A new study conducted by researchers from Macquarie University, has shown that the brain processes the noisy environment of our planet, explaining why animals, including humans, can easily cope with the silence of morning parks and bustling cafes and streets. The researchers found that as soon as the sound environment becomes familiar auditory neurons, they accelerate the adaptation to the noise level in the environment.
"I wonder how neurons adapt: adaptation takes place as soon as the sound environment becomes familiar. Once the neurons encounter with the surrounding sound environment five or six times, they are able to adapt to two times faster than when they meet a new environment for the first time. This process we call "meta-adaptation" - said Professor David McAlpine, author of the study.
The results indicate that the animal's ability to adapt to different environment noise level is more complex than previously thought, and explains why some people find it difficult to penetrate into the conversation in a noisy environment.
"This phenomenon is known as" hidden hearing loss. " The discovery that the brain learns and adapts to different sound environment to help cope with this common problem of communication, "- explains Professor McAlpine.
In the study, researchers measured the neural response in guinea pigs, because their hearing range similar to the human. Experiments have shown that part of the brain kept sound memories far longer than anticipated due to the feedback loop. Researchers have shown a previously unknown link between the midbrain and the auditory cortex.
"We found that the average brain - the part of the body, which is believed to store information only for a few hundred milliseconds - in fact, the information that he learned about how the environment sounds for several minutes, making it possible to auditory neurons undergo a process meta-adaptation. When we blocked it, the neurons can not adapt, "- concluded Professor McAlpine.