Tracking discourse complexity preceding Alzheimer's disease diagnosis: a case study comparing the press conferences of Presidents Ronald Reagan and George Herbert Walker Bush.
Level 4 - case-series / case-control
Level 4 comparative case study / historical case-control.
PubMed 25633673 · doi:10.3233/JAD-142763
What was done
Transcripts of non-scripted news conferences from President Ronald Reagan (diagnosed with Alzheimer's disease in 1994) and President George H.W. Bush (no known Alzheimer's diagnosis) were analyzed. Key lexical features previously linked to cognitive decline—including unique word counts, conversational fillers, and non-specific nouns—were extracted and evaluated over time using regression analyses.
What was found
President Reagan showed a statistically significant reduction in the number of unique words over time, alongside a statistically significant increase in conversational fillers and non-specific nouns. President Bush exhibited no significant trends in these features. The abstract does not report specific numerical values, effect sizes, or p-values.
Why it matters
This study provides proof-of-concept that automated longitudinal tracking of lexical features in spontaneous discourse can identify language changes preceding a clinical Alzheimer's diagnosis.
Limits
The sample is limited to two individuals (n = 2), precluding generalizability. The abstract does not report the total number of press conferences analyzed, the exact time spans, or numerical statistical outputs. Factors such as normal aging, stress, and political context were not controlled.
Cited by
- supports Linguistic and speech cues of neurodegenerative conditions like Alzheimer's disease can be detected up to 10 years before typical clinical symptoms appear.