Modeling of neuronal networks through experimental decomposition

The studies reviewed experimental procedures which attempted to eliminate anatomical connections between dentate granule cells and progressively increasing numbers of other populations of cells belonging to the hippocampus. The objectives were to identify response dynamics intrinsic to dentate granule cells and to determine, at least qualitatively, the extent to which those intrinsic dynamics are modified by other populations of hippocampal neurons normally interconnected with granule cells. Nonlinear response characteristics of granule cells, when examined in relative isolation, were qualitatively different from nonlinearities expressed by the same population of neurons when interacting with other elements of the hippocampal system. This indicates that the influence of the network on functional characteristics of one of its elements can be substantial. It is also found that the use of relatively standard procedures for preparing in vitro slices of central nervous system tissue may allow a close approximation of open-loop conditions for major cell populations of mammalian neural systems