Imagine you're at a party. All around you guests are chatting and music is playing. But you're only interested in hearing the person next to you. Fortunately, the brain is equipped with mechanisms that help to tune out this background noise and allow us to focus on specific sounds. Yet very little is known about how this actually works. These traces show how a ferret's hearing system – surprisingly similar to our own – responds to speech in an increasingly noisy environment (top to bottom). The coloured traces on the left represent the sound itself, while the other peaks are patterns of nerve activity in different parts of the brain that process sound. They reveal that the background noise gets 'tuned out' gradually as the signals get closer to the main part of the brain (furthest right), revealing more about how we cope with noisy situations.
Written by Kat Arney
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