Canadian Study Links Speech Patterns to Cognitive Decline

Natural speech patterns may serve as indicators of cognitive decline, including early signs of dementia, according to a study conducted by a research team from Baycrest Hospital, the University of Toronto, and York University. The findings, published on October 18, 2023, reveal that aging adults exhibiting long pauses, excessive filler words, and difficulty articulating thoughts may be showing signs of deteriorating brain health.

The research, led by Jed Meltzer, senior author and a clinician at Baycrest, stemmed from a fascination with how changes in speech could signal cognitive health issues. Meltzer explained in an interview with CTV News that the study utilized two cognitive assessment experiments conducted in 2019 and 2023, involving 67 healthy adults aged 65 to 75 in the first study and 174 healthy participants aged 18 to 90 in the second.

In both assessments, participants underwent standard tests measuring mental ability alongside tasks that required them to describe complex images. Meltzer noted that these tasks included colour-word interference tests designed to evaluate executive function. The team analyzed speech samples using an advanced computer algorithm developed by Winterlight Labs, a Toronto-based technology company. This algorithm can quickly detect signs of cognitive impairment by evaluating aspects such as sentence complexity and the frequency of repeated or rare words.

The results revealed that participants faced the most challenges with timing-related aspects of speech. The frequent use of filler words like “um” and “ah” and prolonged pauses were highlighted as indicative of cognitive decline. Meltzer remarked, “Talking slower is related to thinking slower,” suggesting that these speech changes may signal a deterioration in cognitive function.

While the use of filler words is not inherently indicative of cognitive delay, Meltzer cautioned that an increase over time could be a cause for concern. “If you do it more than you did five years ago, maybe you want to take a look at your cardiovascular health,” he stated.

Although Meltzer emphasized that their research does not provide a definitive diagnosis for cognitive decline, it can serve as an early detection tool. He explained that repeated assessments over time can reveal significant changes in cognitive health: “If you test someone once, they may have dementia, or they may not … but you can’t definitively diagnose someone from one examination. However, comparing tests conducted a year apart can show whether someone is undergoing serious decline.”

The research team at Baycrest harbors hopes that their findings could contribute to evaluating the effectiveness of dementia treatments and drugs. Meltzer also identified modifiable risk factors that may help delay cognitive disorders, such as enhancing social interactions and increasing physical activity. He stated, “The single best thing you can do is go on a walk with your friend.”

Other protective factors that may help prevent cognitive decline include bilingualism and higher levels of education, which, while not stopping brain damage, can increase resilience against cognitive challenges. Conversely, factors such as old age and genetics are beyond control and remain significant risk factors for a range of cognitive disorders.

This study underscores the potential for speech analysis to play a crucial role in monitoring cognitive health, offering a promising avenue for early detection and intervention in aging populations.