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Source: http://www.newscientist.com/article/dn23143-musical-brains-smash-audio-algorithm-limits.html
Musical brains smash audio algorithm limits
06 February 2013Devised over 200 years ago, the Fourier transform is a mathematical process that splits a sound wave into its individual frequencies. It is the most common method for digitising analogue signals and some had thought that brains make use of the same algorithm when turning the cacophony of noise around us into individual sounds and voices.
To investigate, Jacob Oppenheim and Marcelo Magnasco of Rockefeller University in New York turned to the Gabor limit, a part of the Fourier transform's mathematics that makes the determination of pitch and timing a trade-off. Rather like the uncertainty principle of quantum mechanics, the Gabor limit states you can't accurately determine a sound's frequency and its duration at the same time.
13 times better
The pair reasoned that if people's hearing obeyed the Gabor limit, this would be a sign that they were using the Fourier transform. But when 12 musicians, some instrumentalists, some conductors, took a series of tests, such as judging slight changes in the pitch and duration of sounds at the same time, they beat the limit by up to a factor of 13.
This shows that the Fourier transform is not the whole story, says Magnasco. "The actual algorithm employed by our brains is still shrouded in mystery."
Brian Moore of the University of Cambridge says he is not surprised that the musicians beat the limit: he already assumed that other mechanisms were at work.
Understanding human sound perception could inspire better systems for sound recordings, speech recognition and sonar.
Journal reference: Physical Review Letters, doi.org/kdw
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"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
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