Motion-to-sound synesthesia

It can also be called hearing motion or visually-induced auditory synesthesia

It can be called kinetics-to-sound if it refers to hearing one’s own body movements 

Some people hear silent movements. This can be considered a type of synesthesia, although not in all cases.

There appear to be basically three different manifestations of this phenomenon: hearing GIFs and animations; hearing the silent movements of the elements around us (objects, animals, other people, etc.); and hearing our own body movements on observing them visually or perceiving them through proprioception.

The sounds perceived are simple and basic and usually take the form of clicking, whistling, thudding, droning, ringing, etc.

Here is a description of each type and an explanation of when it should and shouldn’t be considered a type of synesthesia:

1. Hearing GIFs and animations

When is it not synesthesia?

It has been estimated that 25% of the general population regularly have auditory sensations on observing certain silent movements, such as GIF animations or movements watched in a soundless video. Even when there is no sound the brain can “fill in” the missing auditory information, if it is a logical consequence of the moving image being observed. So, for example, when a soundless GIF or video shows someone breaking a window, a little “crash” at a very low volume might be heard at the moment of impact. This “filling in” or “anticipatory” effect cannot be considered synesthesia and is rather the effect of something called the “visually evoked auditory response” (VEAR). There is a link to an article about this phenomenon further on.

Here are two examples of the kind of GIFs many people “hear” without it meaning they have synesthesia:

Policeman

Pylon

An informal study carried out via Twitter by a researcher from Glasgow University received thousands of responses from readers and determined that almost 70% of people were able to hear the skipping (and thumping) electricity pylon.

And when can it be considered synesthesia?

However, there is a small percentage of people who consistently hear all kinds of GIFs, including abstract forms in movement that cannot be associated with any real-life sounds at all. It is possible that automatically and consistently hearing this kind of GIFs is a type of synesthesia. Here’s an example:

Dots

2. Hearing the movements of the elements around us

Automatically and consistently perceiving sounds on seeing the movements of objects, animals etc. around us is considered a type of synesthesia. People who have this type hear sounds when they observe these silent movements, especially when they have some degree of repetition. Some examples would be a bird flying seen through a closed window, or a flag waving in the wind at a distance. Some people also hear flashing lights.

3. Hearing your own body movements

When is it not synesthesia?

Some people have auditory sensitivity to certain biological processes, such as their heartbeat or the blood flowing through their veins. Some of them hear their eyes blink or hear their neck when they turn their head. There are physical causes for these phenomena that are not related to synesthesia.

And when can it be considered synesthesia?

What could be considered a type of synesthesia is hearing silent movements of parts of the body, such as bending your arm or waving your hands, just by looking at them. In this case the sound would be perceived on actually seeing the action: if there was no visual stimulus no sound would be heard.

Other people have a type of synesthesia where they hear their body movements not by seeing them visually but by merely perceiving them through proprioception, i.e. sensing what position they are in and how their body is moving. This does not mean internal bodily processes but kinetic movements such as bending their knee, wiggling their toes or fingers, lifting their arm, etc. Little is known about these types of synesthesia – if they really are synesthesia – and there are few studies on them. They seem to be infrequent: in Sean Day's study it was found that only 1% of the 1,143 synesthetes interviewed reported having kinetics-to-sound experiences.

Here are some descriptions written by people with these possible types of synesthesia:

“I watch my cat walk across the floor. His legs “schwoot” and his paws “top top” and his tail “hums” from side to side. Example 2: I am in yoga class, we are doing shoulder rolls. My neighbor’s motion sounds like like an industrial machine of some kind... “WoooOOO... woooOOO.” Most sounds are machine-like in fact.”

(Source: This post on Reddit/Synesthesia. 2020.)

"Strobe light, deafening, if they’re going fast enough the noise is going to get loud enough to blind me, it’s like a fuzzy white out when it happens.”

(Source: This comment on Reddit/Synesthesia. 2020.)

"For the longest time I’ve heard sounds to seeing and feeling movement. This is especially true for my own moving body but can be heard mentally watching other people or things move.

For instance, if I take a step to grab a cup from a cupboard, I hear my leg, body, arm and fingers as they twist extend and contract. Almost as if I was a robot with rusty joints. And depending on the movement/speed/and limb it’s a different pitch that rises and falls. As different parts are moving I hear them simultaneously. (...)

I’ve always been a bit fascinated with dancers. Not sure exactly why. Maybe it’s because the sound of their movements matches the actual sound and it’s like a strange reverb effect where everything is in sync.”

(Source: This post and comment on Reddit/Synesthesia. 2020.)

“I can hear touch (...).

Well, "hear" in a sense. I can’t actually hear it as if the sound were playing in real life, but the sound plays in the back of my head. I knew about this my entire life, but I really started to think about it recently. For example, every time I touch one of my fingers to my thumb it plays a high or low pitch sound, depending on which finger. Almost like a piano. But it's more noticeable with movement. When I see something move but it makes no noise, my brain fills in the silence with a sound. Everything has its own sound, but it's usually not the sound it'd make if it wasn’t silent.”

(Source: This post on Reddit/Do I Have Synesthesia. 2021.)

Some links:

Here’s an interesting article on the “visually evoked auditory response” (VEAR) and the skipping and thumping electricity pylon phenomenon.

Here’s an ongoing research study on hearing GIFs you can participate in.

Concept-sound synesthesia

Another type of synesthesia, much less common but possibly related, involves perceiving sounds, pitches or musical notes in response to concepts that do not necessarily move but which form part of a group, series or sequence. Some synesthetes report auditory reactions to different shapes, time units, graphemes, colours, people or even hairstyles!

Go to the page on Concept-sound synesthesia

This page last updated: 08 December 2022