Gaby
Many of us know the term lethologica, which refers to difficulty finding or recalling words in everyday life. This problem usually becomes more common as we age.
Struggling to find the right words can signal brain changes tied to the early (preclinical) stages of Alzheimer’s disease, often before clearer symptoms appear.
But a recent University of Toronto study found that speech rate — not word-finding problems — is the clearest indicator of brain health in older adults. The team reached that conclusion using artificial intelligence.
How the Study Was Conducted
A team asked 125 healthy adults, ages 18 to 90, to describe a scene in detail. The recordings were analyzed with AI that measured speech rate, pause length between words, and vocabulary diversity.
Volunteers also took standard tests of attention, processing speed, planning, and task execution. Age-related declines on those tests were more closely tied to everyday speech rate than to word-finding difficulties.
A crucial part of the study involved a timed task that required quick, accurate naming of specific images, as reported by Science Alert. The team found that older adults’ natural speech rate correlated with how quickly they could name the pictures.
So the researchers conclude that the main driver of cognitive and language changes with age may be a general slowdown in information processing, rather than a problem with word recall.
Why This Matters
The study opens the door for further research. It shows that to detect age-related cognitive changes early, we need to consider not just what people say but how quickly they say it.
By applying AI to speech data, the team shed new light on early dementia diagnosis. Previous work looked at subtle language changes in public figures like Ronald Reagan and Iris Murdoch that appeared years before their diagnoses. This study takes a more systematic, forward-looking approach.
Advances in speech-processing technology could enable timely, effective detection of changes such as slowed speech rate.
The scientists emphasized that changes in speech tempo are a subtle yet important marker of cognitive health. This approach could help identify people at risk before more serious dementia symptoms appear.
