Sparse coding of birdsong and receptive field structure in songbirds
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2009Citation:
Garrett Greene, David Barrett, Kamal Sen and Conor Houghton, Sparse coding of birdsong and receptive field structure in songbirds, Network: Computation in Neural Systems, 20, 3, 2009, 162 - 177Download Item:
Abstract:
Auditory neurons can be characterized by a spectro-temporal receptive field, the kernel of a linear
filter model describing the neuronal response to a stimulus. With a view to better understanding the
tuning properties of these cells, the receptive fields of neurons in the zebra finch auditory fore-brain
are compared to a set of artificial kernels generated under the assumption of sparseness; that is, the
assumption that in the sensory pathway only a small number of neurons need be highly active at any
time. The sparse kernels are calculated by finding a sparse basis for a corpus of zebra-finch songs.
This calculation is complicated by the highly-structured nature of the songs and requires
regularization. The sparse kernels and the receptive fields, though differing in some respects, display
several significant similarities, which are described by computing quantative properties such as the
seperability index and Q-factor. By comparison, an identical calculation performed on human speech
recordings yields a set of kernels which exhibit widely different tuning. These findings imply that
Field L neurons are specifically adapted to sparsely encode birdsong and supports the idea that
sparsification may be an important element of early sensory processing.
Sponsor
Grant Number
Science Foundation Ireland
Author's Homepage:
http://people.tcd.ie/houghtcjhttp://people.tcd.ie/barretda
http://people.tcd.ie/greenegt
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Network: Computation in Neural Systems20
3
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sparse kernels, birdsongMetadata
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