title: Odor Experience Facilitates Sparse Representations of New Odors in a Large-Scale Olfactory Bulb Model.
abstract: Prior odor experience has a profound effect on the coding of new odor inputs by animals. The olfactory bulb, the first relay of the olfactory pathway, can substantially shape the representations of odor inputs. How prior odor experience affects the representation of new odor inputs in olfactory bulb and its underlying network mechanism are still unclear. Here we carried out a series of simulations based on a large-scale realistic mitral-granule network model and found that prior odor experience not only accelerated formation of the network, but it also significantly strengthened sparse responses in the mitral cell network while decreasing sparse responses in the granule cell network. This modulation of sparse representations may be due to the increase of inhibitory synaptic weights. Correlations among mitral cells within the network and correlations between mitral network responses to different odors decreased gradually when the number of prior training odors was increased, resulting in a greater decorrelation of the bulb representations of input odors. Based on these findings, we conclude that the degree of prior odor experience facilitates degrees of sparse representations of new odors by the mitral cell network through experience-enhanced inhibition mechanism.
authors.affiliation: School of Life Science and The Collaborative Innovation Center for Brain Science, The Center for Computational Systems Biology, Fudan University Shanghai, China.
authors.forename: Shanglin
authors.initials: S
authors.lastname: Zhou
authors.affiliation: Division of Palermo, Institute of Biophysics, National Research CouncilPalermo, Italy; Department of Neurobiology, Yale University School of MedicineNew Haven, CT, USA.
authors.forename: Michele
authors.initials: M
authors.lastname: Migliore
authors.affiliation: School of Life Science and The Collaborative Innovation Center for Brain Science, The Center for Computational Systems Biology, Fudan University Shanghai, China.
authors.forename: Yuguo
authors.initials: Y
authors.lastname: Yu
keywords: large scale network; odor representation; olfactory bulb; prior experience; sparse representation