Sound from Left or Right?
Why are two ears better than one?Copyright US Department of Veteran's Affairs http://www.warrelatedillness.va.gov/education/healthconditions/hearing-difficulties.asp
Why do humans have two ears? How do the properties of sound help with directional hearing? Students learn about directional hearing and how our brains determine the direction of sounds by the difference in time between arrival of sound waves at our right and left ears. Student pairs use experimental set-ups that include the headset portions of stethoscopes to investigate directional hearing by testing each other's ability to identify the direction from which sounds originate.
Biological engineers and neuroscientists perceive human bodies as functioning, controlled systems, not unlike robots. Research is increasingly revealing that mathematical principles similar to those used in robotics are extremely useful or even necessary for a complete understanding of the human body. Engineers use their understanding of the benefits of having two ears and how they help us determine the direction of origins of sounds to design technologies such as radar systems.
After this activity, students should be able to:
- Describe how having two ears makes it possible to determine the direction of origin of sounds (binaural hearing).
- Describe the situation in the experimental set-up in which listeners cannot detect the direction of sounds.