Subcortico-amygdala pathway processes innate and learned threats
- Aarhus University, Denmark
Abstract
Behavioral flexibility and timely reactions to salient stimuli are essential for survival. The subcortical thalamic-basolateral amygdala (BLA) pathway serves as a shortcut for salient stimuli ensuring rapid processing. Here, we show that BLA neuronal and thalamic axonal activity mirror the defensive behavior evoked by an innate visual threat as well as an auditory learned threat. Importantly, perturbing this pathway compromises defensive responses to both forms of threats, in that animals fail to switch from exploratory to defensive behavior. Despite the shared pathway between the two forms of threat processing, we observed noticeable differences. Blocking beta-adrenergic receptors impair the defensive response to the innate but not the learned threats. This reduced defensive response, surprisingly, is reflected in the suppression of the activity exclusively in the BLA, as the thalamic input response remains intact. Our side-by-side examination highlights the similarities and differences between innate and learned threat-processing, thus providing new fundamental insights.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file; source data for all the figures are deposited at Dyrad and available at https://doi.org/10.5061/dryad.dbrv15f54The codes generated for this work are available on GitHub at https://github.com/NabaviLab-Git/Photometry-Signal-Analysis
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Distinct representations of innate and learned threats within the thalamic-amygdala pathwayDryad Digital Repository, doi:10.5061/dryad.dbrv15f54.
Article and author information
Author details
Funding
Danish Council for Independent Research
- Sadegh Nabavi
Novo Nordisk (NNF16OC0023368)
- Sadegh Nabavi
AUFF NOVA
- Sadegh Nabavi
Danish Research Institute of Translational Neuroscience (19958)
- Sadegh Nabavi
The Danish National Research Foundation (DNRF133)
- Sadegh Nabavi
ERC starting grant (22736)
- Sadegh Nabavi
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 the animal expermentations performed here were reviewed and approved by Danish Animal Experiment Inspectorate (permit number 2020-15-0201-00421)
Copyright
© 2023, Khalil 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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Subcortico-amygdala pathway processes innate and learned threats
eLife 12:e85459.
https://doi.org/10.7554/eLife.85459
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