{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T21:44:48Z","timestamp":1768599888680,"version":"3.49.0"},"reference-count":29,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T00:00:00Z","timestamp":1768521600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Brain Sciences"],"abstract":"<jats:p>Background\/Objectives: Dementia, characterised by cognitive decline, significantly impacts language abilities. While the risk of dementia increases with age, it often manifests years before clinical diagnosis. Identifying early warning signs is crucial for timely intervention. Previous research has demonstrated that changes in language, such as reduced vocabulary diversity and simpler sentence structures, may be observed in individuals with dementia. This study investigates the potential of linguistic analysis to detect early signs of cognitive decline by examining the writing of Sir Terry Pratchett, a renowned author diagnosed with Posterior Cortical Atrophy (PCA), typically a form of dementia caused by Alzheimer\u2019s disease. Methods: This study analysed 33 Discworld novels by Terry Pratchett, comparing linguistic features before and after a potential turning point identified through analysis of adjective type-token ratios (TTR). Results: A significant decrease in lexical diversity (TTR) was observed for nouns and adjectives in later works. Total wordcount increased, while lexical diversity decreased, suggesting a shift towards simpler language. This shift coincided with a decrease in adjective TTR below a defined threshold, occurring approximately ten years before Pratchett\u2019s formal diagnosis. Conclusions: These findings suggest that subtle changes in linguistic patterns, such as decreased lexical diversity, may precede clinical diagnosis of dementia by a considerable margin. This research highlights the potential of linguistic analysis as a valuable tool for early detection of cognitive decline. Further research is needed to validate these findings in larger cohorts and explore the specific linguistic markers associated with different types of dementia.<\/jats:p>","DOI":"10.3390\/brainsci16010094","type":"journal-article","created":{"date-parts":[[2026,1,16]],"date-time":"2026-01-16T09:28:12Z","timestamp":1768555692000},"page":"94","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Detecting Dementia Using Lexical Analysis: Terry Pratchett\u2019s Discworld Tells a More Personal Story"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-8499-0497","authenticated-orcid":false,"given":"Melody","family":"Pattison","sequence":"first","affiliation":[{"name":"School of English, Communication and Philosophy, Cardiff University, Cardiff CF10 3XB, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0825-1088","authenticated-orcid":false,"given":"Ahmet","family":"Begde","sequence":"additional","affiliation":[{"name":"School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK"},{"name":"Department of Psychiatry, Oxford University, Oxford OX3 7JX, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7944-2674","authenticated-orcid":false,"given":"Thomas D. W.","family":"Wilcockson","sequence":"additional","affiliation":[{"name":"School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough LE11 3TU, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,16]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"On dementia and other cognitive disorders","volume":"2","author":"Fymat","year":"2019","journal-title":"Clin. Res. Neurol."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1042\/bse0560099","article-title":"Amyloid \u03b2-peptide and Alzheimer\u2019s disease","volume":"56","author":"Allsop","year":"2014","journal-title":"Essays Biochem."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"2S","DOI":"10.1016\/S0002-9343(98)00022-9","article-title":"The initial recognition and diagnosis of dementia","volume":"104","author":"Knopman","year":"1998","journal-title":"Am. J. 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