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Transforming neural computations and representing time

Hopfield, J. J. (1996) Transforming neural computations and representing time. Proceedings of the National Academy of Sciences of the United States of America, 93 (26). pp. 15440-15444. ISSN 0027-8424. PMCID PMC26423. doi:10.1073/pnas.93.26.15440.

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Motifs of neural circuitry seem surprisingly conserved over different areas of neocortex or of paleocortex, while performing quite different sensory processing tasks. This apparent paradox may be resolved by the fact that seemingly different problems in sensory information processing are related by transformations (changes of variables) that convert one problem into another. The same basic algorithm that is appropriate to the recognition of a known odor quality, independent of the strength of the odor, can be used to recognize a vocalization (e.g., a spoken syllable), independent of whether it is spoken quickly or slowly. To convert one problem into the other, a new representation of time sequences is needed. The time that has elapsed since a recent event must be represented in neural activity. The electrophysiological hallmarks of cells that are involved in generating such a representation of time are discussed. The anatomical relationships between olfactory and auditory pathways suggest relevant experiments. The neurophysiological mechanism for the psychophysical logarithmic encoding of time duration would be of direct use for interconverting olfactory and auditory processing problems. Such reuse of old algorithms in new settings and representations is related to the way that evolution develops new biochemistry.

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Additional Information:© 1996 National Academy of Sciences. Contributed by J. J. Hopfield, October 7, 1996. I thank Alan Gelperin for a critical reading of multiple drafts of the manuscript. The research was supported in part by the National Science Foundation’s Engineering Research Center at the California Institute of Technology. The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked ‘‘advertisement’’ in accordance with 18 U.S.C. §1734 solely to indicate this fact.
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Caltech Engineering Research CenterUNSPECIFIED
Subject Keywords:olfaction; audition; representation; sequences
Issue or Number:26
PubMed Central ID:PMC26423
Record Number:CaltechAUTHORS:20141203-110316015
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Official Citation:J. J. Hopfield Transforming neural computations and representing time PNAS 1996 93 (26) 15440-15444
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:52326
Deposited By: Tony Diaz
Deposited On:03 Dec 2014 20:34
Last Modified:10 Nov 2021 19:24

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