Test Diagnoses Dementia While You Sleep by Estimating Your Brain Age

River D'Almeida, Ph.D
2 min readOct 3, 2020

Researchers at Harvard have discovered a novel diagnostic marker of dementia for identifying undiagnosed patients or those most at risk of developing the neurodegenerative condition.

Termed the Brain Age Index, or BAI, the diagnostic model is powered by artificial intelligence and generates a readout based on the difference between a person’s chronological age and their biological brain age. The data used by the algorithm is based on brain activity measurements taken using electroencephalogram, or EEG, while the individual is fast asleep. The higher the BAI, the faster the brain is aging, and the more likely they are to have dementia.

M. Brandon Westover, a senior author of the publication featured in JAMA Network Open said, “The model computes the difference between a person’s chronological age and how old their brain activity during sleep ‘looks,’ to provide an indication of whether a person’s brain is aging faster than is normal.”

The BAI test is a huge leap forward from current tests for estimating a person’s brain age which use expensive magnetic resonance imaging techniques that can not be feasibly taken at regular intervals to track brain activity. Moreover, the BAI can be easily measured at home using simple, cost-effective medical devices like headbands with in-built EEG electrodes.

The researchers validated their BAI platform using over 5,000 sleep tests from individuals diagnosed with dementia, those with mild cognitive impairments, undiagnosed individuals challenged with impairments and over 2,000 healthy volunteers. Clear patterns emerged wherein patients with dementia had, on average, about four years older brain ages than those without.

The researchers see BAI measurements becoming a routine part of primary care with the potential to be a powerful screening and monitoring tool for the presence of neurodegenerative illnesses.

Originally published at https://www.labroots.com on October 3, 2020.



River D'Almeida, Ph.D

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