A new study has found out why babies who are born prematurely are more likely to get autism, attention deficit disorder, and other childhood mental disorders.

Researchers at Washington University School of Medicine in St. Louis have found evidence that those who are born prematurely have weaker connections in some critical brain networks compared with babies who are born within a normal time frame, according to a WGBH report.

Cynthia Rogers, who is an assistant professor psychiatry at the university, said that the study involved comparing the brains of 58 full-term babies with 76 babies who had been born at least 10 weeks early, according to the report.

They used two different types of MRI to come to their findings, looking closely at nerve fibers responsible for sending signals between parts of the brain to determine how will it is communicating.

They found that full-term fetuses had much higher levels of connectivity in the brain compared to pre term babies, which would explain why these babies experience these problems more often than those that are brought to full term.

Scientists think that the brain circuits associated with prematurity will need to be repaired before the child is born, and that their circuits may need to be stimulated while they are in utero.

Washington University in St. Louis published a news release on the finding, which can be found here.