Exclusive noise Exclusive noise
2005/09/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria
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The fish Porichthys notatus is able to make noise and at the same time hear sounds from the outside. In fact, few fish produce sounds, but their male sprout with crispation to attract the female during the breeding season. It is so noisy that the inhabitants of San Francisco Bay complain that it looks like a submerged engine.
Although the noise causes discomfort to the neighbors, the fish itself does not suffer discomfort. Researchers at the University of Cornell have found that it has a special system to block the sound it emits at the very moment it produces it. In the next millisecond, however, the block is interrupted and is capable of listening to external sounds. Somehow, the auditory block and vocalization are synchronized in the fish's brain.
In the image appears a graph of nervous impulses. The impulses that go to the muscles of the voice appear in yellow, which causes the buzz. However, the sound occurs a little later, between two yellow tips. At that time, the brain sends the signal to the ear of the fish (in the graph in red). By means of this signal, the ear is blocked at the time of sound emission.
![](https://elia.eus/static/elhuyar/img/elia_RGB.png)