Description: Having a higher level of education seems to delay the onset of dementia, but once cognitive decline begins, the descent is more precipitous, a new study finds. The findings confirm the so-called "cognitive reserve hypothesis," which posits that people with more education have some kind of brain "reserve" that allows them to withstand the ravages of dementia longer. Eventually, however, the disease overwhelms this reserve, and the mental decline that follows is accelerated.