Encoding and Retrieval in a CA1 Microcircuit Model of the Hippocampus

  • Vassilis Cutsuridis
  • Stuart Cobb
  • Bruce P. Graham
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5164)


Recent years have witnessed a dramatic accumulation of knowledge about the morphological, physiological and molecular characteristics, as well as connectivity and synaptic properties of neurons in the mammalian hippocampus. Despite these advances, very little insight has been gained into the computational function of the different neuronal classes; in particular, the role of the various inhibitory interneurons in encoding and retrieval of information remains elusive. Mathematical and computational models of microcircuits play an instrumental role in exploring microcircuit functions and facilitate the dissection of operations performed by diverse inhibitory interneurons. A model of the CA1 microcircuitry is presented using biophysical representations of its major cell types: pyramidal, basket, axo-axonic, bistratified and oriens lacunosum-moleculare cells. Computer simulations explore the biophysical mechanisms by which encoding and retrieval of spatio-temporal input patterns are achieved by the CA1 microcircuitry. The model proposes functional roles for the different classes of inhibitory interneurons in the encoding and retrieval cycles.


Hippocampus CA1 microcircuit computer model pyramidal cell basket cell bistratified cell axo-axonic cell OLM cell STDP 


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  1. 1.
    Andersen, P., Morris, R., Amaral, D., Bliss, T., O’Keefe, J.: The hippocampus book. Oxford University press, Oxford (2007)Google Scholar
  2. 2.
    Freund, T.F., Buzsaki, G.: Interneurons of the hippocampus. Hippocampus 6, 347–470 (1996)CrossRefGoogle Scholar
  3. 3.
    Eichenbaum, H., Dunchenko, P., Wood, E., Shapiro, M., Tanila, H.: The hippocampus, memory and place cells: is it spatial memory or a memory of space? Neuron 23(2), 209–226 (1999)CrossRefGoogle Scholar
  4. 4.
    Baude, A., Bleasdale, C., Dalezios, Y., Somogyi, P., Klausberger, T.: Immunoreactivity for the GABAA receptor α1 subunit, somatostatin and connexion36 distinguishes axoaxonic, basket and bistratified interneurons of the rat hippocampus. Cerebral Cortex 17(9), 2094–2107 (2007)CrossRefGoogle Scholar
  5. 5.
    Cutsuridis, V., Hunter, R., Cobb, S., Graham, B.P.: Storage and Recall in the CA1 Microcircuit of the Hippocampus: A Biophysical Model. In: Sixteenth Annual Computational Neuroscience Meeting CNS 2007, Toronto, Canada, July 8th - 12th, 2007, vol. 8 (Suppl 2), p. 33. BMC Neuroscience (2007)Google Scholar
  6. 6.
    Graham, B.P., Cutsuridis, V.: Dynamical Information Processing in the CA1 Microcircuit of the Hippocampus. In: Computational Modeling in behavioral neuroscience: Closing the gap between neurophysiology and behavior. Psychology Press, Taylor and Francis Group, London (December 2008) (to be published)Google Scholar
  7. 7.
    Hasselmo, M., Bodelon, C., Wyble, B.: A proposed function of the hippocampal theta rhythm: separate phases of encoding and retrieval of prior learning. Neural. Comput. 14, 793–817 (2002)zbMATHCrossRefGoogle Scholar
  8. 8.
    Hines, M.L., Carnevale, T.: The NEURON simulation environment. Neural. Comput. 9, 1179–1209 (1997)CrossRefGoogle Scholar
  9. 9.
    Hunter, R., Cutsuridis, V., Cobb, S., Graham, B.: Improving Associative Memory in a Model Network of Two-Compartment Spiking Neurons. In: Fourth Annual Scottish Neuroscience Group Meeting, University of Edinburgh (August 31, 2007)Google Scholar
  10. 10.
    Klausberger, T., Magill, P.J., Marton, L.F., David, J., Roberts, B., Cobden, P.M., Buzsaki, G., Somogyi, P.: Brain-state- and cell-type-specific firing of hippocampal interneurons in vivo. Nature 421, 844–848 (2003)CrossRefGoogle Scholar
  11. 11.
    Klausberger, T., Marton, L.F., Baude, A., Roberts, J.D., Magill, P.J., Somogyi, P.: Spike timing of dendrite-targeting bistratified cells during hippocampal network oscillations in vivo. Nat. Neurosci. 7(1), 41–47 (2004)CrossRefGoogle Scholar
  12. 12.
    Kunec, S., Hasselmo, M.E., Kopell, N.: Encoding and retrieval in the CA3 region of the hippocampus: a model of theta-phase separation. J. Neurophysiol. 94(1), 70–82 (2005)CrossRefGoogle Scholar
  13. 13.
    Leung, L.S., Roth, L., Canning, K.J.: Entorhinal inputs to hippocampal CA1 and dentate gyrus in the rat: a current-source-density study. J. Neurophys. 73(6), 2392–2403 (1995)Google Scholar
  14. 14.
    Menschik, E.D., Finkel, L.H.: Neuromodulatory control of hippocampal function: towards a model of Alzheimer’s disease. Artificial Intelligence in Medicine 13, 99–121 (1998)CrossRefGoogle Scholar
  15. 15.
    Paulsen, O., Moser, E.: A model of hippocampal memory encoding and retrieval: GABAergic control of synaptic plasticity. TINS 21, 273–279 (1998)Google Scholar
  16. 16.
    Poirazzi, P., Brannon, T., Mel, B.W.: Arithmetic of subthreshold synaptic summation in a model CA1 pyramidal cell. Neuron 37, 977–987 (2003a)CrossRefGoogle Scholar
  17. 17.
    Poirazzi, P., Brannon, T., Mel, B.W.: Pyramidal neuron as a 2-layer neural network. Neuron 37, 989–999 (2003)CrossRefGoogle Scholar
  18. 18.
    Santhakumar, V., Aradi, I., Soltetz, I.: Role of mossy fiber sprouting and mossy cell loss in hyperexcitability: a network model of the dentate gyrus incorporating cells types and axonal topography. J. Neurophysiol. 93, 437–453 (2005)CrossRefGoogle Scholar
  19. 19.
    Saraga, F., Wu, C.P., Zhang, L., Skinner, F.K.: Active dendrites and spike propagation in multicompartmental models of oriens-lacunosum/moleculare hippocampal interneurons. J. Physiol. 552(3), 673–689 (2003)CrossRefGoogle Scholar
  20. 20.
    Brun, V.H., Otnass, M.K., Molden, S., Steffenach, H.A., Witter, M.P., Moser, M.B., Moser, E.I.: Place cells and place recognition maintained by direct entorhinal-hippocampal circuitry. Science 296, 2243–2246 (2002)CrossRefGoogle Scholar
  21. 21.
    Sommer, F.T., Wennekers, T.: Associative memory in networks of spiking neurons. Neural Networks 14, 825–834 (2001)CrossRefGoogle Scholar
  22. 22.
    Song, S., Miller, K., Abbott, L.: Competitive ”hebbian” learning through spike-timing-dependent synaptic plasticity. Nat. Neurosci. 3, 919–926 (2000)CrossRefGoogle Scholar
  23. 23.
    Wallestein, G.V., Hasselmo, M.E.: GABArgic modulation of hippocampal population activity: sequence learning, place field development and the phase precession effect. J. Neurophys. 78, 393–408 (1997)Google Scholar
  24. 24.
    Megias, M., Emri, Z.S., Freund, T.F., Gulyas, A.I.: Total number and distribution of inhibitory and excitatory synapses on hippocampal CA1 pyramidal cells. Neuroscience 102(3), 527–540 (2001)CrossRefGoogle Scholar
  25. 25.
    Gulyas, A.I., Megias, M., Emri, Z., Freund, T.F.: Total number and ration of excitatory and inhibitory synapses converging onto single interneurons of different types in the CA1 area of the rat hippocampus. J. Neurosci. 19(22), 10082–10097 (1999)Google Scholar
  26. 26.
    Amaral, D., Lavenex, P.: Hippocampal neuroanatomy. In: Andersen, P., Morris, R., Amaral, D., Bliss, T., O’Keefe, J. (eds.) The Hippocampus Book, pp. 37–114. Oxford University press, Oxford (2007)Google Scholar
  27. 27.
    Buhl, E.H., Halasy, K., Somogyi, P.: Diverse sources of hippocampal unitary inhibitory postsynaptic potentials and the number of synaptic release sites. Nature 368, 823–828 (1994a)CrossRefGoogle Scholar
  28. 28.
    Buhl, E.H., Han, Z.S., Lorinczi, Z., Stezhka, V.V., Kapnup, S.V., Somogyi, P.: Physiological properties of anatomically identified axo-axonic cells in the rat hippocampus. J. Neurophys. 71(4), 1289–1307 (1994b)Google Scholar
  29. 29.
    Somogyi, P., Klausberger, T.: Defined types of cortical interneurons structure space and spike timing in the hippocampus. J. Physiol. 562(1), 9–26 (2005)CrossRefGoogle Scholar
  30. 30.
    Migliore, M., Hoffman, D.A., Magee, J.C., Johnston, D.: Role of an A-type K +  conductance in the back-propagation of action potentials in the dendrites of hippocampal pyramidal neurons. J. Comp. Neurosci. 7, 5–15 (1999)zbMATHCrossRefGoogle Scholar
  31. 31.
    O’Reilly, R.C., McClelland, J.L.: Hippocampal conjunctive encoding, storage, and recall: avoiding a trade-off. Hippocampus 4(6), 661–682 (1994)CrossRefGoogle Scholar
  32. 32.
    Stuart, G., Spruston, N.: Determinants of voltage attenuation in neocortical pyramidal neuron dendrites. J. Neurosci. 18(10), 3501–3510 (1998)Google Scholar
  33. 33.
    Bi, G.Q., Poo, M.M.: Synaptic modifications in cultured hippocampal neurons: dependence on spike timing, synaptic strength and postsynaptic cell type. J. Neurosci. 18, 10464–10472 (1998)Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Vassilis Cutsuridis
    • 1
  • Stuart Cobb
    • 2
  • Bruce P. Graham
    • 1
  1. 1.Department of Computing Science and MathematicsUniversity of StirlingStirlingU.K.
  2. 2.Division of Neuroscience and Biomedical SystemsUniversity of GlasgowGlasgowU.K.

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