Odor-Modulated Collective Network Oscillations of Olfactory Interneurons in a Terrestrial Mollusc

Determination of the dynamical structure of neural circuits is a necessary prerequisite to understanding their computational function (Tank, 1989). Rhythmically active or oscillating neural circuits are particularly interesting dynamical structures, since rhythms and oscillations are a prominent feature of mammalian CNS electrophysiology. Coherent oscillations by networks of interneurons are observed in the vertebrate olfactory system (Freeman, 1975; Shepherd, 1985) and have recently been described in mammalian visual cortex (Gray and Singer, 1989; Gray et al, 1989; Eckhorn et al. , 1988a, b). These interneuronal networks display oscillations in local field potential (LFP) and probability of producing action potentials that are reported to be highly correlated between subcircuits sharing the same stimulus features.