Subtle changes in your voice could reveal your age and how well you’re aging, a study has found.
An international team of researchers analyzed the voices of nearly 3,000 adults ages 18 to 88 from five countries, including healthy people and those with Alzheimer’s disease and other forms of dementia.
Rather than looking at a single property in the participants’ voices, the team used a machine learning tool to analyze hundreds of features, including speech rate, pitch, vocabulary and emotion.
They used this to generate a ‘speech clock’ that estimated each participant’s chronological age, or their actual age in years.
The gap between this ‘speech age’ and their real age was then used to determine their biological age, or how rapidly their body was aging.
Researchers found that if someone’s ‘speech age’ was older than their chronological age they were more likely to be suffering from cognitive decline.
Dr Agustin Ibanez, senior study author and professor in Brain Health at Trinity College Dublin’s Global Brain Health Institute, said: ‘Our voice appears to contain much more information about aging than we previously recognized.
‘It captures both the passage of chronological time and signals coming from cognition, the brain, systemic biology and even our accumulated social environment.
Researchers have built a ‘speech clock’ that can predict a person’s age based on their voice, as well as signal concerns such as dementia
‘This raises the possibility that something as simple and accessible as speech clocks, maybe combined with biomarkers, could eventually complement much more expensive measures of aging.’
Overall, the researchers found that a younger voice was associated with a lower likelihood of dementia and cognitive issues.
They found that older voices tended to be slower, flatter in pitch and lacked emotional inflection, when someone changes their tone for particular words to emphasize them. Younger voices, meanwhile, were faster and did not require as many words to get a point across.
For many people, their voice develops and changes as they age.
Over time, the vocal folds, cords and complex structures that vibrate to produce a voice can lose their elasticity and become stiff, changing how the voice sounds. The lung capacity can also reduce, further changing the voice as less air can be forced out when someone speaks.
These changes do not affect everyone, but scientists say they typically begin when someone is in their 50s.
In the study, published in the journal Science Advances, researchers looked at 2,928 adults from Argentina, Chile, Mexico, Peru and Colombia.
Of the participants, 1,504 were healthy, 1,069 had Alzheimer’s and the remainder had other forms of dementia or cognitive impairment.
Overall, participants that were healthy were 61 years old on average while those who had Alzheimer’s were 71 years old on average. The majority were women. All were Spanish speakers and completed speech tests in Spanish.
The machine learning model identified six elements of speech: timing, pitch, emotion, vocabulary, correctness and how many words it took to express an idea.
People with ‘older’ speech compared to their chronological age were more likely to have poorer cognitive skills and memory than those whose chronological and biological ages matched up.
In the second part of the study, researchers compared participants’ speech age gap, the difference between their estimated speech age and chronological age, to their brain scans.
Those with larger speech age gaps had a greater likelihood of having dementia.
The team found that when the model predicted older age based on speech patterns, these individuals were more likely to have poorer memory skills, overall cognition and executive function – which measures planning, focus and multitasking – compared to people with smaller speech age gaps.
For those diagnosed with Alzheimer’s disease, larger gaps were associated with higher levels of plasma p-tau217, a blood biomarker found in the disease.
Alzheimer’s and dementia can significantly change the voice because they can leave sufferers struggling to find words, speak and suffering from swallowing problems.
The researchers revealed their ‘speech clock’ in a study, saying it could be an alternative method for calculating biological age.
They noted that while measuring biological age usually requires invasive testing such as blood samples and MRI scans, the speech clock could be implemented as a more accessible testing measure, particularly in more disadvantaged areas such as Latin America and the rural US.
They emphasized, however, that more research is needed before the test could be used on a widespread basis.
Ibanez said: ‘The broader finding is nevertheless striking in that a person’s voice may provide a remarkably compact readout of multiple dimensions of aging.
‘From chronological age to brain aging… information traditionally obtained through very different and often expensive measurements appears to converge, at least partly, in the way we speak.
‘If confirmed across populations, speech could ultimately become one of the most scalable tools for monitoring healthy and accelerated aging – potentially transforming an everyday human behavior into a window onto the biology of aging.’
