Role of centrifugal projections to the olfactory bulb in olfactory processing

Abstract

While there is evidence that feedback projections from cortical and neuromodulatory structures to the olfactory bulb are crucial for maintaining the oscillatory dynamics of olfactory bulb processing, it is not clear how changes in dynamics are related to odor perception. Using electrical lesions of the olfactory peduncle, sparing output from the olfactory bulb while decreasing feedback inputs to the olfactory bulb, we demonstrate here a role for feedback inputs to the olfactory bulb in the formation of odor–reward associations, but not for maintaining primary bulbar odor representations, as reflected by spontaneous odor discrimination.

Nonlinear effects of noradrenergic modulation of olfactory bulb function in adult rodents

“…This apparent difference in the bulbar role across tasks has been observed in a number of experiments. For example, habituation memory was not affected by broad lesions of feedback to the MOB from central structures, whereas learning of a reward-motivated discrimination was (Kiselycznyk et al 2006). In contrast, blockade of cholinergic receptors in the MOB, individual or global, only affected habituation memory but not discrimination learning in a reward-motivated task (Chaudhury et al 2009;Linster et al 2001;Mandairon et al 2006a).…”

Arc-Expressing Neuronal Ensembles Supporting Pattern Separation Require Adrenergic Activity in Anterior Piriform Cortex: An Exploration of Neural Constraints on Learning

“…The data also imply that feedback from the learned aPC representation is necessary to the development of stability in the OB ensemble. Odor/reward associations are slowed when centrifugal feedback to the bulb is transected (Kiselycznyk et al, 2006). Blockade of OB NE does not prevent stability or pattern separation changes in aPC ensembles, but slows their appearance.…”

A computer-assisted odorized hole-board for testing olfactory perception in mice

“…In the field of olfaction, there has been explosive growth over the past decade in the understanding of the behavioral consequences of network modulation (Kaba and Keverne, 1988;Ravel et al, 1994;Sullivan and Wilson, 1994;Linster et al, 2001;Mandairon et al, 2006bMandairon et al, ,c, 2008bKiselycznyk et al, 2006;Doucette et al, 2007;Guerin et al, 2008) as well as the consequences of learning on the neural network (Gray et al, 1986;Kay et al, 1996;Kay and Laurent, 1999;Buonviso and Chaput, 2000;Rochefort et al, 2002;Spors and Grinvald, 2002;Fletcher and Wilson, 2003;Martin et al, 2004Martin et al, , 2006Alonso et al, 2006;Mandairon et al, 2006aMandairon et al, , 2008bWoo et al, 2007;Beshel et al, 2007). This explains the growing interest for behavioral research into olfaction in mice.…”