The neurobiology of insect olfaction: Sensory processing in a comparative context

Department of Neuroscience, College of Science, University of Arizona, 1040 East Fourth Street, Tucson, AZ 85721-0077, USA.
Progress in Neurobiology (Impact Factor: 9.99). 09/2011; 95(3):427-47. DOI: 10.1016/j.pneurobio.2011.09.007
Source: PubMed


The simplicity and accessibility of the olfactory systems of insects underlie a body of research essential to understanding not only olfactory function but also general principles of sensory processing. As insect olfactory neurobiology takes advantage of a variety of species separated by millions of years of evolution, the field naturally has yielded some conflicting results. Far from impeding progress, the varieties of insect olfactory systems reflect the various natural histories, adaptations to specific environments, and the roles olfaction plays in the life of the species studied. We review current findings in insect olfactory neurobiology, with special attention to differences among species. We begin by describing the olfactory environments and olfactory-based behaviors of insects, as these form the context in which neurobiological findings are interpreted. Next, we review recent work describing changes in olfactory systems as adaptations to new environments or behaviors promoting speciation. We proceed to discuss variations on the basic anatomy of the antennal (olfactory) lobe of the brain and higher-order olfactory centers. Finally, we describe features of olfactory information processing including gain control, transformation between input and output by operations such as broadening and sharpening of tuning curves, the role of spiking synchrony in the antennal lobe, and the encoding of temporal features of encounters with an odor plume. In each section, we draw connections between particular features of the olfactory neurobiology of a species and the animal's life history. We propose that this perspective is beneficial for insect olfactory neurobiology in particular and sensory neurobiology in general.

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    • " 2008 ; Yamagata et al . , 2009 ; Brandstaetter and Kleineidam , 2011 ; Dacks and Nighorn , 2011 ; Rössler and Zube , 2011 ; Nishikawa et al . , 2012 ; Brill et al . , 2013 ; Carcaud et al . , 2015 ) . In the long run the knowledge gained from these studies might be transferred to insects with different tract layouts ( Galizia and Rössler , 2010 ; Martin et al . , 2011 ) and thus promote a more fundamental understanding of olfactory guided behavior ."
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