Our sense of hearing is incredibly important. It helps us to communicate, and it helps our brain build a picture of the world around us.
For example, if a sound we’re familiar with is louder, then we would generally perceive it to be closer. A loud car horn might make us jump and look around for danger, but we wouldn’t react in the same way to a quieter, more muffled ‘beep’ as it’s much more likely to belong to a car further down the street.
As well as understanding our immediate environment, our brain’s perception of sound also affects our perception of our own bodies.
In a recent study by Ana Tajadura-Jiménez et al. participants listened to their footsteps through headphones as they walked on a wooden surface. As they walked, the sound of their footsteps were distorted. The sounds the participants heard through the headphones corresponded to the sound a lighter or heavier body would make.
In general, the distorted footsteps changed the participants' sense of their own body weight. Participants especially reported that the higher frequency footsteps led to the perception of being thinner.
When trying the test out for herself New Scientist reporter Corrinne Burns said “In a matter of seconds, I experience a sensation of lightness in my lower legs.”
This video summarizes the research:
Researcher Chris Jack has also played with this concept in a similar experiment. Highly sensitive microphones were attached to long rods worn to pick up sounds well above the heads of the participants as they walked along a gravel path. The microphones relayed the sounds of the environment from these ‘extendable ears’ directly to headphones. Participants generally reported feeling very tall and found it more difficult to judge distances. For example, the sound of a car at the end of the path felt much closer.
Corrinne Burns explains what’s going on:
“These experiments suggest that we carry a mental model of our body.”
“This model is then constantly updated with sensory information from the outside world, and from special receptors inside the body that sense the movement and position of joints and muscles – called proprioceptors.”
doppel’s Expert Psychologist Manos Tsakiris has also spoken of the importance of our sense of hearing when it comes to building a picture of our bodies.
“Sound is a fundamental yet under-investigated dimension of body representations. For hearing people, there is a continuous, ever-present soundtrack to our bodily actions.”
Now we might not all have access to sensitive microphones but we think that the insight these experiments give are interesting nonetheless.