The Brain's Midlife Crisis

Myelin is a fatty sheath that covers certain nerve cells and acts rather like insulation around electrical wiring. As the brain continues to develop in adulthood and as myelin is produced in greater and greater quantities, cholesterol levels in the brain grow and eventually promote the production of a toxic protein that attacks the brain. The protein attacks myelin, disrupts message transfer through the axons and eventually leads to the development of plaques and tangles in the brain.

MRI scans also point to the fact that the later developing neural networks are the first to be affected as myelin begins to break down. This breakdown tends to begin in middle age, but it is a slow degenerative process, not revealed until the later years (60+). Lifestyle changes in middle age could therefore help to maintain myelin and may help protect against Alzheimer's.

Researchers at the UCLA school of medicine have suggested a number of preventive therapies worth investigating. These include cholesterol and iron-lowering medications, anti-inflammatory medications, diet and exercise programs and possibly hormone replacement therapy designed to prevent menopause rather than simply ease the symptoms. In addition, education or other activities designed to keep the mind active may stimulate the production of myelin. Finally, there may be ways to address genetic and environmental factors that accelerate the degeneration process.