Virtual Reality Test detects Alzheimer’s disease decades before it starts

The results also hint at a possible new target – grid-cell and EC region function – for AD therapy. As we move around, the grid activates like an internal Global Positioning System, tracking our movements and creating mental maps that allow us to navigate without visual cues. “If you close your eyes and walk ten feet forward and turn right and walk three feet forward, the grid cells are believed to [track your position]”, says neuroscientist Joshua Jacobs at Columbia University.

The at-risk group showed a different brain signal many decades before the onset of the disease, and they navigated differently in a virtual environment (…) Our results could provide a new basic framework for preclinical research on Alzheimer’s disease and may provide a neurocognitive explanation of spatial disorientation in Alzheimer’s disease. In 2005, the EC region was discovered to contain cells known as “grid cells”, a type of neuron (found in many species, including humans) responsible for maintaining spatial orientation and self-positioning.

The researchers recruited two groups of young adults without symptoms of Alzheimer’s. One in 6 people carry this APOE4 variant, which comes with a threefold greater risk of developing Alzheimer’s than non-carriers. The tasks were meant to test the participant’s spatial acuity. The space had blue sky, a few mountains in the distance, and a grass floor that was littered with everyday objects like basketballs and eggplants.

Using an advanced form of MRI to monitor the participants’ brain, researchers were most interested in the entorhinal cortex, where “grid cells” are located. Strangely, though, both groups performed equally well with the virtual arena tasks, although the way the groups navigated the space was different.

“Our studies may contribute to a better understanding of early changes of Alzheimer’s dementia”, said Axmacher. As pointed out by the paper, the grid cells are the first brain structures to be affected by Alzheimer. “This suggests that you can either use the grid cell system or you can use the hippocampus”, he says.

Virtual reality (VR) is being used for all sorts of medical breakthroughs recently. Yet, the second group used the entire area.

The researchers said it’s too soon to know whether the brain differences are a harbinger of Alzheimer’s. But it also offers a potential new avenue of study.

The Alzheimer’s Association has more on the causes of Alzheimer’s. By studying its effects, the scientists hoped they could find clues to unlock early on detection.