-processing systems develop in the earliest stages of life. The research, published in the journal Pain, shows that while babies can physically sense pain shortly after birth, the emotional and cognitive systems needed to process it are still under construction.

“Pain is a complex experience with physical, emotional, and cognitive elements,” said Professor Lorenzo Fabrizi, who led the study. “In newborns, this network is still maturing, which may mean their experience of pain is vastly different from ours.”

The study used brain scans from 372 newborns — including many born prematurely — to track how three major pain-related networks form in the brain:

The sensory network, which detects pain, begins working between 34 and 36 weeks after conception.

The emotional network, which responds to the unpleasantness of pain, matures around 36 to 38 weeks.

The cognitive network, which helps interpret and understand pain, isn’t fully active until after 42 weeks.

This means even full-term babies can feel pain but don’t yet have the brain structures needed to evaluate or understand it fully. For premature babies, the gap is even wider.

The study also builds on earlier findings. In 2023, Fabrizi’s team reported that premature infants don’t become less sensitive to repeated painful procedures, suggesting they react to each one as if it’s new. The latest research could explain why — their brains haven’t developed the ability to make sense of repeated experiences.

“Our results suggest that preterm babies may be particularly vulnerable to painful medical procedures during critical stages of brain development,” said Fabrizi. “This highlights the need for pain management strategies that are tailored to a baby’s stage of neural development.”

The study was part of the Developing Human Connectome Project and was funded by the UK’s Medical Research Council. It could help shape new standards for neonatal care, especially for babies born prematurely.