In the study, published in the July 13 issue of Neurology, researchers looked at Alzheimer's patients with similar levels of brain cell loss due to the disease.
Head size is one way to measure brain growth and brain reserve, says study researcher Robert Perneczky, MD, of the Technical University of Munich in Germany. While brain growth is determined, in part, by genetics, size also is influenced by nutrition, infections and inflammations of the central nervous system, and brain injuries.
"These results add weight to the theory of brain reserve, or the individual capacity to withstand changes in the brain," Perneczky says in a news release. "Our findings also underline the importance of optimal brain development early in life since the brain reaches 93% of its final size at age six."
Therefore, he says, "improving prenatal and early life conditions could significantly increase brain reserve, which could have an impact on the risk of developing Alzheimer's disease or the severity of symptoms of the disease."
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