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Updated: Aug 14, 2026
11:51
Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making
Published on: March 2, 2011
Estrogenic encounters: how interactions between aromatase and the environment modulate aggression
Brian C Trainor1, Helen H Kyomen, Catherine A Marler
1Department of Psychology, Ohio State University, Columbus, 43210, USA. bctrainor@gmail.com
Frontiers in Neuroendocrinology
|December 27, 2005
Summary
Estrogen, not just testosterone, influences aggression by acting within the brain. Social experiences can alter brain estrogen levels, impacting aggressive behavior across species.
Area of Science:
- Neuroendocrinology
- Behavioral Neuroscience
- Comparative Psychology
Background:
- Aggression research initially focused on testosterone (T), but studies show inconsistent links between peripheral T and aggression.
- Inconsistencies may arise from T metabolism in the brain, particularly conversion to estrogen via aromatase.
- Estrogen's role in modulating aggression is increasingly recognized, independent of androgenic pathways.
Purpose of the Study:
- To review and integrate findings on estrogen's role in aggression across diverse species.
- To compare mechanisms of estrogen action on aggression in birds, mammals, and humans.
- To explore how social experiences influence central estrogen production and aggressive behavior.
Main Methods:
- Comparative literature review of studies on aggression in birds, mammals, and humans.
- Analysis of hormonal mechanisms, focusing on testosterone, estrogen, aromatase, and estrogen receptors.
- Examination of the interplay between social experience, neuroendocrinology, and aggressive behavior.
Main Results:
- Estrogen, via aromatase and estrogen receptors in the brain, significantly modulates aggressive behavior across species.
- Social experiences can alter brain estrogen levels, influencing aggression independently of peripheral testosterone.
- Species-specific differences exist in how estrogen modulates aggression, suggesting diverse evolutionary adaptations.
Conclusions:
- Estrogen is a key neuroendocrine regulator of aggression, acting centrally.
- Social factors interact with neuroendocrine pathways to shape aggressive behavior.
- An integrative, comparative approach is crucial for understanding the complex mechanisms underlying aggression.
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