title: PLACE CELLS. Autoassociative dynamics in the generation of sequences of hippocampal place cells.
abstract: Neuronal circuits produce self-sustaining sequences of activity patterns, but the precise mechanisms remain unknown. Here we provide evidence for autoassociative dynamics in sequence generation. During sharp-wave ripple (SWR) events, hippocampal neurons express sequenced reactivations, which we show are composed of discrete attractors. Each attractor corresponds to a single location, the representation of which sharpens over the course of several milliseconds, as the reactivation focuses at that location. Subsequently, the reactivation transitions rapidly to a spatially discontiguous location. This alternation between sharpening and transition occurs repeatedly within individual SWRs and is locked to the slow-gamma (25 to 50 hertz) rhythm. These findings support theoretical notions of neural network function and reveal a fundamental discretization in the retrieval of memory in the hippocampus, together with a function for gamma oscillations in the control of attractor dynamics.
authors.affiliation: Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Brad E
authors.initials: BE
authors.lastname: Pfeiffer
authors.affiliation: Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA. david.foster@jhu.edu.
authors.forename: David J
authors.initials: DJ
authors.lastname: Foster
mesh_terms: D000818:Animals; D065818:Gamma Rhythm; D006624:Hippocampus / Q000166:cytology* / Q000502:physiology*; D008297:Male; D011939:Mental Recall / Q000502:physiology*; D009434:Neural Pathways; D009474:Neurons / Q000502:physiology*; D051381:Rats; D020332:Rats, Inbred LEC