Criminal Minds: Hormones & Suspect Behavior

Ted Bundy, Jeffery Dahmer, The Golden State Killer – these are all names associated with some of the most horrific and notorious transgressions known to the modern world. Many criminologists have entirely blamed criminal behavior entirely on social factors like abusive childhood, sexual abuse, parental abandonment, poverty, and drug abuse, to name a few. However, years and years of research have brought a new perspective to the world of criminology- biological (that is specifically neurological, hormonal, and genetic factors) factors along with social factors can play an important role in the making of a criminal mind (Cooper et al. 2010).

Figure 1. The figure shows results from the study conducted by Ashly Sajous-Turner on 800 incarcerated men. The colored regions of the brain show diminished gray matter in the brains of incarcerated men who committed homicide as compared to those who committed less/non-violent crimes.

Advances in research have indicated that evidence for such behavior in criminals can be seen at the neurological level. Brain scans of more than 800 incarcerated men have shown that individuals who had committed a homicide actually had less gray matter than those who didn’t, and this finding can be significantly linked to the way these individuals process empathy, ethics, and morality (Sajous-Turner et al. 2019). Evidence reveals that criminals tend to have increased callosal connectivity and as mentioned in the statement that “these white matter atypicalities are evident well before adulthood” (Pape et al. 2015). A reduced volume of amygdala, an important part of the brain involved in emotional processes and most notably fear, has also been linked to many anti-social behaviors (Pardini et al. 2014). In fact, the prefrontal cortex which is associated with decision making, attention, emotional regulation, impulse control, and moral reasoning, can also be linked to criminal activity if there are “structural aberrations and functional impairments” in this region (Brower et al. 2001; Yang et al. 2009). 

Hormones have also been associated with felonious conduct. Cortisol is a hormone secreted by the adrenal cortex and acts as the primary stress hormone in the body which increases the production of sugars in the bloodstream and curbs functions that would be detrimental or non-essential in a fight or flight situation. Low levels of cortisol have been consistently associated with criminal activity (Ellis et. al 2009). 

Figure 2. This figure shows data from the Federal Bureau of Investigation. It indicates that males are more likely to be incarcerated than females in cases involving violent crimes as well those involving property (non-violent) crimes.

An interesting correlation has also been drawn between nefarious behaviour and androgens, or male hormones, particularly testosterone. This begs the question, do men have a greater biological predisposition to commit crime? Testosterone is a hormone secreted by the testicles in males and ovaries in females along with adrenal glands (though in small quantities) and is essential in the development of secondary sex characteristics in males. Androgens, however, can also be seen as Mephistophelian hormones which are hormones that are strongly associated with augmented aggression and belligerence. Many incarcerated individuals have been known to show higher levels of testosterone leading to hostile actions (Ellis et. al 2009). Studies on male Syrian hamsters have shown that perinatal exposure to androgens can actually have a more detrimental effect on behaviors that lead to aggression than post-pubertal exposure can (Romeo et al. 2003). Such findings have led many biosocial criminologists to find connections between elevated androgen levels and criminal behaviors quite noteworthy.

Genetics have shown to be an interesting basis of the biosocial perspective as well. Behavioral and genetic research on twins and adoptees have shown discernible differences between effects of environment and effects of genetics (Glenn et al. 2014). In fact, “females exposed to childhood sex abuse have exhibited alterations in the methylation of the 5HTT promoter region, which in turn has been linked to subsequent antisocial personality disorder symptoms “(Beach et al. 2011). Even dopamine genes DRD2 and DRD4 have been linked to criminal behaviour (Beaver et al., 2007). 

Combining the study of criminal minds with biology is irrefutably fascinating and has led to many incredible findings that help us better understand human behavior and the inner workings of the marvel that is the human body. However, we must also try to understand the shortcomings of such research due to biological factors like neural plasticity and effects of environmental stressors that can notably affect an individual’s behavior. There are also additional pitfalls due to the biases of an inherently unequal society that has been convicting the oppressed for a very long period of time which has affected research demographics in criminology rather significantly. 

Edited by Lauren Flamenbaum


Archer, J., Graham-Kevan, N., & Davies, M. (2005). Testosterone and aggression: A reanalysis of Book, Starzyk, and Quinsey’s (2001) study. Aggression and Violent Behavior10(2), 241–261.

Beach, S. R. H., Brody, G. H., Todorov, A. A., Gunter, T. D., & Philibert, R. A. (2011). Methylation at 5HTTmediates the impact of child sex abuse on women’s antisocial behavior: An examination of the Iowa adoptee sample. Psychosomatic Medicine73, 83–87. doi: 10.1097/PSY.0b013e3181fdd074 

Beaver, K. M., Wright, J. P., DeLisi, M., Walsh, A., Vaughn, M. G., Boisvert, D., & Vaske, J. (2007). A gene x gene interaction between DRD2 and DRD4 is associated with conduct disorder and antisocial behavior in males. Behavioral and Brain Functions3, 30. doi: 10.1186/1744-9081-3-30 

Brower, M. C., & Price, B. H. (2001). Advances in neuropsychiatry: Neuropsychiatry of frontal lobe dysfunction in violent and criminal behaviour: A critical review. Journal of Neurology, Neurosurgery & Psychiatry71, 720–726. doi: 10.1136/jnnp.71.6.720 

Cooper, J. A., Walsh, A., & Ellis, L. (2010). Is Criminology Moving Toward a Paradigm Shift? Evidence from a Survey of the American Society of Criminology. Journal of Criminal Justice Education21(3), 332–347.

Ellis, L., Das, S., & Buker, H. (2008). Androgen-promoted physiological traits and criminality: A test of the evolutionary neuroandrogenic theory. Personality and Individual Differences44(3), 701–711.

Ellis, L., Farrington, D. P., & Hoskin, A. W. (2009). Handbook of Crime Correlates (1st ed.). Academic Press.

Glenn, A. L., & Raine, A. (2014). Neurocriminology: Implications for the punishment, prediction and prevention of criminal behaviour. Nature Reviews Neuroscience15, 54–63. doi: 10.1038/nrn3640 

Ling, S., Umbach, R., & Raine, A. (2019). Biological explanations of criminal behavior. Psychology, Crime & Law25(6), 626–640. 

Pape, L. E., Cohn, M. D., Caan, M. W. A., van Wingen, G., van den Brink, W., Veltman, D. J., & Popma, A. (2015). Psychopathic traits in adolescents are associated with higher structural connectivity. Psychiatry Research: Neuroimaging233(3), 474–480.

Pardini, D. A., Raine, A., Erickson, K., & Loeber, R. (2014). Lower amygdala volume in men is associated with childhood aggression, early psychopathic traits, and future violence. Biological Psychiatry75, 73–80. doi: 10.1016/j.biopsych.2013.04.003 

Romeo, R. D., Schulz, K. M., Nelson, A. L., Menard, T. A., & Sisk, C. L. (2003). Testosterone, puberty, and the pattern of male aggression in Syrian hamsters. Developmental Psychobiology43(2), 102–108.

Sajous-Turner, A., Anderson, N. E., Widdows, M., Nyalakanti, P., Harenski, K., Harenski, C., Koenigs, M., Decety, J., & Kiehl, K. A. (2019). Aberrant brain gray matter in murderers. Brain Imaging and Behavior14(5), 2050–2061.

Savopoulos, P., & Lindell, A. K. (2018). Born criminal? Differences in structural, functional and behavioural lateralization between criminals and noncriminals. Laterality: Asymmetries of Body, Brain and Cognition23(6), 738–760.

van Bokhoven, I., van Goozen, S. H. M., van Engeland, H., Schaal, B., Arseneault, L., Séguin, J. R., Assaad, J.-M., Nagin, D. S., Vitaro, F., & Tremblay, R. E. (2006). Salivary testosterone and aggression, delinquency, and social dominance in a population-based longitudinal study of adolescent males. Hormones and Behavior50(1), 118–125.

Yang, Y., Raine, A., Lencz, T., Bihrle, S., LaCasse, L., & Colletti, P. (2005). Volume reduction in prefrontal gray matter in unsuccessful criminal psychopaths. Biological Psychiatry57, 1103–1108. doi: 10.1016/j.biopsych.2005.01.021

Image References

Author Removed At Request Of Original Publisher. (2016, March 25). 8.3 Who Commits Crime? – Social Problems. Pressbooks.

Sajous-Turner, A., Anderson, N. E., Widdows, M., Nyalakanti, P., Harenski, K., Harenski, C., Koenigs, M., Decety, J., & Kiehl, K. A. (2019). Aberrant brain gray matter in murderers. Brain Imaging and Behavior14(5), 2050–2061.

Leave a Reply

Your email address will not be published.