Voice disorders (cancers of the larynx, vocal fold paralysis, benign lesions on the larynx)
Obviously, vocal changes are a hallmark of these conditions, which cause things like breathiness or “roughness,” a type of vocal irregularity. Hoarseness that lasts at least 2 weeks is often one of the earliest signs of laryngeal cancer. Yet it can take months – one study found 16 weeks was the average – for patients to see a doctor after noticing the changes. Even then, laryngologists still misdiagnosed some cases of cancer when relying on vocal cues alone.
Now imagine a different scenario: The patient speaks into a smartphone app. An algorithm compares the vocal sample with the voices of laryngeal cancer patients. The app spits out the estimated odds of laryngeal cancer, helping providers decide whether to offer the patient specialist care.
Or consider spasmodic dysphonia, a neurological voice disorder that triggers spasms in the muscles of the voice box, causing a strained or breathy voice. Doctors who lack experience with vocal disorders may miss the condition. This is why diagnosis takes an average of nearly 4.5 years, according to a study in the Journal of Voice, and may include everything from allergy testing to psychiatric evaluation, says Dr. Powell. Artificial intelligence technology trained to recognize the disorder could help eliminate such unnecessary testing.
Neurological and neurodegenerative disorders (Alzheimer’s, Parkinson’s, stroke, ALS)
For Alzheimer’s and Parkinson’s, “one of the first changes that’s notable is voice,” usually appearing before a formal diagnosis, says Anais Rameau, MD, an assistant professor of laryngology at Weill Cornell Medicine, New York, and another member of the NIH project. Parkinson’s may soften the voice or make it sound monotone, while Alzheimer’s disease may change the content of speech, leading to an uptick in “umms” and a preference for pronouns over nouns.
With Parkinson’s, vocal changes can occur decades before movement is affected. If doctors could detect the disease at this stage, before tremor emerged, they might be able to flag patients for early intervention, says Max Little, PhD, project director for the Parkinson’s Voice Initiative. “That is the ‘holy grail’ for finding an eventual cure.”
Again, the smartphone shows potential. In a 2022 Australian study, an AI-powered app was able to identify people with Parkinson’s based on brief voice recordings, although the sample size was small. On a larger scale, the Parkinson’s Voice Initiative collected some 17,000 samples from people across the world. “The aim was to remotely detect those with the condition using a telephone call,” says Dr. Little. It did so with about 65% accuracy. “While this is not accurate enough for clinical use, it shows the potential of the idea,” he says.
Dr. Rudzicz worked on the team behind Winterlight, an iPad app that analyzes 550 features of speech to detect dementia and Alzheimer’s (as well as mental illness). “We deployed it in long-term care facilities,” he says, identifying patients who need further review of their mental skills. Stroke is another area of interest, because slurred speech is a highly subjective measure, says Dr. Anderson. AI technology could provide a more objective evaluation.