>From Wired News
http://www.wired.com/wiredscience/2010/11/song-bird-language/
Text follows:
The notoriously complex song of the finch has finally succumbed to statisti=
cs. Physicists have developed a model that can map out and predict the note=
s birds sing in sequence.
The new model is roughly eight times more accurate than previous attempts t=
o unravel complex bird songs. If the scientists can use the same technique =
to map and predict chatter in other social animals, they could find importa=
nt clues about the neural origins of complex language, including that of hu=
mans.
"We want to gain an understanding of this simplest case, then work our way =
up in complexity," said physicist Dezhe Jin of Penn State University who le=
d the research, posted Nov. 12 on arXiv.org.
Birdsong originates at the top of a bird's brain in an area called the HVC,=
or higher vocal center, which is made up of about 40,000 neurons. Networks=
of thousands of individual neurons there are thought to generate syllables=
, and these neural networks link up to other areas of the brain to actually=
vocalize the sounds.
Mapping the sounds and their sequence in a song may help resolve such langu=
age-centric brain pathways.
"We think it's like a domino effect, where one syllable cascades into the n=
ext to create complex songs," Jin said. "But before neural coordinates can =
be verified, we need to have robust statistical maps."
Jin stuck a Bengalese finch in a soundproof room for six days with a microp=
hone. The bird tweeted more than 25,000 times, sounds that Jin and his team=
divvied up into 25 groups based on statistical similarity. In total, the f=
inch sang seven distinct song syllables (sounds made very quickly one after=
the other) and 14 other types of notes.
Unlike previous models, which skyrocket in error when trying to predict mor=
e than one note in sequence, the new model factors in the order of previous=
notes. It also takes into account the fact that different neural networks =
may produce the same syllable which, Jin says, provides a subtle but crucia=
l detail in correctly mapping and predicting a song's syllables.
No model will ever be able to predict a bird's song with 100 percent accura=
cy because they improvise as they go, like jazz musicians, Jin said. But th=
ey may be able to get close enough to begin to understand what's happening =
in the bird's brain.
"This is really the beginning of finding how song and language structure or=
iginates," Jin says. "We want to further study other species and apply that=
knowledge to humans."
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