The most practiced performers make little mistakes, even after repeating something a thousand times. You could write off these subtle variations as just system noise, proof that muscles aren’t machines. But a California research team has a different idea. They propose that such mistakes could be part of a trial and error procedure that continually improves performance. Their findings appear in the December 20 issue of Nature.
The scientists were studying bird song. Bengalese finches, like many birds, use jaunty little ditties like this one to attract a mate. [Finch song clip.] Each song is practiced until it’s almost exactly the same every time. [Finch song clip.]
But the birds can still change their tune. Working one bird at a time, the researchers played some loud white noise every time the bird sang a particular note. If the bird happened to sing that note lower, the scientists kept the noise coming. But if the bird sang the note higher, the noise would stop. Over time, the birds learned that higher is better. [Finch note clip.] And they’d lock in the new pitch. [Higher finch note clip.] If only the females would take a liking to this melodious mistake, Bengalese finches might soon be singing a whole new song.