Sniffing can be initiated by dopamine’s actions on ventral striatum neurons

Abstract

Sniffing is a motivated behavior displayed by all terrestrial vertebrates on the planet. While sniffing is associated with acquiring and processing odors, sniffing is also intertwined with affective and motivated states. The neuromodulatory systems which influence the display of sniffing are unclear. Here, we report that dopamine release into the ventral striatum, with exception of the nucleus accumbens core, is coupled with bouts of sniffing and that stimulation of dopaminergic terminals in those regions initiates sniffing. The activity of post-synaptic D1 and D2 receptor-expressing neurons in the ventral striatum is also coupled with sniffing and antagonism of ventral striatum D1 and D2 receptors squelches sniffing behavior. Together, these results support a model whereby sniffing is initiated by dopamine’s actions upon ventral striatum neurons. The nature of sniffing being integral to both olfaction and motivated behaviors implicates this circuit in a wide array of functions.One-Sentence SummaryMesolimbic dopamine input to the ventral striatum supports the highly conserved behavior of sniffing by promoting both the initiation and vigor of sniffing bouts.