AUTHOR=Kim David H., Chang Andrew Y., McTavish Thomas S., Patel Hetal K., Willhite David C. TITLE=Center-surround vs. distance-independent lateral connectivity in the olfactory bulb JOURNAL=Frontiers in Neural Circuits VOLUME=6 YEAR=2012 URL=https://www.frontiersin.org/journals/neural-circuits/articles/10.3389/fncir.2012.00034 DOI=10.3389/fncir.2012.00034 ISSN=1662-5110 ABSTRACT=

Lateral neuronal interactions are known to play important roles in sensory information processing. A center-on surround-off local circuit arrangement has been shown to play a role in mediating contrast enhancement in the visual, auditory, and somatosensory systems. The lateral connectivity and the influence of those connections have been less clear for the olfactory system. A critical question is whether the synaptic connections between the primary projection neurons, mitral and tufted (M/T) cells, and their main inhibitory interneurons, the granule cells (GCs), can support a center-surround motif. Here, we study this question by injecting a “center” in the glomerular layer of the olfactory bulb (OB) with a marker of synaptic connectivity, the pseudorabies virus (PRV), then examines the distribution of labeling in the “surround” of GCs. We use a novel method to score the degree to which the data fits a center-surround model vs. distance-independent connectivity. Data from 22 injections show that M/T cells generally form lateral connections with GCs in patterns that lie between the two extremes.