British researchers have used a novel form of MRI to identify crucial developmental processes in the brain that are vulnerable to the effects of premature birth, according to a report published on Monday in the Proceedings of the National Academy of Sciences (PNAS).

The study showed that disruption of these specific processes can have an impact on cognitive function. The researchers said the new techniques developed here will enable them to explore how the disruption of key processes can also cause conditions such as autism, and will be used in future studies to test possible treatments to prevent brain damage.

Scientists from King's College London and Imperial College London used diffusion MRI - a type of imaging which looks at the natural diffusion of water - to observe the maturation of the cerebral cortex where much of the brain's computing power resides.

By analysing the diffusion of water in the cerebral cortex of 55 premature infants and 10 babies born at full term, they mapped the growing complexity and density of nerve cells across the whole of the cortex in the months before the normal time of birth.

They found that during this period maturation was most rapid in areas of the brain relating to social and emotional processing, decision making, working memory and visual-spatial processing.

These functions are often impaired after premature birth, and cortical development was reduced in preterm compared to full term infants, with the greatest effect in the most premature infants.

"We know that prematurity is extremely stressful for an infant, but by using a new technique we are able to track brain maturation in babies to pinpoint the exact processes that might be affected by premature birth." said Professor David Edwards, director of the Centre for the Developing Brain at King's College London.

"These findings highlight a key stage of brain development where the neurons branch out to create a complex, mature structure. We found that the earlier a baby is born, the less mature the cortex structure. The weeks a baby loses in the womb really matter," he added.