title: Optogenetic Stimulation of Lateral Amygdala Input to Posterior Piriform Cortex Modulates Single-Unit and Ensemble Odor Processing.
abstract: Olfactory information is synthesized within the olfactory cortex to provide not only an odor percept, but also a contextual significance that supports appropriate behavioral response to specific odor cues. The piriform cortex serves as a communication hub within this circuit by sharing reciprocal connectivity with higher processing regions, such as the lateral entorhinal cortex and amygdala. The functional significance of these descending inputs on piriform cortical processing of odorants is currently not well understood. We have employed optogenetic methods to selectively stimulate lateral and basolateral amygdala (BLA) afferent fibers innervating the posterior piriform cortex (pPCX) to quantify BLA modulation of pPCX odor-evoked activity. Single unit odor-evoked activity of anesthetized BLA-infected animals was significantly modulated compared with control animal recordings, with individual cells displaying either enhancement or suppression of odor-driven spiking. In addition, BLA activation induced a decorrelation of odor-evoked pPCX ensemble activity relative to odor alone. Together these results indicate a modulatory role in pPCX odor processing for the BLA complex. This interaction could contribute to learned changes in PCX activity following associative conditioning, as well as support alternate patterns of odor processing that are state-dependent.
authors.affiliation: Department of Child and Adolescent Psychiatry, NYU School of Medicine, NYU Langone Medical Center, New YorkNY, USA; The Emotional Brain Institute, The Nathan S. Kline Institute for Psychiatric Research, OrangeburgNY, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Sadrian
authors.affiliation: Department of Child and Adolescent Psychiatry, NYU School of Medicine, NYU Langone Medical Center, New YorkNY, USA; The Emotional Brain Institute, The Nathan S. Kline Institute for Psychiatric Research, OrangeburgNY, USA.
authors.forename: Donald A
authors.initials: DA
authors.lastname: Wilson
mesh_terms: D000200:Action Potentials; D000344:Afferent Pathways / Q000502:physiology; D000818:Animals; D066272:Basolateral Nuclear Complex / Q000502:physiology*; D000229:Dependovirus / Q000235:genetics; D005260:Female; D005822:Genetic Vectors; D008297:Male; D008810:Mice, Inbred C57BL; D009812:Odorants; D055696:Olfactory Perception / Q000502:physiology*; D062308:Optogenetics / Q000379:methods; D010812:Physical Stimulation / Q000379:methods; D066195:Piriform Cortex / Q000502:physiology*
keywords: basolateral amygdala; channelrhodopsin; fear conditioning; odor coding; optogenetics; piriform cortex; top–down processing