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Sequence Disambiguation by Functionally Divided Hippocampal CA3 Model

  • Toshikazu Samura
  • Motonobu Hattori
  • Shun Ishizaki
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4232)

Abstract

Many sequences are acquired in the hippocampus. Sequences are represented by a series of events which are associative representations of information and they are linked with each other by common representations. The sequences must, however, be recalled individually, even if the sequences are overlapped at some representations: otherwise we couldn’t retrieve own precious memory correctly. Therefore, sequence disambiguation is an essential function to separate the overlapped sequences. In this study, we focus on the location dependencies of the hippocampal CA3 region which are obtained from very detailed anatomical findings of the CA3 and the physiological findings of Spike-Timing Dependent Plasticity (STDP), and suggest that the CA3 is functionally divided by its location dependencies. Moreover, we show that functionally divided CA3 could generate a code for sequence disambiguation by using computer simulations. Finally, we also suggest that the sequence disambiguation can be realized between the CA3 and the hippocampal CA1 region.

Keywords

Dentate Gyrus Entorhinal Cortex Synaptic Weight Location Dependency Theta Wave 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Toshikazu Samura
    • 1
  • Motonobu Hattori
    • 2
  • Shun Ishizaki
    • 1
  1. 1.Graduate School of Media and GovernanceKeio UniversityKanagawaJapan
  2. 2.Interdisciplinary Graduate School of Medicine and EngineeringUniversity of YamanashiYamanashiJapan

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