'Fearful-place' coding in the amygdala-hippocampal network
- University of Washington, United States
- Korea University of Science & Technology, Republic of Korea
- Catholic Kwandong University, Republic of Korea
- Ewha Womans University, Republic of Korea
Abstract
Animals seeking survival needs must be able to assess different locations of threats in their habitat. However, the neural integration of spatial and risk information essential for guiding goal-directed behavior remains poorly understood. Thus, we investigated simultaneous activities of fear-responsive basal amygdala (BA) and place-responsive dorsal hippocampus (dHPC) neurons as rats left the safe nest to search for food in an exposed space and encountered a simulated 'predator'. In this realistic situation, BA cells increased their firing rates and dHPC place cells decreased their spatial stability near the threat. Importantly, only those dHPC cells synchronized with the predator-responsive BA cells remapped significantly as a function of escalating risk location. Moreover, optogenetic stimulation of BA neurons was sufficient to cause spatial avoidance behavior and disrupt place fields. These results suggest a dynamic interaction of BA's fear signalling cells and dHPC's spatial coding cells as animals traverse safe-danger areas of their environment.
Data availability
The data that support the findings of this study are available under the project DOI https://doi.org/10.5061/dryad.2z34tmpn0. The customized analysis tools are deposited on Github https://github.com/KimLab-UW?tab=repositories.
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BA-dHPC simultaneous recordingDryad Digital Repository, doi:10.5061/dryad.2z34tmpn0.
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Customized analysis toolsPublicly available at Github (https://github.com).
Article and author information
Author details
Funding
National Institute of Mental Health (MH088073)
- Jeansok John Kim
National Research Foundation of Korea (NRF-2015M3C7A1028392)
- Jeiwon Cho
National Research Foundation of Korea (NRF-2019R1A2C2088377)
- Jeiwon Cho
National Research Foundation of Korea (NRF-2018M3C7A1024736)
- Yeowool Huh
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 in this study were performed in strict compliance with the University of Washington Institutional Animal Care and Use Committee guidelines (protocol #0404-01). Animals were individually housed in a climate-controlled vivarium (accredited by the Association for Assessment and Accreditation of Laboratory Animal Care) with thorough daily health checkup. Surgeries were performed under ketamine and xylazine mixture anesthesia to minimize physical discomfort, and post-operative assessments for injury, distress, and pain were followed.
Copyright
© 2021, Kong 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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'Fearful-place' coding in the amygdala-hippocampal network
eLife 10:e72040.
https://doi.org/10.7554/eLife.72040
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