Summary by Dr. Beth Visser
Research Highlights
This paper describes a review of studies on the relationship between psychopathic traits, pain tolerance, and empathy for the pain of others.
Several studies suggest the possibility that a higher level of pain tolerance and reduced empathy for the pain of others may contribute to the antisocial behavior committed by people with psychopathic traits.
These findings are reliable for some measures of psychopathic traits and some kinds of pain,
Who participated in the study, and what did they do?
This review examined research papers published between 2000 and 2022, of which eight met the eligibility requirements for being included in the review (all studies had to include a psychopathy measure as well as a response to experiencing pain or to seeing others in pain). The eight eligible research studies included a total of 573 adult participants who were university students or community members.
Participants were either exposed to pain themselves (pain tolerance studies) or they viewed images of others in pain (pain empathy studies). In the pain tolerance studies, participants were subjected to physical pain stimuli including pressure (using specialized devices to cause pressure to the fingers or arms), electric shocks, or cold water (submerging a hand) in order to determine their pain tolerance. In the empathy studies, participants viewed images of other people’s hands and feet in painful situations or observed a partner receiving painful stimulation.
Measures in the eight studies included self-report surveys, EEG (using electrodes on the scalp to measure electrical brain activity), and fMRI (a brain scan that measures brain activity by tracking blood flow).
What were the findings?
The review found that individuals with higher psychopathic traits – specifically boldness (social dominance) and meanness (callousness) – showed a higher tolerance for physical pain. However, this finding was only true for pressure and electric shocks; psychopathic traits were unrelated to tolerance for cold temperatures. However, there was a great deal of inconsistency in the findings across the eight studies reviewed.
When participants viewed others in pain, in some studies, individuals with higher levels of psychopathic traits showed reduced brain activity in relevant areas. That is, their brains did not respond to the distress of others as strongly as the brains of those with lower psychopathic traits. Interestingly, in at least one other study, when viewing others in pain, individuals with more psychopathic traits demonstrated a pattern of activity suggestive of greater engagement in the processing of others’ pain.
What are the strengths and limitations?
A strength of this review was that the studies all incorporated standardized laboratory measures (like EEG and fMRI) as well as validated scales to measure psychopathic traits.
There were also a few limitations to this review. First, most participants were white undergraduate students, and some studies only included men, meaning the results might not generalize to everyone. Future research should include offender samples. A related concern was the relatively small sample sizes. Some of the studies included in this review had a small number of participants, which can make the results less reliable. Further, more research needs to be conducted to isolate the nature of the findings. Different brain scanning methods (EEG vs. fMRI) sometimes yielded different results, and the results differed by type of pain used (cold vs. pressure). The studies also incorporated varied psychopathy measures. Finally, the authors also suggested that future studies should control for the researcher’s presence or absence, as some participants may exaggerate their pain tolerance in the presence of another person.
What are the implications of this study?
This research suggests that a higher tolerance for pain might help explain the antisocial and violent behavior associated with psychopathy. If people with psychopathic traits are less bothered by their own pain, and their brains are less responsive to the pain of others, they may not fully appreciate the harmful impact of their actions.
The findings also indicate that empathy deficits in psychopathy may be rooted in neurology. Understanding these biological characteristics associated with psychopathy could inform interventions or help psychopathic individuals to better navigate social interactions.
Study Reviewed:
Alshukri, S., Blinkhorn, V., Warsaw, R. E., & Lyons, M. (2025). A systematic review investigating a tolerance for pain and empathy for other people’s pain in psychopathic traits within the general population. Personality and Individual Differences, 233, 112912. doi:https://doi.org/10.1016/j.paid.2024.112912
