Why ‘dark’ personality traits can help us cope with stress more calmly

A new study has shown that students with more pronounced narcissistic traits reported lower levels of anxiety during a stress test, whilst participants with more pronounced psychopathic traits exhibited a smaller increase in heart rate.

The study has been published in the International Journal of Psychophysiology.

Details

Psychologists refer to three groups of personality traits as the ‘dark triad’: narcissism, psychopathy and Machiavellianism. Narcissism is associated with an inflated sense of self-importance and a desire for dominance. Psychopathic traits are associated with emotional coldness, impulsivity and a reduced sensitivity to rules. Machiavellianism is associated with calculating behaviour and a tendency to use others for one’s own ends.

In everyday life, such traits can be detrimental to relationships: a person may be less empathetic, more manipulative or overly focused on their own benefit. But the researchers were interested in a different question: how do the bodies of people with such traits react to short-term stress?

The study involved 139 students from a major research university in the south-west of the US. The average age of the participants was around 19. Before the test, the researchers excluded people with cardiovascular disease and those taking medication that affects heart rhythm.

How the experiment was conducted

First, the participants completed questionnaires that measured the severity of ‘Dark Triad’ traits. They then sat quietly for about 10 minutes whilst the researchers measured their resting heart rate and blood pressure.

After that, the stress test began. Participants were given a mental arithmetic task: they had to subtract 13 from 1022 and continue counting aloud. If a participant made a mistake or answered too slowly, they were asked to start again. Throughout this, they were observed by a researcher in a white lab coat — this heightened the sense of being assessed and under pressure.

During the task, the participants’ heart rate and blood pressure were constantly monitored. Before and after the test, they were also asked to rate how much stress and anxiety they felt.

What they found

On average, the task did indeed cause stress: participants’ heart rates and blood pressure rose, and they reported feeling more anxious. However, the intensity of the reaction depended on personality traits.

People with more pronounced narcissistic traits reported feeling less anxious after the task. They also showed a smaller increase in mean arterial pressure — a measure that reflects the average pressure in the blood vessels during the cardiac cycle.

Participants with more pronounced psychopathic traits perceived the task as less stressful and showed a smaller increase in heart rate. Machiavellianism, unlike the other two traits, did not present the same ‘calm’ picture: in a more rigorous model, it was even associated with slightly higher subjective anxiety.

Why might this be the case?

One possible explanation is self-confidence. A person with pronounced narcissistic traits may perceive a stressful situation as less threatening because they have a stronger belief in their own superiority or control.

In the case of psychopathic traits, a different explanation is possible: emotional coldness and reduced sensitivity to threat. Such a person may react less strongly to pressure, judgement or an uncomfortable situation.

But these are still hypotheses. The study does not prove exactly which mechanism lies behind the weaker response to stress. The authors note that future research should investigate whether this represents genuine stress resilience or a blunted emotional response.

Why this is not a ‘superpower’

A reduced response to stress does not always mean something unequivocally positive. On the one hand, if heart rate and blood pressure fluctuate less under pressure, this may be beneficial for the body. High cardiovascular reactivity to stress is considered, in the long term, to be one of the risk factors for heart health.

On the other hand, a weak response may be linked not to resilience, but to emotional numbness. In other words, a person does not necessarily ‘cope better’ with stress — perhaps they simply process the threat less effectively or perceive its social significance as less significant.

The main conclusion is therefore a cautious one: certain personality traits may be linked to a calmer physiological response to a single laboratory stress test. But this does not make these traits beneficial in general.

Why it is important not to confuse traits and diagnoses

This study is not about clinical diagnoses. Participants were not labelled ‘narcissists’ or ‘psychopaths’ in the medical sense. They simply scored higher or lower on a personality traits questionnaire.

This is an important distinction. Many people may possess individual narcissistic, cold or manipulative traits, but this does not indicate a personality disorder and does not provide grounds for a diagnosis.

Nor does the study condone harmful behaviour. Manipulation, harshness or a lack of empathy can destroy relationships and harm those around you, even if the body reacts more calmly during a specific stressful task.

Limitations of the study

The study has several important limitations. Firstly, the sample size was small: 139 people. Secondly, the participants were young, healthy students, so the results cannot automatically be generalised to people of other ages, those with chronic illnesses, or those with different life experiences.

Thirdly, the stress was laboratory-based and very specific: mental arithmetic under observation. In real life, stress can be prolonged, personal, traumatic, or related to work, war, illness, loss or relationships. Reactions in such situations may be quite different.

Fourthly, short questionnaires were used to measure the ‘dark triad’. Whilst these are convenient for experiments, they do not capture all the nuances of personality. For example, narcissism can manifest not only as grandiosity and self-confidence, but also as vulnerability — accompanied by strong self-doubt and defensive behaviour.

Why this is important

The research helps us understand why people react differently to stress. Some become anxious quickly, with a sharp rise in their heart rate and blood pressure. Others remain outwardly and physiologically calmer — but the reasons for this calmness may vary.

This is important for psychology and medicine because stress is linked not only to emotions but also to the body. If personality traits influence cardiovascular responses, this could help us better understand individual health risks and different ways of coping with stress.

However, this is not yet practical advice, nor is it a guide to ‘developing dark traits’. Rather, it is a reminder: even unpleasant personality traits may have complex biological links that cannot be described simply as ‘good’ or ‘bad’.

Source

Study: Adam O’Riordan, Tyler L. Minnigh, Aisling M. Costello, “Examining the association between the dark triad personality traits and cardiovascular reactivity to acute psychological stress”, International Journal of Psychophysiology, 2026.