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Identification of striatal cell assemblies suitable for reinforcement learning

Both in vivo [1] and in vitro [2] experimental data suggest that medium spiny neurons in striatum participate in the formation of sequentially firing cell assemblies, at a timescale relevant for the presumed involvement of basal ganglia in reinforcement learning. Computational models argue that such cell assemblies are a feature of a minimal network architecture of the striatum [3]. This suggests that cell assemblies can be a potential candidate for representation of the 'system states' in the framework of reinforcement learning.

Spike patterns associated with cells assemblies can be identified by clustering the spectrum of zero-lag cross-correlation between all pairs of neurons in a network [3]. Other methods based on the dimensionality reduction of the similarity matrix of the spike trains have also been used [2, 4].

Here we investigate how the identification of cell assemblies is dependent on the methodology chosen, and to what extent the statistical properties of the cell assemblies make them suitable for representation of system states in the striatum during reinforcement learning.


  1. Miller BR, Walker AG, Shah AS, Barton SJ, Rebec GV: Disregulated information processing by medium spiny neurons in striatum of freely behaving mouse models of Huntington's disease. J Neurophysiol. 2008, 100: 2205-2216. 10.1152/jn.90606.2008.

    Article  PubMed Central  PubMed  Google Scholar 

  2. Carrillo-Reid L, Tecuapetla F, Tapia D, Hernández-Cruz A, Galarraga E, Drucker-Colin R, Bargas J: Encoding network states by striatal cell assemblies. J Neurophysiol. 2008, 99: 1435-1450. 10.1152/jn.01131.2007.

    Article  PubMed  Google Scholar 

  3. Ponzi A, Wickens J: Sequentially switching cell assemblies in random inhibitory networks of spiking neurons in the striatum. J Neurosci. 2010, 30 (17): 5894-5911. 10.1523/JNEUROSCI.5540-09.2010.

    Article  CAS  PubMed  Google Scholar 

  4. Sasaki T, Matsuki N, Ikegaya Y: Metastability of active CA3 networks. J Neurosci. 2007, 27 (3): 517-528. 10.1523/JNEUROSCI.4514-06.2007.

    Article  CAS  PubMed  Google Scholar 

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Partially funded by the German Federal Ministry of Education and Research (BMBF 01GQ0420 to BCCN Freiburg, BMBF GW0542 Cognition and BMBF 01GW0730 Impulse Control), EU Grant 269921 (BrainScaleS), Helmholtz Alliance on Systems Biology (Germany), Neurex, the Junior Professor Program of Baden-Württemberg and the Erasmus Mundus Joint Doctoral programme EuroSPIN.

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Correspondence to Carlos Toledo-Suárez.

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This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Toledo-Suárez, C., Yim, M.Y., Kumar, A. et al. Identification of striatal cell assemblies suitable for reinforcement learning. BMC Neurosci 12 (Suppl 1), P228 (2011).

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