Queen Elizabeth has it. So does fashion designer Victoria Beckham. And actress Kristen Stewart - poor thing, she's practically the poster girl.

Among the slew of pop culture icons said to be afflicted with so-called Resting Bitch Face (alternatively known as Bitchy Resting Face), the vast majority are women, though Kanye West is among the male examples. All of them have been mocked by internet commenters for having a certain unintentional expression when their faces are not in motion - a look best described as vaguely annoyed, maybe a little judgy, perhaps slightly bored.

Since the RBF meme took over the internet in 2013, fueled by a viral mock-PSA about "Bitchy Resting Face," legions of people have identified the dreaded phenomenon in celebrity listicles, in their own social circles, even in the mirror.

So Jason Rogers and Abbe Macbeth, behavioral researchers with international research and innovation firm Noldus Information Technology, decided to investigate: Why are some faces seen as truly expressionless, but others are inexplicably off-putting? What, exactly, makes us register a seemingly neutral expression as RBF?