It's possible, he said, that diabetes affects the way that vessels bring blood to the brain.
The good news is that it appears these effects fade once type 2 diabetes disappears, he said, suggesting how important it is to help obese kids lose weight.
But trouble looms for those who remain overweight. "As the rate of obesity continues to raise in children, this will be first generation who are likely to have a much diminished lifestyle and diminished quality of life because of these issues that are ultimately fixable," he said.
Roger A. Dixon, a professor of psychology who studies diabetes at the University of Alberta in Canada, stressed that the findings are preliminary.
But he added that "it's also a very promising direction of research" that can help researchers understand if there's a connection between the effects of diabetes on the brains of older adults and the effects on children and younger adults.
The study appears online in the journal Diabetologia.
Learn about recipes for kids with diabetes from kidshealth.org.
SOURCES: Antonio Convit, M.D., professor, psychiatry, New York University Langone Medical Center and Nathan S. Kline Institute for Psychiatric Research; Roger A. Dixon, Ph.D., Canada Research Chair, cognition and aging, and professor, psychology, University of Alberta, Canada. July 30, 2010, Diabetologia
All rights reserved