Abstract The olfactory bulb is an excellent model system for the study of sensory neurophysiology and neural information coding. Many lines of evidence indirectly suggest that spatial patterning of activity in the olfactory bulb is important for encoding olfactory information, but the relationship between the spatial patterns of activity in the bulb and olfactory stimulus space remain to be fully elucidated. Lateral inhibition in sensory systems is related to the stimulus space of the sensory modality. In the glomerular layer of the olfactory bulb, lateral inhibitory interactions between glomeruli are primarily mediated by short axon cells. This proposal expands on previous work demonstrating that interglomerular inhibition is sparse and selective to directly test possible mechanisms for this specificity. Two hypotheses relating to specificity of odor evoked inhibition are examined through optical recordings of activity from the output neurons of the olfactory bulb, mitral and tufted cells, and from short axon cells. This project will characterize the functional and spatial properties of interglomerular inhibition by stimulating olfactory activity with odors and optogenetic techniques. The results of these experiments will yield new insight into the role of interglomerular inhibition and the short axon cell network.