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The Nun Study of Aging and Alzheimer’s Disease Neurologist David Snowdon is shown here having a laugh during a card game with Sister Esther, who is 106 years old. Since 1986, Snowdon (2002, 2003) has studied 678 elderly Roman Catholic nuns, an ideal research group because their lifestyles and environment are so similar. Although the study is ongoing, several findings have already emerged (see K. P. Riley & others, 2005; Tyas & others, 2007a, 2007b).

For example, the outward signs of Alzheimer’s disease (AD) and the degree of brain damage evident at death are not perfectly correlated. Although some nuns had clear brain evidence of AD, they did not display observable cognitive and behavior declines prior to their deaths. Other nuns had only mild brain evidence of AD but showed severe cognitive and behavioral declines.

Interestingly, the sisters who displayed better language abilities when they were young women were less likely to display AD symptoms. This held true regardless of how much brain damage was evident at the time of their death (Iacono & others, 2009). As researcher Diego Iacono (2009) commented, “It’s the first time that we’re shown that a complex cognitive activity, like language ability, is connected with a neurodegenerative disease.”

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