White matter is the tissue in the brain that contains axon fibers,
which connect neurons in one brain region to neurons in another region.
White matter is critical for normal brain function, and little is
known about how white matter develops in humans or how it is related to
growth of cognitive skills in early childhood, including language
A new study led by UNC School of Medicine researchers concluded that
patterns of white matter microstructure present at birth and that
develop after birth predict the cognitive function of children at ages one
‘Understanding the cognitive function of children by studying the pattern of white matter could help identify cognitive problems and psychiatric disorders very early and develop appropriate interventions.’
"To our knowledge, this study is the first to measure and describe
the development of white matter microstructure in children and its
relationship to cognitive development from the time they are born until
the age of two years," said John H. Gilmore, senior author of the
study and director of the Early Brain Development Program in the UNC
Department of Psychiatry.
The study was published online on in the Proceedings of the National Academy of Sciences
In the study, a total of 685 children received diffusion
tensor imaging (DTI) scans of their brains. DTI is a magnetic resonance
imaging (MRI) technique that provides a description of the diffusion of
water through tissue, and can be used to identify white matter tracts in
the brain and describe the organization and maturation of the tracts.
The study authors used these brain scans to investigate the
microstructure of 12 white matter fiber tracts important for cognitive
function, their relationship to developing cognitive function and their
heritability. They found all 12 of the fiber tracts in the newborns were
highly related to each other.
By age one, these fiber tracts had begun to
differentiate themselves from each other, and by age 2 this
differentiation was further advanced. The most interesting finding from
the study was that the common relationship between white matter tracts
at birth predicted overall cognitive development at age one and language
development at age two, indicating that it may be possible to use brain
imaging at birth to better understand how a child's cognitive
development will proceed in the first years after birth.
Because the sample included 429 twins, the study authors were also
able to calculate that this predictive trait was moderately heritable,
suggesting that genetics may be a factor in its development.
"There is rapid growth of brain structure, cognition and behavior in
early childhood, and we are just starting to understand how they are
related," Gilmore said "With a better understanding of these
relationships, we ultimately hope to be able to identify children at
risk for cognitive problems or psychiatric disorders very early and come
up with interventions that can help the brain develop in a way to
improve function and reduce risk."
In addition to Gilmore, authors of the study are Seung Jae Lee,
Rachel J. Steiner, Yang Yu, Sarah J. Short, Michael C. Neale, Martin
Styner, and Hongtu Zhu. All are at UNC except for Neale, who is in the
Virginia Institute of Psychiatric and Behavioral Genetics at Virginia