Self-promotion, but not antagonism, in narcissism linked to testosterone

Grandiose narcissists have an unreasonably high sense of their own importance, and deeply crave the admiration of others. Many lack the ability to understand others' feelings, feel more envy than is typical, and are prone to bragging. 

According to a popular model, this type of narcissism has two distinct facets; as a team led by Marcin Zajenkowski at the University of Warsaw note in their recent paper in Psychological Science, the 'agentic' facet is the tendency to self-promote, to win other people's esteem and social influence. If the person with grandiose narcissism's status is threatened, however, the 'antagonistic' facet kicks in, manifesting as arrogant, demeaning, argumentative, or exploitative behaviour.

Exactly what might cause grandiose narcissism is unclear. But in their study of 283 young men, Zajenkowski and his colleagues found that those with higher levels of the hormone testosterone in their blood scored higher on measures of agentic — though not antagonistic — narcissism. This work suggests that testosterone is associated with of the default 'agentic' aspect of narcissism, and that the two facets have distinct biological underpinnings. 

Scientists have been looking at the link between testosterone and narcissism for quite a while now, but previous research has produced mixed results. The team suspects one reason that some earlier studies failed to find a link between the two is because they considered only the total scores of narcissism questionnaires, rather than scores probing the individual facets. 

To address this, the team used a suite of questionnaires to gather three measures of agentic narcissism, two measures of antagonistic narcissism, and two measures of neurotic narcissism (which comprises the antagonistic facet and neurotic facets, including distrust and shame). They also took blood samples from the participants to measure testosterone levels. Finally, they explained to the participants that men vary in their general testosterone levels, and asked them to estimate where they'd sit on that spectrum, using a scale from 1 to 25. 

Once the data were analysed, it became clear that testosterone levels weren't linked to measures of antagonistic and neurotic narcissism. However, higher levels of testosterone were associated with higher scores on all three of the agentic narcissism measures. What's more, the researchers found that the participants had some (small) insight into their own testosterone levels. 

These results fit well with other earlier studies on those high in narcissistic traits and on testosterone. In men, testosterone is thought to drive the pursuit of prestige and glory, factors which characterise agentic, but not antagonistic, narcissism. Earlier work also shows that when men win — or are just led to believe that they have won — a competition, their blood testosterone levels also rise. This is thought to boost their confidence and willingness to risks, which then improves their chances of winning again.

This bi-directional positive feedback loop is known as the 'winner effect'. As the team notes, "Elevated levels of testosterone may predispose agentic narcissists to actively seek situations they perceive as opportunities to attain glory." And success in these endeavours (whether real or imagined) may then boost their testosterone levels further still, motivating them to seek out other ways to promote themselves. 

There are some limitations to the study. Because the role of testosterone in narcissism-related behaviours beyond cisgender men are less clear, the team studied only one sex. In addition, their participants were mostly young Polish undergraduate students, which may limit how well these findings replicate from other demographics. It's also important to note that grandiose narcissism is a complex condition; factors beyond testosterone likely also play roles in the development and maintenance of agentic behaviour.

Still, their results could indeed help to explain why there have been mixed findings from earlier research on testosterone and narcissism, and certainly suggest that higher testosterone levels play a role in some narcissistic behaviours. 

Read the paper in full: https://doi.org/10.1177/09567976231184886