If only companies could read shoppers’ minds, they’d know exactly what to provide and when to provide it. Alas, because no such telepathic technology exists (yet), Expedia is taking another tack, tracking facial movements to gain insight into customers’ emotions while they’re booking travel online.

Researchers in Expedia’s “usability” lab in London have been hooking subjects up to sensors that record tiny muscle movements in their faces while they’re booking travel, a procedure that Bloomberg’s Jeremy Kahn experienced first-hand.

“The lab allows us to see how people emotionally engage with the site,” said Gary Morrison, Expedia’s senior vice president of retail and brand.

Even if subjects aren’t aware they’re even having any feelings during the process, the electrodes can detect emotional responses, and eye tracking technology lets researchers see what subjects are looking at while they’re having those emotions. Researchers also might ask subjects what’s motivating their emotions.

This process is designed to help Expedia come up with new ways to reduce the stress and frustration many feel when booking travel or hotels online. The company’s UK division conducted a survey that found more than 75% of respondents considered buying a vacation online to be just as stressful as a bad day at the office, being stuck in traffic, or fighting with a loved one.

So what gave consumers the warm fuzzes? Participants responded most positively to photos of hotel rooms depicting attractive sights outside the room’s windows, instead of those that focused on the bed. Such an insight might help a hotel operator change the photos they use to list rooms and thus, get a boost in their Expedia bookings.

Want more consumer news? Visit our parent organization, Consumer Reports, for the latest on scams, recalls, and other consumer issues.