title: Iterated function systems in the hippocampal CA1.
abstract: How does the information of spatiotemporal sequence stemming from the hippocampal CA3 area affect the postsynaptic membrane potentials of the hippocampal CA1 neurons? In a recent study, we observed hierarchical clusters of the distribution of membrane potentials of CA1 neurons, arranged according to the history of input sequences (Fukushima et al Cogn Neurodyn 1(4):305-316, 2007). In the present paper, we deal with the dynamical mechanism generating such a hierarchical distribution. The recording data were investigated using return map analysis. We also deal with a collective behavior at population level, using a reconstructed multi-cell recording data set. At both individual cell and population levels, a return map of the response sequence of CA1 pyramidal cells was well approximated by a set of contractive affine transformations, where the transformations represent self-organized rules by which the input pattern sequences are encoded. These findings provide direct evidence that the information of temporal sequences generated in CA3 can be self-similarly represented in the membrane potentials of CA1 pyramidal cells.
authors: Research Institute for Electronic Science, Hokkaido University, Kita-20, Nishi-10, Kita-ku, Sapporo, 001-0020, Japan, kuroda@math.sci.hokudai.ac.jp.
authors: Shigeru
authors: S
authors: Kuroda
authors: Yasuhiro
authors: Y
authors: Fukushima
authors: Yutaka
authors: Y
authors: Yamaguti
authors: Minoru
authors: M
authors: Tsukada
authors: Ichiro
authors: I
authors: Tsuda