MRI Techniques to eExamine Age and Alzheimer-Related Changes in the Brain

David Salat

NMR Center, Massachusetts General Hospital

Theories of brain aging suggest that cortical atrophy is minimal in early adulthood, and that it is regionally selective, with earliest and most profound changes occurring in association cortex, and later and less significant changes occurring in primary sensory and motor cortex. Still, how early in the lifespan such changes begin and whether atrophy follows such a regional gradient remains unclear as prior studies have not examined age-related atrophy across the entire cortical surface. We measured the thickness of the cerebral cortex from magnetic resonance images (MRI) in 106 healthy participants ranging in age from 18 to 93. Thinning was apparent within the young participant group, suggesting that age-related cortical thinning occurs early in adulthood. Differences between younger and older adults were regionally widespread, including primary sensory and motor regions, without obvious relation to known histological or functional specificity. We conclude that cortical atrophy occurs earlier and is more widespread than previously assumed, and that current theories suggesting a progression of atrophy from association to primary sensory and motor cortex are incomplete.

The lecture will take place:

in Room 401, 44 Cummington St.
on Friday, October 25, 2002
at 11:00 am