Impaired functional connectivity in preterm brains

In their research "Impact of preterm birth on structural and functional connectivity in neonates" presented at the Society for Neuroscience (SFN) conference in Chicago, Oct 19, 2015, Cynthia Rogers and her colleagues at Washington University Neonatal Development Research Lab, Washington University School of Medicine in St. Louis have found that key brain networks involved in attention, communication and emotion were weaker in premature infants, suggesting an explanation for why children born prematurely may have an increased risk of psychiatric disorders.

They used functional magnetic resonance imaging and diffusion tensor brain imaging to compare 58 babies born at full term with 76 infants born at least 10 weeks early. Each full-term baby was scanned on his or her second or third day of life. Each premature baby, meanwhile, received a brain scan within a few days of his or her due date. The study found significant differences in the white matter tracts and abnormalities in brain circuits in the infants born early, compared with those of infants born at full term. 

The researchers also found differences in the preterm babies resting-state brain networks, particularly in a pair of networks previously implicated in learning and developmental problems. Among these resting-state networks is the default mode network, which tends to be most active when people are least active. The greatest differences between full-term and preterm babies were seen in this network and in the frontoparietal network. Both encompass brain circuits associated with emotion and previously have been linked to ADHD and autism spectrum disorders. ICNApedia had earlier reported on an UCLA study which reported that brain areas linked to social behaviors are both underdeveloped and insufficiently networked in youths with high functioning autism spectrum disorder (ASD). The UCLA study found increased local functional connectivity (FC) in the anterior module of the default mode network (DMN) accompanied by decreased CBF in the same area. In the United States one of every 9 nfants is born prematurely and, thus, with increased risk of cognitive difficulties, problems with motor skills, and attention deficit-hyperactivity disorder (ADHD), autism spectrum disorders and anxiety.

According to the Cynthia and her team at Washington University School of Medicine these brain circuit abnormalities are likely to contribute to problems as the children get older. They are continuing to follow the babies, having completed follow-up evaluations when the children reached age 2, and again on some at age 5. The researchers plan another series of brain scans in a few years as the original study participants reach the ages of 9 or 10. The findings of these study are very encouraging and suggest a role for early intervention in influencing the long term outcome following preterm birth. {audio}101489.mp3{/audio}

Cover image: A comparison of brain scans from babies born at full term and at least 10 weeks prematurely shows differences in the activity of brain networks. The red and yellow areas represent coordinated activity. In preemies, the red areas are smaller due to less coordinated activity between these regions. (Credit: Washington University School of Medicine)