Cargando…

An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains

The hippocampal system contains neural populations that encode an animal's position and velocity as it navigates through space. Here, we show that such populations can embed two codes within their spike trains: a firing rate code (R) conveyed by within‐cell spike intervals, and a co‐firing rate...

Descripción completa

Detalles Bibliográficos
Autores principales: Grgurich, Ryan, Blair, Hugh T.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley & Sons, Inc. 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7154697/
https://www.ncbi.nlm.nih.gov/pubmed/32065487
http://dx.doi.org/10.1002/hipo.23197
_version_ 1783521874591875072
author Grgurich, Ryan
Blair, Hugh T.
author_facet Grgurich, Ryan
Blair, Hugh T.
author_sort Grgurich, Ryan
collection PubMed
description The hippocampal system contains neural populations that encode an animal's position and velocity as it navigates through space. Here, we show that such populations can embed two codes within their spike trains: a firing rate code (R) conveyed by within‐cell spike intervals, and a co‐firing rate code ([Formula: see text]) conveyed by between‐cell spike intervals. These two codes behave as conjugates of one another, obeying an analog of the uncertainty principle from physics: information conveyed in R comes at the expense of information in [Formula: see text] , and vice versa. An exception to this trade‐off occurs when spike trains encode a pair of conjugate variables, such as position and velocity, which do not compete for capacity across R and [Formula: see text]. To illustrate this, we describe two biologically inspired methods for decoding R and [Formula: see text] , referred to as sigma and sigma‐chi decoding, respectively. Simulations of head direction and grid cells show that if firing rates are tuned for position (but not velocity), then position is recovered by sigma decoding, whereas velocity is recovered by sigma‐chi decoding. Conversely, simulations of oscillatory interference among theta‐modulated “speed cells” show that if co‐firing rates are tuned for position (but not velocity), then position is recovered by sigma‐chi decoding, whereas velocity is recovered by sigma decoding. Between these two extremes, information about both variables can be distributed across both channels, and partially recovered by both decoders. These results suggest that populations with different spatial and temporal tuning properties—such as speed versus grid cells—might not encode different information, but rather, distribute similar information about position and velocity in different ways across R and [Formula: see text]. Such conjugate coding of position and velocity may influence how hippocampal populations are interconnected to form functional circuits, and how biological neurons integrate their inputs to decode information from firing rates and spike correlations.
format Online
Article
Text
id pubmed-7154697
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher John Wiley & Sons, Inc.
record_format MEDLINE/PubMed
spelling pubmed-71546972020-04-14 An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains Grgurich, Ryan Blair, Hugh T. Hippocampus Research Articles The hippocampal system contains neural populations that encode an animal's position and velocity as it navigates through space. Here, we show that such populations can embed two codes within their spike trains: a firing rate code (R) conveyed by within‐cell spike intervals, and a co‐firing rate code ([Formula: see text]) conveyed by between‐cell spike intervals. These two codes behave as conjugates of one another, obeying an analog of the uncertainty principle from physics: information conveyed in R comes at the expense of information in [Formula: see text] , and vice versa. An exception to this trade‐off occurs when spike trains encode a pair of conjugate variables, such as position and velocity, which do not compete for capacity across R and [Formula: see text]. To illustrate this, we describe two biologically inspired methods for decoding R and [Formula: see text] , referred to as sigma and sigma‐chi decoding, respectively. Simulations of head direction and grid cells show that if firing rates are tuned for position (but not velocity), then position is recovered by sigma decoding, whereas velocity is recovered by sigma‐chi decoding. Conversely, simulations of oscillatory interference among theta‐modulated “speed cells” show that if co‐firing rates are tuned for position (but not velocity), then position is recovered by sigma‐chi decoding, whereas velocity is recovered by sigma decoding. Between these two extremes, information about both variables can be distributed across both channels, and partially recovered by both decoders. These results suggest that populations with different spatial and temporal tuning properties—such as speed versus grid cells—might not encode different information, but rather, distribute similar information about position and velocity in different ways across R and [Formula: see text]. Such conjugate coding of position and velocity may influence how hippocampal populations are interconnected to form functional circuits, and how biological neurons integrate their inputs to decode information from firing rates and spike correlations. John Wiley & Sons, Inc. 2020-02-17 2020-04 /pmc/articles/PMC7154697/ /pubmed/32065487 http://dx.doi.org/10.1002/hipo.23197 Text en © 2020 The Authors. Hippocampus published by Wiley Periodicals, Inc. This is an open access article under the terms of the http://creativecommons.org/licenses/by/4.0/ License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
spellingShingle Research Articles
Grgurich, Ryan
Blair, Hugh T.
An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains
title An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains
title_full An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains
title_fullStr An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains
title_full_unstemmed An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains
title_short An uncertainty principle for neural coding: Conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains
title_sort uncertainty principle for neural coding: conjugate representations of position and velocity are mapped onto firing rates and co‐firing rates of neural spike trains
topic Research Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7154697/
https://www.ncbi.nlm.nih.gov/pubmed/32065487
http://dx.doi.org/10.1002/hipo.23197
work_keys_str_mv AT grgurichryan anuncertaintyprincipleforneuralcodingconjugaterepresentationsofpositionandvelocityaremappedontofiringratesandcofiringratesofneuralspiketrains
AT blairhught anuncertaintyprincipleforneuralcodingconjugaterepresentationsofpositionandvelocityaremappedontofiringratesandcofiringratesofneuralspiketrains
AT grgurichryan uncertaintyprincipleforneuralcodingconjugaterepresentationsofpositionandvelocityaremappedontofiringratesandcofiringratesofneuralspiketrains
AT blairhught uncertaintyprincipleforneuralcodingconjugaterepresentationsofpositionandvelocityaremappedontofiringratesandcofiringratesofneuralspiketrains