This test can show if you're at risk of dementia

Washington D.C.: Chances are that you might end your days slipping into dementia, but now, a recent study has suggested that it's possible to detect the onset of early memory loss.

In a joint Baycrest-University of Memphis study, scientists have discovered a new potential predictor of early dementia through abnormal functionality in regions of the brain that process speech (the brainstem and auditory cortex).These brain regions are thought to be more resilient to Alzheimer's. However, this discovery demonstrates changes occur early in the brain's conversion of speech sound into understandable words.

This finding could be the first sign of decline in brain function related to communication that presents itself before individuals become aware of these problems.Their research technique of measuring electrical brain activity using an electroencephalogram (EEG) in these brain regions also predicted mild cognitive impairment (MCI), a condition that is likely to develop into Alzheimer's, with 80 per cent accuracy.

This test could be developed into a cost-effective and objective diagnostic assessment for older adults.The study looked at older adults with no known history of neurological or psychiatric illnesses with similar hearing acuity.

The brain activity within the brainstem of these older adults demonstrated abnormally large speech sound processing within seven to 10 milliseconds of the signal hitting the ear, which could be a sign of greater communication problems in the future."This opens a new door in identifying biological markers for dementia since we might consider using the brain's processing of speech sounds as a new way to detect the disease earlier," said senior author Dr. Claude Alain. "Losing the ability to communicate is devastating and this finding could lead to the development of targeted treatments or interventions to maintain this capability and slow progression of the disease."

The study involved 23 older adults between the ages of 52 and 86. Participants were separated into two groups based on their results on a dementia screening test, the Montreal Cognitive Assessment (MoCA). Researchers measured brain activity in the brainstem while participants were watching a video. They measured brain activity in the auditory cortex while participants were identifying vowel sounds.Statistical methods were used to combine both sets of brain activity to predict MCI.

"This could offer a new diagnostic assessment that tests a person's cognitive abilities, such as their ability to communicate, and objectively measure physiological changes in the brain that reflect early signs of dementia," said first author Gavin Bidelman.The study is published online in the Journal of Neuroscience.