Frontiers in Systems Neuroscience Systems Neuroscience

Abstract

underlying chemosensory coding and learning in this moth species (Kvello et al., 2009). Like for all fi ve insect brain atlases, the ALs are included as a single brain compartment without internal structures. Different from the other atlases, the AL of the H. virescens brain atlas includes exclusively the glomerular layer as a single labelled identity, an advantage for registering the AL glomeruli as separate units into the atlas. Numerous studies have been devoted to the neuronal network of the primary olfactory centres, the olfactory bulb in vertebrates and the AL in insects, in trying to elucidate how olfactory information is processed and coded (Laurent et al. Common for the two systems are the input elements of sensory neurons, the output elements of mitral/tufted cells and projection neurons (PNs) respectively, intrinsic local interneurons, as well as centrifugal modulatory neurons. Typical are the numerous glomeruli, spheric-ovoid structures of fi ne neuropils with condensations of synapses forming a neuronal network; in insects between all four elements. Each glomerulus represents a functional unit receiving information from one set of sensory neurons with the same receptor protein type and sending out the processed information to olfactory areas of higher order