Psychopathic individuals are known to commit a disproportionate amount of violence and crime.
Yet the connections between psychopathy, intelligence and aggression are complex.
A new study unpacks the links between these dangerous traits in men and women.
Key Facts:
- Psychopathy was assessed using the Psychopathy Checklist: Screening Version which divides psychopathy into 4 facets – interpersonal, affective, lifestyle and antisocial.
- Intelligence was measured using the Raven’s Progressive Matrices test of fluid intelligence.
- Aggression was measured using the Aggression Questionnaire, looking at total aggression as well as physical, verbal and indirect aggression.
- The antisocial facet of psychopathy was linked to lower intelligence in both men and women.
- Intelligence moderated the psychopathy-aggression link differently for men and women across aggression types.
Source: J Interpers Violence
Psychopathy is a personality construct characterized by callous, manipulative behaviors and a lack of empathy.
While it has long been associated with violence, crime and aggression, the connections between psychopathy, intelligence and different forms of aggression are not fully understood.
Psychopathy, Intelligence and Aggression Links (Study)
Researchers assessed psychopathy using the Psychopathy Checklist: Screening Version (PCL:SV), which measures psychopathy based on 4 underlying facets:
- Interpersonal – features like superficial charm, grandiosity and deception
- Affective – lack of empathy, remorse or guilt
- Lifestyle – impulsivity, irresponsibility, lack of goals
- Antisocial – poor behavior controls, aggression, criminal versatility
Fluid intelligence was measured using the Raven’s Progressive Matrices (RPM), a commonly used non-verbal IQ test.
Aggression levels were measured across several subtypes using the Aggression Questionnaire: total aggression, as well physical, verbal and indirect aggression.
The study analyzed data from 556 adults in Bulgaria, 70% men and 30% women, with an average age of 28 years.
Over half met criteria for substance dependence and 7% met the threshold for psychopathy based on their PCL:SV scores.
Antisocial Traits Linked to Lower Intelligence in Men and Women
When examining links between psychopathy facets and intelligence, the researchers found the antisocial facet was significantly associated with lower fluid intelligence in both men and women.
The antisocial facet captures extensive antisocial behaviors like poor impulse control, aggression, delinquency, and criminal versatility.
The findings suggest that individuals who score higher on this facet tend to have deficits in fluid intelligence, which involves reasoning, problem solving, and adapting to novel situations.
This aligns with prior research linking the antisocial facets of psychopathy to lower IQ.
It also fits with evidence that the brain regions implicated in psychopathy, like the prefrontal cortex, overlap with those involved in fluid intelligence.
No other psychopathy facets were independently linked to intelligence in men or women when accounting for the overlap between the different facets.
This highlights that the antisocial facet seems to be driving the association between overall psychopathy and lower intelligence.
Intelligence Moderates Psychopathy-Aggression Link Differently in Men and Women
More interestingly, the researchers found that fluid intelligence moderated the relationship between psychopathy facets and aggression in a sex-specific manner.
For men, lower intelligence strengthened the link between antisocial psychopathy traits and overall aggression levels.
Men with high antisocial scores and lower IQ were the most aggressive.
In women, intelligence did not impact the relationship between psychopathy facets and total aggression.
When looking at subtypes of aggression, further sex differences emerged:
- For physical aggression, psychopathy facets were linked to aggression in women only. The interpersonal, affective and antisocial facets were all associated with higher aggression. In men, only the antisocial facet was linked to physical aggression.
- For indirect aggression, intelligence strengthened the psychopathy-aggression link differently for men and women. Higher intelligence coupled with antisocial traits predicted greater indirect aggression in women. In men, higher intelligence alongside affective psychopathy traits predicted higher indirect aggression.
- For verbal aggression, the antisocial facet was linked to aggression in men only. Intelligence was not a moderator for either sex.
Taken together, the results indicate intelligence may amplify the risk of aggression associated with psychopathic traits in specific ways that diverge for men and women.
While low intelligence exacerbates the aggression risk linked to antisocial traits in men, higher intelligence may compound the danger of indirect aggression tied to affective traits in women versus men.
This highlights the complexity of how dangerous personality traits, cognitive abilities and sex interact to potentiate different forms of aggression.
Key Implications & Future Directions
By helping unpack the links between psychopathy facets, intelligence and aggression subtypes in men versus women, this study has some notable implications:
- It further highlights the multidimensional nature of psychopathy and need to examine facets individually.
- The antisocial facet stands out in its consistent ties to lower intelligence and aggression across sexes. Targeting antisocial behaviors may be important for violence prevention in both men and women.
- Women show more nuanced associations between psychopathy facets and aggression types, illustrating the need for sex-specific risk assessment and treatment approaches.
- Higher intelligence may compound aggression risk linked to certain psychopathy facets, challenging views of these associations as solely deficit-driven.
- Findings underscore relationships between dangerous personality traits, cognitive abilities and aggression are complex, multi-faceted and differ for men and women.
More research is needed to replicate the findings and better understand the neurocognitive mechanisms underlying the moderating role of intelligence.
Studies across diverse settings and samples will help clarify generalizability of the sex differences.
Ultimately, further unpacking the intersections between psychopathy, intelligence and aggression can inform improved prevention, risk assessment and treatment strategies to reduce violence in high-risk populations.
Differential approaches tailored to men versus women may be needed to target sex-specific pathways to aggression.
References
- Study: Fluid intelligence moderates the link between psychopathy and aggression differently for men and women
- Authors: Nicholas D. Thomson et al. (2020)
