How stress can lead to social inequality

Home Technologist Online How stress can lead to social inequality

How does stress affect our self-confidence when we compete? A new study shows that stress could be not only a consequence but also a cause of social and economic inequality, as it affects our ability to compete and make financial decisions.

Photo of a man who appears very frustrated and stressed, clasping his forehead and thinking about work, deadlines, mortgages, training, social and family life etc.

Stress is a staple of our lives today, and we know intuitively that it can influence our confidence – which is essential to our ability to compete in society. When we don’t feel confident, we are less likely to make the kind of decisions that can give us a financial and social edge over others. By driving social competition, confidence is central in the organisation and function of human societies, and marks the way we interact with each other.

At the same time, little is known about what influences people’s confidence. Two major factors seem to be stress and a person’s general anxiety. Technically, this is referred to as ‘trait anxiety’ and describes how prone a person is to see the world as threatening and worrisome. But the question is: how does stress and trait anxiety affect a person’s confidence in a competitive context?

Stress and confidence

Scientists from two Swiss universities, École Polytechnique Fédérale de Lausanne (EPFL) and University of Lausanne, have now shown that stress can actually boost the competing confidence of people with low trait anxiety, but significantly reduce it in people with high trait anxiety.

As reported in the scientific journal Psychoneuroendocrinology, the researchers designed a behavioural experiment that began with more than two hundred people taking two online tests. One test assessed their IQ; the other measured their trait anxiety.

A week later, about half of the study’s participants underwent a standard psychological procedure (called the Trier Social Stress Test for Groups, or TSST-G) designed to cause acute social stress, such as going through a mock job interview and performing mental arithmetic tasks before an impassive audience. The other half of the participants formed the control group, and did not undergo the stress-inducing procedure.

All participants – stressed and non-stressed – were then given two options in a game where they could win money. They could either take their chances in a lottery, or they could use their IQ score to compete with that of another, unknown participant’s; the one with the higher IQ score would be the winner.

In the non-stressed control group, nearly 60 per cent of participants chose the IQ score competition over the lottery, showing overall high confidence – regardless of their trait anxiety scores. But in the group that experienced stress before the money game, things were different.

The competitive confidence of stressed participants varied depending on their trait anxiety scores. In people with very low anxiety, stress actually increased their competitive confidence compared to their unstressed counterparts; in highly anxious individuals, it dropped.

The findings suggest that stress is a catalytic force acting on a person’s competitive confidence. Stress, it seems, can raise or suppress an individual’s confidence depending on their predisposition to anxiety.

Stress and cortisol

The researchers also found that the effects of stress on the participants’ confidence were mediated by the hormone cortisol. Cortisol is normally released from the adrenal glands, which sit on the top of our kidneys, in response to stress. Examining saliva samples from the stressed participants for the presence of cortisol, the scientists were able to connect the behavioural effects of stress to a biological mechanism.

In people with low anxiety, those with a higher cortisol response to stress also showed higher confidence. But in highly anxious people, high cortisol levels were associated with lower confidence.

The findings of this behavioural experiment can be seen as a simulation of confidence in social competition and the way it relates to socioeconomic inequality. Studies have shown that, in areas with wide socioeconomic inequality, people on the low end of the social ladder often experience high levels of stress as a consequence.

“People often interpret self-confidence as competence,” says EPFL neuroscientist Carmen Sandi, who spearheaded the study. “So if the stress of, say, a job interview, makes a person over-confident, they will be more likely to be hired – even though they might not be more competent than other candidates. This would be the case for people with low anxiety.”

Far from being only a product of competitive inequality, stress must now also be regarded as a direct cause of it. In other words, stress can become a major obstacle in overcoming socioeconomic inequality by trapping highly anxious individuals in a self-perpetuating loop of low competitive confidence.

Sandi is now interested in relating the effect of stress on confidence with brain imaging. Although there is much yet to be learned in this area, she believes it can change the way we look at social dynamics as a whole. “Stress is an important engine of social evolution,” she says. “It affects the individual and, by extension, society as whole.”

Adapted from article by Nik Papageorgiou, EPFL Mediacom



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