The gold/blue dress was, of course, one of the great modern viral news stories. It was simple, genuinely bizarre and everyone had an opinion on it. It also ignited furious Twitter debates and provoked a whole lot of head-scratching by scientists and other experts.
Now strap yourselves in because we’ve just found another illusion that is yet again tearing the internet apart at the seams.
A short audio clip of a computer-generated voice, which first appeared on Reddit, can be heard saying a name – but people can’t agree on whether that name is “Yanny or Laurel.”
Have a listen for yourself…
For what it’s worth, I hear “Yanny.”
But Twitter is not having it and people are now bitterly divided.
The Big Sick star Kumail Nanjiani said: “I heard Yanny all day and now I’m hearing Laurel on the same device and I can’t hear Yanny anymore. I guess I’ll just go fuck myself.”
But model Chrissie Teigen wrote: “It’s so clearly laurel. I can’t even figure out how one would hear yanny.”
And of course plenty of other people were just taking the piss out of the whole thing.
Read more: This optical illusion is absolutely amazing
So what’s the answer?
According to Lars Riecke, an assistant professor of audition and cognitive neuroscience at Maastricht University who spoke to The Verge, it comes down to frequency.
“The acoustic information that makes us hear Yanny is at a higher frequency than the acoustic information that makes us hear Laurel,” he said. “If you remove all the low frequencies, you hear Yanny. If you remove the high frequencies, you hear Laurel.”
Riecke adds that variations in the audio system playing the sound, the mechanics of your ears and what you’re expecting to hear could also play a part.
In fact, one Twitter user posted a clip showing how an adjustment of the bass can change what you hear. Pretty cool.