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Updated: May 21, 2026
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Stress-Enhanced Fear Learning, a Robust Rodent Model of Post-Traumatic Stress Disorder
Published on: October 13, 2018
Epigenetic mechanisms in learned fear: implications for PTSD
1Department of Neurobiology, Evelyn F. McKnight Brain Institute, University of Alabama, Birmingham, AL 35294-2182, USA.
Summary
Experience drives lasting behavioral changes by altering gene expression in the central nervous system (CNS). Epigenetic mechanisms, like DNA methylation, are key to forming memories such as fear conditioning, potentially offering new PTSD treatments.
Area of Science:
- Neuroscience
- Molecular Biology
- Behavioral Science
Background:
- Learning and memory involve lasting functional and behavioral changes.
- Experience actively alters gene expression in the central nervous system (CNS).
- Epigenetic mechanisms regulate gene transcription in the CNS.
Purpose of the Study:
- Review data supporting the role of epigenetic mechanisms in long-term behavioral change.
- Hypothesize that DNA methylation and demethylation drive gene transcription in the CNS.
- Explore the link between epigenetic mechanisms and fear conditioning.
Main Methods:
- Review of existing studies on gene expression and behavior.
- Analysis of data on epigenetic regulation in the CNS.
- Examination of animal models of fear conditioning.
Main Results:
- Epigenetic mechanisms, particularly DNA methylation/demethylation, actively regulate CNS gene transcription.
- These mechanisms are crucial for forming and stabilizing fear conditioning in the hippocampus and amygdala.
- Evidence from animal studies supports this hypothesis.
Conclusions:
- Epigenetic molecular mechanisms drive long-term behavioral changes via CNS gene transcription.
- These mechanisms are implicated in fear conditioning, relevant to post-traumatic stress disorder (PTSD).
- Epigenetically-based pharmacotherapy may offer novel treatments for PTSD.
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