Children as young as five use the same brain areas for reading as adults do, according to George Washington University researchers. Their findings contribute to the understanding of cognitive skills development and learning disabilities, and may also be helpful in the management of young patients with brain damage.
Investigators assessed 16 normal children, aged five to seven, who underwent functional MRI and neurologic examination. They found that the neural networks used in reading are well developed and specifically located by the age of seven, and they are the same as in adults. Results were published in the Jan. 14 issue of Neurology.
"FMRI can be used as a tool to identify networks involved in cognitive functions in children as young as five, and in a reliable fashion," said lead author Dr. William Davis Gaillard, an associate professor of pediatrics and neurology at GWU's Children's National Medical Center. "The technique can also be used to try to understand how disease states affect the organization of such brain networks."
Although the study does not say much about reading skills per se, it does suggest that as soon as a child learns to read, a relatively "mature" pattern of brain activation is seen. The study may also help researchers confirm theories about the existence of even more and varied networks at younger ages. More work in this area is needed, however, Gaillard said.
"We are not capturing the very early reading process -- the first words -- and we do not have a large population with varied reading abilities, so it is possible that there are other variant networks, perhaps less mature, that we are not picking up," he said.
The study may also have implications for the management of young children with brain tumors or injuries, and it might prove helpful in assessing and documenting response to therapeutic intervention. FMRI may help identify and spare language areas in children who undergo brain surgery. It could also assist in designing learning strategies for children who have suffered brain injury to the left hemisphere but use "residual" networks on the right side of the brain, Gaillard said.
"Functional MRI may have importance for predicting clinical outcome after ablative neurosurgical procedures, and in terms of understanding and predicting the degree of language acquisition that may occur in children who have other pathology associated with language," said Dr. Bart P. Keogh, a radiology resident at the University of Washington in Seattle.
Specialists have traditionally avoided brain MRI examinations in children younger than 10. This study, however, shows that fMRI can be used as a tool to reliably identify networks involved in cognitive functions in very young children, said Dr. Dean K. Shibata, an assistant professor of radiology at the University of Washington.
"Most people have avoided children younger than nine or 10, sometimes because it's more difficult to get them to cooperate. This study brings some encouragement that other researchers should try to look at children in this age range," he said.
According to Shibata, future trials should focus not only on learning disabilities in children, but also on whether it is possible to help these children acquire basic cognitive skills at a younger age.
For more information from the Diagnostic Imaging archives:
Researchers map music hot spots in the brain http://www.dimag.com/db_area/onlinenews/2003/2003011501.shtml Aggressive adolescents show changes on fMRI http://www.dimag.com/db_area/onlinenews/2002/2002121301.shtml
