What do you hear when you see this .gif from a transmission tower "jump rope"? If you are a majority, you hear that the tower lands every time it jumps over the power line.
Does anyone in visual perception know why you can hear this gif? pic.twitter.com/mcT22Lzfkp
– Lisa DeBruine ?️? (@lisadebruine) December 2, 2017
This whole discussion started earlier this week when Dr. Lisa DeBruine from the Institute of Neuroscience & Psychology at the University of Glasgow published the .gif on Twitter. He then conducted a survey on how many people had an audible reaction and, from the time of publication, most hear a "thud".
Happy Toast responsible for creating the .gif file, discovered that the "sound" that some people listen to is not necessarily linked to the towers:
The thud is almost totally messed up, if you crop the pylons themselves you can still hear it. They simply give it height. pic.twitter.com/3LZK1g24yZ
– HappyToast ★ (@IamHappyToast) December 4, 2017
So, why do some people hear noise while others do not?
Dr. DeBruine told the BBC he does not know why some people listen to him, while others feel it and others do not perceive anything. "Some people who are deaf and hard of hearing have reported the three perceptions, as well as people with aphantasia" (a lack of visual images).
He adds: "I thought some of the sight scientists that I follow [on Twitter] could explain immediately, but there seem to be several plausible explanations and no clear consensus."
But there is one person whose reaction to the Twitter thread was quite useful. Chris Fassnidge, a doctoral candidate in psychology at City University in London, tells the BBC that he suspects that the phenomenon is related to the auditory response evoked visually.
This is the ability of some people to hear moving objects even though they do not emit a sound, which can be a subtle form of synesthesia, the unleashing of one sense by another.
We are constantly surrounded by movements that produce a sound, whether it be steps while people walk, lip movements while talking, ball bouncing in the playground, or shock when we drop a glass.
The final answer to why only some people have this ability to "hear" silent objects is not yet clear. Fassnidge says that it is what determines who experiences vEAR and how intensely "probably individual differences are in the way our brain is connected".