“Alzheimer’s testing” and “having fun” seem unlikely to appear in the same sentence. Enter Sea Hero Quest, a video game designed to detect early signs of memory loss.

In Sea Hero Quest, gamers are the captain of a virtual boat. They’re tasked with memorizing a map and navigating the waters with only remembered clues.

In Sea Hero Quest, gamers are the captain of a virtual boat. They’re tasked with memorizing a map, which disappears and compels them to navigate the waters with only remembered clues.

The app tracks how efficiently players reach their goals, often picking up signals of memory loss before major symptoms crop up.

Sea Hero Quest was developed in 2016 by Germany’s Deutsche Telekom in partnership with Alzheimer’s Research UK, University College London (UCL), the University of East Anglia, and game developer Glitchers; the researchers published their findings last week in the Proceedings of the National Academy of Sciences.

Sea Hero Quest isn’t just a breakthrough technology because it’s enjoyable. Its effectiveness is enough to turn a head or two; according to the developers, Sea Hero Quest gamers generate the same amount of data in two minutes of play as it would take scientists five hours to collect in a lab.

“Research shows us that the brain changes associated with diseases like Alzheimer’s begin decades before symptoms like memory loss start,” Gillian Coughlan, one of the researchers behind the game, told the University of East Anglia. “For future Alzheimer’s treatments to be effective, they must be given at the earliest stages of disease, before there’s too much damage to the brain.”

Over 4.3 million people have played Sea Hero Quest, spanning more than 117 years in game-play hours. The game is now available for VR headsets, and is an exciting look at how technology is making waves in dementia research and prevention.

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