A recent study of long term data collected on over 600 nuns from Minnesota has shown that those with the greatest language skills were better off at thwarting Alzheimers disease and dementia later in life.
 
Despite still having developed brain lesions such as plaques and tangled neurological-tissue fibers that are indicative of dementia and Alzheimer’s disease, those nuns with the greater language skills still retained their cognitive abilities.

The correlation was striking: the young women who had more sophisticated language skills - defined as the density of ideas per every 10 written words - were far less likely to suffer from Alzheimer’s or dementia five, six or seven decades later.
Iacono effectively picked up where Snowdon left off. Iacono and his colleagues discovered that not only did nuns who avoided dementia later in life have 20% higher linguistic scores as young women, compared with peers who developed symptoms of cognitive decline, but that the relationship held up even in nuns whose brains showed all the physical signs of Alzheimer’s. “There is a special group of people who have comparable amount of plaques and tangles - the typical marks of the disease - without the cognitive impairment,” says Iacono. “[It appears that] people with higher linguistic scores were protected even in the face of higher pathology.”