It is well established that babies born prematurely are at greater risk for developmental disabilities. Now, new research suggests this may be because preterm birth weakens brain connections associated with attention, communication and emotion.
Dr. Cynthia Rogers, assistant professor of child psychology at the Washington University School of Medicine, and colleagues will present their findings at Neuroscience 2015 - the Society of Neuroscience's annual meeting held in Chicago, IL.
According to the Centers for Disease Control and Prevention (CDC), preterm birth - defined as the birth of an infant before 37 weeks of pregnancy - affected 1 in every 9 children born in the US in 2012.
Preterm birth is a primary cause of neurological disabilities among children in the US, with babies born prematurely at greater risk for cognitive impairment, autism and attention-deficit hyperactivity disorder (ADHD), as well as psychiatric problems such as anxiety.
For their study, Dr. Rogers and colleagues set out to gain a better understanding of how preterm birth impacts the brain, with the aim of shedding light on how preterm birth leads to neurological and psychiatric problems among children.
Brain scans of preterm, full-term infants compared
The team used functional magnetic resonance imaging (fMRI) and diffusion tensor imaging to scan the brains of 76 infants born a minimum of 10 weeks early, alongside the brains of 58 babies born full term.
- In 2012, around 450,000 infants in the US were born prematurely
- Hearing loss, breathing difficulties and vision problems are some of the other conditions preterm babies may face
- Preterm-related causes of death accounted for 35% of all infant deaths in the US in 2010.
The brain scans of preterm infants were conducted within a few days of their due date, while the scans of full-term infants took place 2-3 days after birth.
Compared with full-term infants, the researchers found that the brain networks related to communication, attention and the processing of emotions were weaker among babies born prematurely.
Specifically, the team identified abnormalities in the white matter tracts of preterm infants, which consist of axons that link brain regions in order to form networks.
In addition, the researchers identified differences in the resting-state brain networks of preterm infants that have previously been linked to learning and developmental disorders.
In particular, there were significant differences between the default mode and frontoparietal networks of preterm infants, compared with full-term infants. Both networks are related to emotion and have been associated with ADHD and autism.
Based on these findings, Dr. Rogers and colleagues hypothesize that the differences identified in the brain networks of preterm infants are likely contributors to the neurological and developmental problems they often experience in later life.
Early interventions may improve outcomes for preterm babies
With the aim of confirming their theory, the team has already completed follow-up assessments on the children at the ages of 2 and 5 years. They also plan to carry out further brain scans when the children reach 9-10 years of age.
"We're analyzing the data we've already gathered, but we want to bring the children back when they are 9 or 10 and continue to follow their development," says Dr. Rogers. "We want to look at the evolution of brain development in full-term versus preterm babies, and we want to know how that may affect who is impaired and who is not."
Ultimately, the team hopes that because the brain is very "plastic" early in life, early intervention strategies may help reduce the risk of later-life neurological and psychological problems among preterm infants. Dr. Rogers adds:
"We usually can't begin interventions until after symptoms develop, but what we're trying to do is develop objective measures of brain development in preemies that can indicate whether a child is likely to have later problems so that we can then intervene with extra support and therapy early on to try to improve outcomes."
Earlier this year, Medical News Today reported on another study aiming to shed light on why preterm babies are at greater risk for developmental delay. Conducted by researchers from King's College London in the UK, the study found preterm infants have reduced connectivity in areas of the cortex related to cognitive functioning.