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Aggression in humans: what is its biological foundation?
D J Albert1, M L Walsh, R H Jonik
1Psychology Department, University of British Columbia, Vancouver, Canada.
Neuroscience and Biobehavioral Reviews
|January 1, 1993
Summary
Human aggression is not driven by testosterone levels as commonly believed. Instead, it shares more similarities with defensive aggression found in mammals, suggesting different biological roots.
Area of Science:
- Neuroscience
- Behavioral Biology
- Endocrinology
Background:
- Human aggression is often inaccurately linked to testosterone levels, mirroring nonprimate mammalian models.
- Existing research shows inconsistent correlations between testosterone and human aggression across various conditions.
Purpose of the Study:
- To investigate the biological underpinnings of human aggression.
- To determine if human aggression aligns with testosterone-dependent aggression or defensive aggression in mammals.
Main Methods:
- Review of existing literature on testosterone levels and aggression in humans.
- Comparison of human aggression characteristics with testosterone-dependent and defensive aggression models in nonprimate mammals.
- Analysis of aggression changes related to hormonal fluctuations, puberty, and neuropathology.
Main Results:
- Serum testosterone levels do not consistently differentiate high- and low-aggression individuals.
- Aggression does not correlate with testosterone changes during puberty, hypogonadism, or in cases of hirsutism.
- Human aggression aligns with defensive aggression, showing consistency across ages and sexes, and correlating with specific neural activity (hypothalamus, amygdala).
Conclusions:
- Human aggression's biological basis is more closely related to defensive aggression mechanisms observed in nonprimate mammals.
- The common inference of testosterone-driven human aggression lacks substantial empirical support.
- Neurological factors, rather than testosterone, appear to play a more significant role in human aggression.
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