Recent research suggests that people with higher levels of certain socially aversive personality traits, particularly narcissism and psychopathy, tend to have lower physical and psychological responses to acute stress. These findings provide evidence that these personality traits may provide a type of biological resilience in the face of high-pressure situations. This study International Journal of Psychophysiology.
Psychologists use the term dark triad to describe a group of three overlapping personality traits that involve ruthlessness and a tendency to manipulate others. These three traits are narcissism, psychopathy, and Machiavellianism. Narcissism involves inflated self-esteem, grandiosity, and a strong desire for control.
Psychopathy is characterized by a lack of empathy, impulsive behavior, and a tendency to ignore rules. Machiavellianism involves a strategic and calculating approach to social interactions. Machiavellian people often manipulate others for personal gain without remorse.
Adam O’Riordan, director of the Institute for Psychophysiology, Health, and Stress Assessment and assistant professor of psychology at the University of Texas at San Antonio, wanted to understand how these properties interact with the body under pressure.
“My research focuses on how psychological factors influence stress coping and cardiovascular health,” O’Riordan told SciPost. “The dark triad is important in this study, as recent evidence suggests that traits such as psychopathy and narcissism can confer resilience under certain circumstances, despite their well-established maladaptive effects on interpersonal relationships. Of particular interest. We therefore aimed to investigate whether Dark Triad traits (narcissism, psychopathy, and Machiavellianism) are associated with cardiovascular and psychological responses when exposed to stress.”
To understand how the body responds to direct pressure, scientists look at cardiovascular reactivity. This concept refers to the physical changes in the heart and blood vessels that occur during stressful events. For example, a person’s heart rate may increase or blood vessels may constrict, increasing blood pressure. High cardiovascular reactivity means your heart works harder when you feel anxious or threatened.
Over time, an exaggerated physical response to stress tends to increase your risk of developing heart disease and other health problems. A major problem with past research on personality and stress is that the three Dark Triad traits share a lot of psychological overlap. People who score high on one trait often score high on other traits as well. This is because all three share a common core of adversarial relationships.
With this overlap in mind, the researchers designed this project to examine all three traits simultaneously. By modeling traits together, scientists can isolate the independent and unique effects of each aspect of a given personality. Researchers recruited 139 undergraduate students for a controlled laboratory experiment. There were slightly more women than men in the sample, and the average age of participants was approximately 19 years.
Before starting the test, researchers screened participants who had pre-existing cardiovascular disease or were taking medications that affect heart rate. Participants first completed a series of questionnaires to measure baseline levels of narcissism, psychopathy, and Machiavellianism. They then sat quietly for 10 minutes so the research team could record baseline physical indicators. During this resting phase, the scientists measured systolic blood pressure, diastolic blood pressure, mean arterial pressure, and heart rate at regular intervals.
After a rest period, participants completed a highly demanding mental arithmetic task designed to induce acute psychological stress. They were asked to start with the number 1022 and continue subtracting the number 13. They had to do the calculations in their heads and say their answers out loud to the research team.
If participants made a calculation error or took more than 10 seconds to respond, the researchers forced them to start over. To make the situation even more uncomfortable, the researchers wore white lab coats. This detail was intended to create formal social evaluation and a sense of psychological distance between participants and observers.
Blood pressure and heart rate monitors continuously measured participants’ physical responses throughout the five-minute math challenge. The researchers calculated cardiovascular reactivity by subtracting participants’ resting baseline measurements from their stressful math task measurements. The researchers also considered factors such as age, gender, smoking habits, and weight to ensure that these external variables did not skew the results. Immediately before and after the task, participants rated how stressed and anxious they felt on a numerical scale.
The mental arithmetic task was successful in inducing a significant increase in physical and psychological stress across the group. Heart rates increased, blood pressure spiked, and participants reported feeling much more anxious than before they began the task. However, how strongly participants respond depends on their specific personality traits.
Participants who scored high on narcissism reported significantly reduced feelings of anxiety after the task compared to other participants. Higher levels of narcissism predicted lower increases in systolic blood pressure, the pressure in the arteries when the heart beats. Additionally, people high in narcissism had a lower rise in mean arterial pressure, which measures the average pressure in blood vessels during one heartbeat.
Psychopathy also influenced participants’ reactions to unpleasant math tasks. Those with higher psychopathy scores reported that their tasks were significantly less stressful overall. These people also showed a much smaller increase in heart rate during difficult math problems.
In initial tests, Machiavellianism did not show a strong association with physical stress responses. To ensure their findings were accurate, the researchers ran an additional statistical model that included all three Dark Triad traits simultaneously. This statistical step helps separate the unique effects of each trait from common operational characteristics.
The association between narcissism and lower mean arterial pressure remained significant when all three traits were observed simultaneously. The association between psychopathy and heart rate-lowering responses also remains strong. The association between narcissism and lower subjective anxiety remained consistent in these more rigorous models.
Some of the initial findings lost statistical significance during these more rigorous tests. The relationship between narcissism and lower systolic blood pressure is too weak to be considered a robust effect. The association between psychopathy and lower self-reported stress also faded in the adjusted model. Interestingly, when all traits were combined, Machiavellianism actually predicted slightly higher levels of subjective anxiety.
Mr O’Riordan summarized the main takeaways from the experiment. He noted that the findings provide a new perspective on typically negative personality types. “Our findings revealed that people high in narcissism and psychopathy have lower anxiety levels, are less likely to experience stress, and exhibit lower blood pressure and heart rate responses when exposed to psychological stress,” O’Riordan said.
“So while these traits have a ‘dark’ side and are often seen as maladaptive due to their hostile core, there also appears to be something about these traits that may help individuals cope with stress more effectively,” O’Riordan said. “Whether this is caused by a sense of superiority, a belief that one is better than others, or a more callous and emotionally numb mood remains an open question for future research to address.”
Although these findings are informative, the authors note that the current study has several limitations. The questionnaires used to measure Dark Triad traits were relatively short and did not capture all the subtle aspects of personality. For example, the study primarily measured grandiose narcissism, but overlooked vulnerable narcissism, which is associated with anxiety and defensiveness.
The statistical reliability of personality surveys in this sample was also somewhat modest. This means that the questions may not have measured the trait as completely as a longer, more detailed survey. Another limitation involves the specific group of people who participated in the experiment.
The sample consisted of completely healthy young college students. Physiological effects may look different in older adults and people with pre-existing health conditions. Additionally, laboratory work represented only certain types of acute stress. Real-world stressors that involve more intense social judgment or personal threats can trigger a variety of physical reactions.
Some scientists suspect that a decreased physical response to stress may actually be a sign of emotional blunting. Emotional blunting occurs when the brain is unable to properly process important emotional information, which can lead to maladaptive behavior. However, because the highly narcissistic and psychopathic participants did indeed report reduced anxiety, the authors suspect that their reduced physical responses may reflect a protective form of biological resilience.
This resilience may help explain why some socially aversive traits are associated with improved long-term cardiovascular health in certain circumstances. The ability to keep heart rate and blood pressure stable under pressure is a physical advantage. This suggests that traits such as narcissism and psychopathy, despite their negative social consequences, serve as internal buffers against the physical wear and tear of daily stress.
The study, “Examining the Association between Dark Triad Personality Traits and Cardiovascular Reactivity to Acute Psychological Stress,” was authored by Adam O’Riordan, Tyler L. Minnie, and Aisling M. Costello.

