MAR 08, 2016 4:42 AM PST

Bats Show How The Brain Filters Noise

It’s a noisy world out there. Whether it’s the sound of traffic, a crowded office with phones ringing and printers clacking, or a busy restaurant, the amount of auditory stimuli in normal every day environments can make it hard to focus. How does the brain filter out the noise we don’t need to hear, and allow in the important noises like a honking horn to alert us to an oncoming car, or a siren that lets us know to give way to an emergency vehicle?
Bats can filter out sounds when navigating
In new research from Johns Hopkins University, published recently the journal Proceedings of the National Academy of Sciences, a team of neuroscientists and biologists looked at how bats determine what sounds they need to pay attention to, and which they can safely ignore or filter out.
 
Bats are nocturnal, hunting at night since more insects are around after sunset and there far less predators. Since there isn’t normally much ambient light, bats are often flying through the air in total darkness. To keep from bashing into trees or other obstacles bats use echolocation to navigate their environment. Much like sonar pings used in submarines, they will chirp as they fly around and those sounds are echoed off  trees, rocks, mountains etc. coming back to them in distinct patterns depending on the surroundings.
 
Bats too have much to discern in these patterns and in other noises. In the research at Johns Hopkins, the team monitored the mid-brain activity of bats to see which sounds would evoke a response and which could be ignored. They played recorded sounds of the bats own chirping noises as well as white noise and other random sounds. All of the sounds were played for the same duration and the same volume. In the mid-brain of bats, all of the sensorimotor neurons reacted to all of the sounds in some way. However, the specific neurons that are involved in stimulus selection and that guide the bats navigation patterns only responded to natural chirping sounds. The white noise and other sounds were effectively ignored by the bats so they could focus on the sounds they needed to guide them.
 
In a press release from Johns Hopkins Department of Psychological and Brain Sciences, lead author for the study Melville J. Wohlgemuth said,  “With so many stimuli in the world, the brain needs a filter to determine what’s important. The bat brain has developed special sensitivities that allow it to pick out sounds from the environment that are pertinent to the animal. We were able to uncover these sensitivities because we used the perfect stimulus — the bat’s own vocalizations.”
 
Check out the video below to see more about the study and how bat echolocation might show us how the human brain filters noise to stay focused.
 
About the Author
  • I'm a writer living in the Boston area. My interests include cancer research, cardiology and neuroscience. I want to be part of using the Internet and social media to educate professionals and patients in a collaborative environment.
You May Also Like
APR 15, 2020
Neuroscience
APR 15, 2020
How Magic Mushrooms Restructure the Brain
For some time now, researchers have suspected that psilocybin, the hallucinogen chemical present in ‘magic mushroo ...
APR 15, 2020
Cell & Molecular Biology
APR 15, 2020
Sugar's Appeal Lies in a Circuit That Connects the Gut & Brain
New work may help explain why sugar cravings are so hard to satisfy.
APR 19, 2020
Neuroscience
APR 19, 2020
Does Listening to Background Music Reduce Creativity?
Although music has long been thought to enhance creativity, new research says that it may actually have the opposite eff ...
APR 26, 2020
Plants & Animals
APR 26, 2020
Researchers Observe Vocal Learning in Bats
Bats have garnered oodles of attention in previous weeks as they’ve been identified as potential carriers of the i ...
MAY 02, 2020
Immunology
MAY 02, 2020
Cellular "Cleaning Crews" Get Busy During Spinal Cord Injury
  Nerve cells transmit and receive information traversing the human body in the form of electrical impulses. These ...
JUL 02, 2020
Cell & Molecular Biology
JUL 02, 2020
The Intricate Movements of a Critical Receptor are Revealed
Scientists have now learned more about a critical protein in the brain called the NMDA receptor, tracking every atom as ...
Loading Comments...