New Delhi: The way a person speaks — from tone and fluency to emotional colouring and vocal effort — may offer early clues to depression, according to research underway at the All India Institute of Medical Sciences (AIIMS) Delhi.
According to researchers, speech analysis could become an objective assistive tool to flag depressive symptoms early, especially in community settings with limited access to mental health care.
At an advanced Speech Health Lab set up at AIIMS Delhi with CSR support, researchers analysed speech samples from 423 participants with complete clinical and demographic records. The mean participant age was about 24 years, with most between 18 and 25.
Nearly two-thirds were under 23 and about 75% under 25, showing stronger engagement among younger users with low-barrier, speech-based mental health platforms. While ages ranged from adolescence to older adulthood, participation declined steadily after the mid-30s.
Standard psychiatric screening showed that around 32% had clinically meaningful depressive symptoms. When matched with automated speech analysis, prediction accuracy ranged between 60% and 75%, rising to nearly 78% when longer samples were assessed.
The lab studies linguistic features such as fluency and articulation, along with paralinguistic markers, including tone, pitch, emotional resonance and vocal energy.
Researchers found depression often alters speech—reducing fluency, flattening prosody and lowe-ring vocal effort —and stress that these models are intended to support early screening and referral, not replace clinical diagnosis. .
“Analysis of speech offers a promising way to objectively identify signs of depression, as the cognitive and behavioural changes linked to the condition influence both the production and quality of speech. Patients with depression often show reduced fluency, diminished prosody or monotonous speech,” said Dr Nand Kumar, professor, department of psychiatry, AIIMS Delhi.
Amid rising concern over depression, which affects over 264 million people globally, India’s National Mental Health Survey 2015 found one in 20 experience depressive disorders, with suicide a major risk.
Early detection is critical: a study by the National Institute of Mental Health and Neurosciences of 8,542 college students across 15 cities found one-third had moderate to severe symptoms, and nearly one in five reported suicidal thoughts.
