Neural mechanisms of social learning in the female mouse
Abstract
Social interactions are often powerful drivers of learning. In female mice, mating creates a long-lasting sensory memory for the pheromones of the stud male that alters neuroendocrine responses to his chemosignals for many weeks. The cellular and synaptic correlates of pheromonal learning, however, remain unclear. We examined local circuit changes in the accessory olfactory bulb (AOB) using targeted ex vivo recordings of mating-activated neurons tagged with a fluorescent reporter. Imprinting led to striking plasticity in the intrinsic membrane excitability of projection neurons (mitral cells, MCs) that dramatically curtailed their responsiveness, suggesting a novel cellular substrate for pheromonal learning. Plasticity selectively targeted the MC ensembles activated by the stud male, consistent with formation of memories for specific individuals. Finally, MC excitability gained atypical activity-dependence whose slow dynamics strongly attenuated firing on timescales of several minutes. This unusual form of AOB plasticity may act to filter sustained or repetitive sensory signals.
Article and author information
Author details
Funding
National Institute on Deafness and Other Communication Disorders (DC013894)
- Ian G Davison
Klingenstein Third Generation Foundation (n/a)
- Ian G Davison
Binational Science Foundation (2015099)
- Ian G Davison
Binational Science Foundation (2013314)
- Ian G Davison
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Naoshige Uchida, Harvard University, United States
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#14-034) of Boston University.
Version history
- Received: January 26, 2017
- Accepted: June 13, 2017
- Accepted Manuscript published: June 16, 2017 (version 1)
- Version of Record published: July 27, 2017 (version 2)
Copyright
© 2017, Gao et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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