How sound builds and shapes our world By Orna Herr, Communications Officer at the British Science Association ------------------------ Being told to picture a beautiful beach with waves crashing, seeing a video of the beach with no audio, or just listening to the sound of the waves; which do you think would be the most evocative of the experience of being on a beach? This was an experiment musician and sound artist James Andean conducted with the audience at ‘Stories of sound’, his talk at the British Science Festival. He found, and the audience agreed, that it is the sound often helps us place ourselves in situ the most. So what is it about sound that can be so powerful, that it can work alone as a storyteller and world-builder, helping hearing people* connect with their environment in a way that other senses might not? A detailed picture James explained that while sound brings people information about the source of the sound and its location which is “essential to us to navigating our environment”, it also provides a second, simultaneous message: Sound brings us information about the path that that sound took between its source and my ear. And what objects or elements that sound encountered along that path. In other words, the sound brings us information not just about the sound itself but about the sound’s environment and by extension, about my own environment. We might not always realise it, but our brain is processing data at lightning speed to feed us information. He offers the example of a dog running through a hall, barking. Our brain senses that the sound took a fraction longer to reach one ear than the other, so we can determine the direction of the sound is coming from, and so where the dog is. We can also determine “with pinpoint accuracy the trajectory that that dog was taking [while running], all through sound”. Staying with the dog, James explained that as the sound of barks hit surfaces in the room, those surfaces would leave a trace on that sound, absorbing its energy or deflecting it at a certain angle. This means that by the time that sound reaches our ears, it’s laden with a dossier of data that, for many of us, our conscious minds aren’t fully aware of. The unconscious mind It can be easy to think that vision is the primary way we perceive our environment, and of course it plays an enormous role. But James highlighted the limitations of vision from which sound does not suffer. We cannot see behind us; vision offers us just a slice of our environment whereas sound draws a detailed image from every angle. James shared a story of working on a film as a sound recordist where he followed a sightless woman and her guide dog as she narrated her surroundings through sounds. She was walking along a canal, noticing lampposts along the path at regular intervals through the sound of her footsteps reflecting off them, until she passed one which had a lifejacket hooked onto it. She stopped and identified, through a change in the behaviour of sound, that there was an object on the lamppost that hadn’t been on the previous ones. She was able to ‘hear’ its size, shape and location, touch helped her recognise it as a lifejacket. “We tend to think of this as a kind of superpower that is the acquired by the sightless. That for the blind that their powers of hearing somehow improves dramatically in order to make up for the loss of sight,” he said. “But what does that actually mean?” Biologically, we all have the same apparatus, working in the same way. “So in fact we are receiving all of that same information all the time. We are processing it and we are using it get around [just like sightless people], the only difference is…we’re not consciously aware of it.” Sighted people don’t need to use sound information consciously to navigate their surroundings, whereas sightless people do need to be conscious of the information it carries. And so, the brain rewires to allow for that. Sound and loneliness Sound is so effective at helping us place ourselves with our environment - its 360 degree nature placing us at the centre of it - that when sounds are distorted or masked it can affect our psyche. Cities are often considered lonely and isolating places, despite being so full of people. James posits that the constant blanket of noise caused mostly by traffic is obscuring the more subtle sound cues which help hearing people place themselves in their environment and connect with it. “By imposing this noise floor on us in cities, we’re effectively severing ourselves from our environment, including severing ourselves from all these people that surround us. We’re cut off from the information we need to place ourselves in that environment and so we’re cut off from the environment.” The soundwaves that hit our ears offer us a detailed image of our environment which we can interpret through our unique perceptions of what certain noises mean to us. (James also conducted an experiment during his British Science Festival event in which the audience closed their eyes, were played some sounds, and were asked what they heard. The responses to one noise were as varied as a bird and a supermarket trolley). If we stop to listen, we can experience the world in a deeper way. *First person collective pronouns will be used hereafter to refer to hearing people, as this blog relates to sound, but we acknowledge that deaf and hard of hearing people would have different experiences.