A novel model of human brain aging developed by a University of California-Los Angeles neuroscientist identifies midlife breakdown of myelin, a fatty insulation coating the brain's internal wiring, as a possible cause of Alzheimer's disease later in life, the university announced Monday.

Detailed in the January edition of the peer-reviewed journal Neurobiology of Aging, the model presents opportunities to explore how lifestyle changes, hormone replacement therapy, higher education or treatment with common medications in middle age might help brains remain healthy longer.

"This model embraces the human brain as a high-speed Internet rather than a computer. The quality of the Internet's connections is the key to its speed, fidelity and overall capability," said Dr. George Bartzokis, the author and visiting professor of neurology at UCLA's David Geffen School of Medicine.

"Close analysis of brain tissue and MRIs clearly shows that the brain's wiring develops until middle age and then begins to decline."