Premature Babies May Have A Higher Risk Of Developing Autism

The connections formed in the brains of premature babies may put them at a higher risk of autism, suggests a new study. A lot of important brain development happens during the first 40 weeks of gestation and whether this happens inside or outside of the womb seems to affect brain development.

The results indicate that the earlier the birth, the more differences there are in the wiring of the brain. As a result, premature babies are more at risk of neurodevelopmental problems, including autism and attention deficit disorders (ADD).

The study, published in the Proceedings of the National Academy of Sciences (PNAS), compared the MRI brain scans of 66 infants on average 42 weeks after their mothers' last period before becoming pregnant. Of these babies, 19 were born 'in-term,' which is within an average of 40 weeks after gestation—the standard time for a pregnancy. Forty seven babies were born premature, prior to 33 weeks.

Between 37 and 42 weeks, the thalamus and cortex regions of the brain rapidly develop connections. Most of these connections form while the baby is still inside the womb, so scientists are interested in how these connections change when a premature baby develops them outside of the womb in a neonatal unit.

Babies that were born in-term were found to have mature brain connections, similar to those of adults. However, the premature babies didn't have as many links between their thalamus and cortex, which are regions associated with higher cognitive functions. This deficit is speculated to be associated with a higher number of difficulties later in life.

Interestingly, it was also noted that the premature babies had more wiring between their thalamus and primary sensory cortex. This region is associated with processing signals from the face, lips, jaw, tongue and throat. It is speculated that these connections are strengthened by a premature infant's early exposure to breastfeeding, bottle feeding and dummies.

Areas that had a similar number of connections in premature and in-term babies were regions of the thalamus involved in vision, hearing and sensorimotor activity, which is the process of receiving sensory information from the environment and producing a motor, or movement, response. 

Using this research, scientists hope to pinpoint which styles of care and medication are the most effective for premature babies.

“The ability of modern science to image the connections in the brain would have been inconceivable just a few years ago, but we are now able to observe brain development in babies as they grow,” Dr. David Edwards, senior author and a professor at King's College London, stated in a press release. “This is likely to produce remarkable benefits for medicine.”

The research doesn't just end a few weeks after a baby is born. Dr. Hilary Toulmin, first author from King's College London, said: "The next stage of our work will be to understand how these findings relate to the learning, concentration and social difficulties which many of these children experience as they grow older."