According to a new study at the Washington University School of Medicine in St. Louis, the cause for learning and attention difficulties are linked to brain tumor disorder at the time of birth which is more complex that ever thought, reports Medical Xpress.
Neurofibromatosis 1 - NH1 is a known disorder commonly found among the inherited pediatric brain tumor conditions. Most common problems among the children born with NH1 are learning and attention difficulties. "While one of our top priorities is halting tumor growth, it's also important to ensure that these children don't have the added challenges of living with learning and behavioral problems," said senior author David H. Gutmann, MD, PhD, the Donald O. Schnuck Family Professor of Neurology, according to Medical Xpress. "Our results suggest that learning problems in these patients can be caused by more than one factor. Successful treatment depends on identifying the biological reasons underlying the problems seen in individual patients with NF1."
Previous studies showed memory and attention difficulties arose in some NF1 mice models due to increased RAS activity due to improper NF1 gene function. Changes in the NF1 gene can disturb the normal functioning of the important gene called RAS. Gutmann and collaborator David F. Wozniak, PhD, research professor in psychiatry, showed in their early studies that changes in the NF1 gene lowers the levels of dopamine which is essential in attention, according to Medical Xpress.
In the latest study Kelly Diggs-Andrews, PhD, agrees with these previous findings. She found in NF1 mice that dopamine nerve cells are shorter and not reaching the hippocampus, an area of brain responsible for learning.
Researchers gave NF1 mice L-DOPA, which increases dopamine levels and found that it restored their nerve cell branches to reach out to hippocampus and also cured the memory and learning difficulties in mice.
"These results and the earlier findings suggest that there are a variety of ways that NF1 may cause cognitive dysfunction in people," Gutmann said. "Some may have problems caused only by increased RAS function, others may be having problems attributable to reduced dopamine, and a third group may be having difficulties caused by both RAS and dopamine abnormalities."
This study is published in an online journal Annals of Neurology.
