Written language clues to cognitive changes of aging: an analysis of the letters of King James VI/I.

Reductions in language complexity normally occur in older adults because of decreased working memory and rate of language processing. Comparative measures can reveal whether linguistic change is due to normal aging or dementia. Linguistic analysis of a series of letters of King James, 1566-1625, investigate whether he exhibited a normative or atypical pattern of change. Fifty-seven letters from the years 1604 to 1624 were analyzed. Data modeling reveals a quadratic pattern of decline in written language complexity with increased diversity of vocabulary corresponding to historical reports of illness around 1618-1619. This investigation demonstrates how language analysis can provide valuable insight to normal and pathological cognitive changes of aging as well as to the understanding of historical figures.