At the American Academy of Neurology annual meeting, researchers presented involving cognitively normal individuals that examined speech behavior in connected speech tasks to measure the trajectory of decline and how language changes due to aging.
In this exclusive video, , of the University of Miami Miller School of Medicine, describes the findings from his research.
Following is a transcript of his remarks:
My research mainly focused on examining speech behavior, specifically in this study on age-related cognitive decline across the age span. So between ages of 55 and older. We're really looking at different ways to measure how cognitive functioning degrades slightly over the age span. We're looking at different measures from picture descriptions, narrative recalls both immediate and delayed, as well as free-response tasks.
So I looked at a number of measures including lexical frequency, which are the frequency of the actual words used. So think of the difference between the words "travel" and "traverse" -- "travel" would be a lot more of a common word than "traverse." I looked at different measures including rate of speech, the number of pauses and disfluencies -- including "ums," "uhs," unfilled pauses -- and the accuracy of the content of the picture descriptions as well as the narrative recalls.
And we found some interesting results, mainly that individuals that were older tended to use a lot more adjectives and a lot more descriptive words, but without actually adding content. So they tended to just continue to describe over and over the same object or the same portion of the narrative that they're recalling, adding a bit more description than people that were a bit younger.
And our hypothesis is that this is because they were trying to just continue to add more description while thinking of the next object to describe or the next component of the story to recall. We also found that the content remains the same across the age span, which is expected. These people are not cognitively impaired, so we wouldn't expect them to be able to not recall a story that they heard or to be unable to describe a picture. Everyone basically performed the same regardless of their age.
Our main finding was that they increased their descriptiveness, they used a bit more pauses and disfluencies as they grew older. Maybe adding a little bit more time to think of the next thing to describe or to recall. But generally there was no difference in the accuracy or many of the other measures.
Overall, we were intending to look at this very subtle decline in age-related cognitive functioning, to be able to differentiate it from mild cognitive impairment or early stage Alzheimer's disease, allowing us to better target these older individuals and differentiate between normal age-related decline and pathological decline due to Alzheimer's disease, vascular dementia, frontotemporal dementia, and other types of disorders.