A goal of many audiologists and scientists is to figure how a human or any mammal for that matter understands the location of sounds. This type of research is crucial for creating the best versions of hearing aids and assistive listening devices possible. Research has given scientists answers on how people figure out what direction a sound is coming from, but there was one piece of the puzzle missing. How do people understand how far away a sound is from where they are located?
This question has remained a mystery to researchers and audiologists for quite some time. Researchers at UConn Health have release a new report in the Journal of Neuroscience that sheds light on the mystery of how we know how far away sounds are. They suggest that we use echoes and fluctuations in volume to understand the amount of distance between where we are standing and where the noise origin is located. This is known as the third dimension of sound location. The researchers, Duck O. Kim and Shigeyuki Kuwada looked to test their theory about sound and distance on rabbits first and later in humans. They recorded the sounds from inside the ear when a pre-recorded modulated and unmodulated sound was played from multiple locations. Next they looked at how the midbrain- or region responsible for understanding sound responded. They found when studying the rabbits hearing response certain neurons fired more when the mammal heard certain sounds were closer and at a higher modulation. As the sounds got further away, the more echoes came into effect as they degrade amplitude modulation. In lay-mans terms the further away a sound is, the more it bounces off our surroundings due to echoes and the more something echoes, the further away it is from us. Our brain responds differently to noises and echoes and that is what this research has shed light on for researchers. They hope to continue their research surround this topic to tie together how the perception of distance as well as horizontal and vertical directions of sounds are all connected.
Stay up to date on the latest in hearing loss news at KSAudiology.com. We are a full service hearing loss treatment center with multiple location throughout western New York. Find out more about the types of hearing loss treatments available by contacting us today.
