Ebay is analyzing your facial expressions to decide what you want for Christmas

Ebay is using "emotional recognition technology" to help shoppers decide what gifts they most want for Christmas.

The online private auction site opened a pop-up store in London on Tuesday where shoppers can enter a booth containing a screen, headphones and a camera, and browse items to find out which ones they "emotionally connect with". Sensors then analyze the person's reaction to the products they see, with the aim of providing suggestions for what people really want to give – or receive - over the Holiday season.

The technology goes further than simply recognizing the expression on someone's face, eBay claims. "Muscular micro-shifts from visitors will be captured and correlated with complex emotional and cognitive states recognized by the innovative software engine," it said in a release.

While this may sound other-worldly, the online retailer says it wants gift-buying to be emotional, rather than simply transactional. Its research shows that people become fed up with Christmas shopping after just 32 minutes.

Shoppers visiting the pop-up can browse 12 items from a variety of retailers and receive a report telling them which ones stir their feelings the most. Ebay is also donating money from some items sold on its website to a variety of charities.

This isn't the first time a business has used biometric technology, or human data such as heart rate and temperature, to inform marketing. The company behind eBay's emotional experiment, Lightwave, has previously worked with 20th Century Fox to measure viewers' physiological reactions to the 2016 movie "The Revenant" via a high-tech bracelet.

Unilever deodorant brand Degree has also used Lightwave's devices to measure fans' physical responses to a NCAA basketball championship this past March to help it understand how people move, and therefore what they need from such a product.

Clarification: This article has been updated since first published following clarification from Ebay.

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