“Neurodevelopmental disorders” is the term used to describe impairments in growth and development of the brain. They include autism, Down syndrome, cerebral palsy, schizophrenia and traumatic brain injury.
Developmental disorders usually emerge as a child grows. They commonly affect a child's emotion, learning, self-control and memory. Catching them early is the best chance at treating them most effectively. As a result, the goal is for early diagnosis of problems and this depends on finding ways to monitor different brain regions during infancy.
And now a study reports a new approach for doing just that — measuring early brain development in a way that provides the first opportunity for predicting how a newborn's brain will develop and grow and a more accurate way of charting that brain growth.
Researchers used magnetic resonance imaging (MRI), a technology regularly used in hospitals to view internal anatomy, to map out growth in specific brain regions during the first 90 days of life. This ability to assess brain size, symmetry and growth rates may ultimately aid in detecting and treating the earliest signs of neurodevelopmental disorders.
The brain's rapid growth rates near birth suggest that inducing early labor, if not clinically warranted, may have a negative effect on the infant's neurodevelopment.
Dominic Holland, one of the study authors and a researcher in the Department of Neurosciences at UC San Diego School of Medicine, believes that having a better understanding as to how and when neurodevelopmental disorders arise so soon after birth should also make it easier to monitor treatments of newborns who appear to have problems. And being able to treat problems early, when the brain is still forming and quite plastic, could also help reduce the severity of the disorders as the child ages.
Current methods for measuring brain development in infants have relied on measuring the outside of the head on a regular basis to chart growth. Unfortunately, this approach cannot tell doctors and parents if individual brain regions are developing normally.
Using their MRI-based technique, researchers discovered that the newborn brain grows an average of 1% each day immediately following birth but slows to 0.4% per day by three months. More specifically, the cerebellum, involved in motor control, grew at the highest rate and more than doubled in volume by the end of the study, seemingly reflecting a newborn's gains in physical development.
The hippocampus, involved in memory and spatial navigation, grew at the slowest rate, suggesting these functions may be less important during the first few months of life.
Researchers also used the technique to study differences in brain development between normal and premature infants.
“We found that being born a week premature, for example, resulted in a brain four to five percent smaller than expected for a full term baby. The brains of premature babies actually grow faster than those of term-born babies, but that's because they're effectively younger — and younger means faster growth,” Holland said in a statement.
“At 90 days post-delivery, however, premature brains were still two percent smaller. The brain's rapid growth rates near birth suggest that inducing early labor, if not clinically warranted, may have a negative effect on the infant's neurodevelopment.”
The researchers hope to continue making advances in the use of MRI scans to examine the newborn brain. Future studies will investigate how the size and growth of specific brain structures are altered as a result of alcohol and drug use during pregnancy.
“Our findings give us a deeper understanding of the relationship between brain structure and function when both are developing rapidly during the most dynamic postnatal growth phase for the human brain,” Holland said.
The study is published in JAMA Neurology.