How virtual reality can help diagnose early Alzheimer’s disease
An exciting new study from the University of Cambridge is demonstrating how a novel virtual reality navigation test can better predict which patients are in the early stages of Alzheimer's disease compared to other currently used "gold standard" cognitive tests.
For some time researchers have known that one of the earliest parts of the brain to suffer from neurodegeneration related to Alzheimer's disease is the entorhinal cortex, a region of the brain particularly involved in matters of spatial navigation. Mild cognitive impairment (MCI) is also often one of the earliest signs of Alzheimer's disease. However, MCI does not always lead to Alzheimer's as it can just be a simple byproduct of aging, treated effectively with straightforward physical exercise.
The idea behind the development of this new VR-based diagnostic tool is that a navigation test could help distinguish which patients with MCI are more likely to progress into full-blown Alzheimer's disease.
"The brain cells underpinning navigation are similar in rodents and humans, so testing navigation may allow us to overcome this roadblock in Alzheimer's drug trials and help translate basic science discoveries into clinical use," says Dennis Chan from the University of Cambridge. "We've wanted to do this for years, but it's only now that VR technology has evolved to the point that we can readily undertake this research in patients."
The researchers developed a VR navigation task expressly designed to test whether a person's entorhinal cortex was impaired. To establish whether the test could differentiate levels of Alzheimer's risk from a single cohort of MCI patients, the researchers examined 45 subjects with MCI. Samples of cerebrospinal fluid were taken from all the MCI subjects to test for Alzheimer's-related biomarkers, with 12 testing positive to these biomarkers.
After undergoing the VR navigation test the researchers discovered that all the MCI subjects with Alzheimer's biomarkers performed worse on the task than those MCI subjects with no early Alzheimer's signs. The VR test was also found to better identify those high-risk Alzheimer's patients than any other cognitive test currently used in clinical or research practice.
As well as potentially offering clinicians a simple early detection tool to catch patients with Alzheimer's, the researchers say the test could be incredibly helpful in future Alzheimer's drug trials. The VR test could be used as a metric for monitoring the progression of the disease and potential cognitive improvements in subjects trialing potential drugs.
One of the next steps for the researchers is to streamline this discovery into a useful app that could incorporate this particular test into a suite of other easily accessible measurements to detect the onset of Alzheimer's and monitor its progression.
"We live in a world where mobile devices are almost ubiquitous, and so app-based approaches have the potential to diagnose Alzheimer's disease at minimal extra cost and at a scale way beyond that of brain scanning and other current diagnostic approaches," adds Chen.
The new study was published in the journal Brain.
Source: University of Cambridge