Control of parallel hippocampal output pathways by amygdalar long-range inhibition
Abstract
Projections from the basal amygdala (BA) to the ventral hippocampus (vH) are proposed to provide information about the rewarding or threatening nature of learned associations to support appropriate goal-directed and anxiety-like behaviour. Such behaviour occurs via the differential activity of multiple, parallel populations of pyramidal neurons in vH that project to distinct downstream targets, but the nature of BA input and how it connects with these populations is unclear. Using channelrhodopsin-2-assisted circuit mapping in mice, we show that BA input to vH consists of both excitatory and inhibitory projections. Excitatory input specifically targets BA- and nucleus accumbens-projecting vH neurons, and avoids prefrontal cortex-projecting vH neurons; while inhibitory input preferentially targets BA-projecting neurons. Through this specific connectivity, BA inhibitory projections gate place-value associations by controlling the activity of nucleus accumbens-projecting vH neurons. Our results define a parallel excitatory and inhibitory projection from BA to vH that can support goal-directed behaviour.
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Article and author information
Author details
Funding
Wellcome Trust (109360/Z/15/Z)
- Andrew F MacAskill
Wellcome Trust (215165/Z/18/Z)
- Karyna Mishchanchuk
Wellcome Trust (222292/Z/20/Z)
- Jessica Passlack
King Fahad Medical City
- Rawan AlSubaie
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments were approved by the U.K. Home Office as defined by the Animals (ScientificProcedures) Act, and University College London ethical guidelines.
Reviewing Editor
- Marco Capogna, University of Aarhus, Denmark
Version history
- Received: October 15, 2021
- Accepted: November 29, 2021
- Accepted Manuscript published: November 30, 2021 (version 1)
- Version of Record published: December 8, 2021 (version 2)
Copyright
© 2021, AlSubaie 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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