# Evil’s Anatomy: Structural Correlates of Violent Behavior

## TL;DR

This paper reviews how brain structure differences may be linked to violent and psychopathic behaviors, suggesting a neurobiological basis for such traits.

## Contribution

The paper provides a narrative review connecting neuroanatomical alterations to violent behavior, emphasizing non-deterministic factors.

## Key findings

- Alterations in grey matter in brain regions like the prefrontal cortex and amygdala are linked to impulsivity and lack of empathy.
- Abnormalities in white matter and corpus callosum affect emotional regulation and decision-making.
- Homicide offenders show distinct neuroanatomical differences compared to other violent offenders.

## Abstract

Evil has been approached from various disciplines, but its relationship with neuroanatomy remains an expanding field of study. This narrative review examines neuroscientific evidence on the brain structure of individuals who display evil traits, such as psychopathy and antisocial behavior. It analyzes how alterations in grey matter and neural connectivity may influence the manifestation of violent behavior. A literature search was conducted in PubMed, Web of Science, and Google Scholar, using ResearchRabbit to identify related articles. The keywords "anatomy of evil," "serial killers," "psychopathy," "brain structure and violent behavior," and "neurobiology of crime" were used. Studies on neuroimaging, neuroanatomy, and psychopathy published in peer-reviewed scientific journals were included. The findings indicate that alterations in grey matter volume in key structures, such as the prefrontal cortex (orbitofrontal, ventromedial, and dorsolateral), temporal lobe (amygdala and hippocampus), cingulate cortex, and insula, are associated with impulsivity, a lack of empathy, and aggressiveness. Likewise, abnormalities in white matter and corpus callosum volume and connectivity may contribute to deficits in emotional regulation and decision-making. Furthermore, individuals with a history of homicide exhibit significant neuroanatomical differences compared with other types of violent offenders. Although evidence suggests that the predisposition to evil may have a neurobiological basis, these factors are not deterministic. Environmental influences, such as childhood abuse and social deprivation, can modulate the impact of these brain alterations. Longitudinal studies and functional MRI are essential for distinguishing the causes from the consequences of the observed anatomical differences. In conclusion, there are neuroanatomical patterns that could be linked to violent and psychopathic behaviors, but their study still requires greater depth to establish causal relationships. Understanding the neurobiology of evil can provide valuable insights for criminology, forensic psychiatry, and the development of effective early intervention strategies.