According to the words of Wolfgang Welsh: if vision is a sense of distancing, then sound is a sense of connection. It builds the relationship between our body and the space.
Hearing has a lot to do with our navigation in space. Thinking about sound is always connected to space and its acoustic character. Thanks to our stereo hearing we can locate sound sources, determine the size of a room, the distance to objects, map where we are and simply navigate through our surroundings. Hearing is closely linked to the sense of proprioception, but also to balance and echolocation.

See more: Body perception of sound
in: Non sonic sound

Let’s begin with signal and noise, both of which are represented by sound. What’s the difference?
Signal is simply the sound we decide to focus on and noise is anything else. Our hearing has this special feature of sound filtering. It lets us shift our attention from signal to signal on a wide field of noise. All sound is noise until we decide what is signal, and that’s the difference between hearing and listening. We hear the noise, but when we filter specific sound source then hearing becomes listening. Hearing is passive, listening is active. Listening is selective, while hearing is a continuous experience.

NOTE:
Some of us are constantly experiencing the continuous listening mode though. The hearing of some people on the autism spectrum and small children works in a different way – not only do they hear, but also actively listen to all the sounds happening in their surrounding. Just imagine all of the noise being signal. Sounds like a nightmare audio stimuli overload? It’s important to remember that some of us have to deal with it on a daily basis.

We don’t have eyelids for ears. In listening we are vulnerable. But does ear really never sleep? Let’s just take an everyday morning example – our alertness to sound during sleep makes it possible to wake up with the sound of the alarm. But our brain also registers sound during sleep – this interesting fact is supported by a 2018 scientific study by the Acoustic Society of America. They monitored children’s brains using EEG during both sleep and wakefulness playing them a set of non-existing words during the nap. Later their brains’ responses were measured while listening to the same words mixed with new words when the children were awake. The study showed that the children’s brains were able to recognise the words they heard while they were asleep, indicating that the human brain retains the information that we hear while we sleep.

Locating sound primarily relies on timing. As sound travels different distances to each of our ears, we perceive slight time differences, enabling us to determine the source’s location. This stereo hearing mechanism compares properties like intensity, arrival time, phase, and frequency. When both ears detect equal sound, we perceive it as being in front or behind. This ability to locate sound away from the center is achieved through relative differences in sound. Hearing abilities in animals are influenced by their habitats. Tree-dwelling anthropoids, from which humans descended, had cup-shaped ears for three-dimensional sound localization. In contrast, plains-dwelling animals with pointed ears on top excel at locating sound in the horizontal plane.

Sound doesn’t just place us within a physical environment; it also defines and characterises it. It forms an integral part of our surroundings, offering a vivid depiction. Sound brings life and energy to our overall perception of the world dynamizing our visual encounters. When auditory and visual stimuli synchronize harmoniously, we gain a complete and immersive understanding of reality. Conversely, any situation where sound and image fall out of sync is uncommon and disrupts our natural human experience. Like when you’re watching a movie and there’s a delay in the sound. Not just frustrating, but most of all sensory confusing.

Sound is like a messenger, carrying all sorts of sonic messages. It’s not just about verbal communication – the spatial properties of sound enable the effective transmission of various forms of audio information.
We all know those beeps and buzzes our phones make. All of those alerts and notifications are the modern kind of sound messages we’re all familiar with. But there’s more to it. Sound can tell us a lot about what’s happening around us. Just think of church bells serving as timekeepers, providing an auditory indication of the current hour, train whistles, or sound signals at pedestrian crossing. They all have a social meaning and give us cues about what’s going on.

And language? Well, it’s not just about words either. We all use various auditory non-verbal messages, but here’s an interesting fact: throughout history, people have developed whistled languages that can transmit all sorts of messages over long distances. It’s pretty impressive how whistlers can understand each other and communicate complex informations through whistles.

Sound itself carries a multitude of messages that provide valuable information about the surrounding space.The way sound bounces off surfaces can reveal a lot about the environment we’re in. While we all rely on this type of sonic information, its significance is particularly important for individuals with visual impairments. They use sound to navigate and understand their surroundings. They can figure out where walls, furniture, and even hills or forests are, just by listening to the sound bouncing back to them. It’s like a message in its own way, telling us about the world around us.