title: Basal forebrain dynamics during nonassociative and associative olfactory learning.
abstract: Cholinergic and GABAergic projections from the horizontal diagonal band (HDB) and medial preoptic area (MCPO) of the basal forebrain to the olfactory system are associated with odor discrimination and odor learning, as well as modulation of neural responses in olfactory structures. Whereas pharmacological and lesion studies give insights into the functional role of these modulatory inputs on a slow timescale, the response dynamics of neurons in the HDB/MCPO during olfactory behaviors have not been investigated. In this study we examined how these neurons respond during two olfactory behaviors: spontaneous investigation of odorants and odor-reward association learning. We observe rich heterogeneity in the response dynamics of individual HDB/MCPO neurons, with a substantial fraction of neurons exhibiting task-related modulation. HDB/MCPO neurons show both rapid and transient responses during bouts of odor investigation and slow, long-lasting modulation of overall response rate based on behavioral demands. Specifically, baseline rates were higher during the acquisition phase of an odor-reward association than during spontaneous investigation or the recall phase of an odor reward association. Our results suggest that modulatory projections from the HDB/MCPO are poised to influence olfactory processing on multiple timescales, from hundreds of milliseconds to minutes, and are therefore capable of rapidly setting olfactory network dynamics during odor processing and learning.
authors.affiliation: Department of Neurobiology and Behavior, Cornell University, Ithaca, New York; and.
authors.forename: Sasha
authors.initials: S
authors.lastname: Devore
authors.affiliation: Department of Neurobiology and Behavior, Cornell University, Ithaca, New York; and.
authors.forename: Nathaniel
authors.initials: N
authors.lastname: Pender-Morris
authors.affiliation: Department of Neurobiology and Behavior, Cornell University, Ithaca, New York; and.
authors.forename: Owen
authors.initials: O
authors.lastname: Dean
authors.affiliation: Department of Psychology, Cornell University, Ithaca, New York.
authors.forename: David
authors.initials: D
authors.lastname: Smith
authors.affiliation: Department of Neurobiology and Behavior, Cornell University, Ithaca, New York; and cl243@cornell.edu.
authors.forename: Christiane
authors.initials: C
authors.lastname: Linster
mesh_terms: D000200:Action Potentials; D000818:Animals; D001245:Association Learning / Q000502:physiology; D066187:Basal Forebrain / Q000502:physiology*; D004192:Discrimination, Psychological / Q000502:physiology; D007858:Learning / Q000502:physiology*; D008297:Male; D009474:Neurons / Q000502:physiology*; D009812:Odorants; D055696:Olfactory Perception / Q000502:physiology*; D020318:Rats, Long-Evans; D012201:Reward
keywords: GABA; acetylcholine; basal forebrain; electrophysiology; neuromodulation; olfaction