We’ve got a little experiment for you. First, turn off your speakers. Now, look at this totally silent gif of a bouncing pylon:
Chances are it felt like you heard a deep thudding sound. Weird, right?
The gif, created by 3D artist and animator Chris Ollis, was shared on Twitter by scientist Lisa DeBruine at the weekend. She asked her followers: “Does anyone in visual perception know why you can hear this gif?” It’s now gone massively viral after being shared and liked more than 40,000 times.
In a Twitter poll, 70% of people agreed that they could hear a thudding sound.
What do you experience when you watch this gif?— Lisa DeBruine 🏳️🌈 (@lisadebruine) December 3, 2017
And the fascinating gif has now sparked a flurry of scientific speculation about what causes the strange phenomenon.
DeBruine said: “My favourite explanation so far is that this triggers the acoustic reflex, which is usually triggered by speech or loud noises.”
Christopher Fassnidge, from City, University of London, suggested that the gif is an example of synaesthesia – when one sensation in one of the senses, such as hearing, involuntarily triggers another sensation in another sense.
Because synesthetic pairings can be learned when we’re small, Fassnidge told The Verge, it makes sense that people can develop synaesthesia for very common things.
Gif-creator Ollis, who goes by @IamHappyToast on Twitter, told ShortList: “I made the animation back in January 2008 for a weekly image challenge on the satirical digital arts forum b3ta.com.
“I don’t know the science behind why people hear a noise, I just animated it in a way that I thought was funny and looked right.
“I’m a 3D artist/animator based in the UK and have been doing this sort of thing for 25 years.”
And this isn’t the only gif you can hear and feel. Here are a few more examples:
Pretty amazing, really.
(Image: Chris Ollis/@IamHappyToast)