The concern raised by the COVID-19 pandemic would have a negative impact on the judgment of certain individuals, shows a Montreal study.
This is a worrying finding at a time when many are called upon to make choices concerning their health or that of those close to them – such as the decision to be vaccinated or not.
Scientists from McGill University and the Montreal Neurological Hospital Institute (The Neuro) interviewed more than 1,500 people online between April and June 2020.
In particular, they were asked to quantify their level of concern about the COVID-19 pandemic. They were also asked to complete a battery of psychological tests to assess their basic cognitive abilities, such as processing and maintaining information in memory.
For example, participants were asked to associate pairs of numbers and symbols according to a fixed rule. They were also offered hypothetical choices between a “certain” option (a guaranteed gain of $ 75) and a “risky” option (25% chance of winning $ 0 and 75% chance of winning $ 100) to measure their success. attitude to risk.
The researchers observed a decrease in the speed of information processing and the ability to retain the information necessary for the performance of tasks among the participants who indicated to be the most worried by the pandemic. Even for the simplest cognitive tasks, the results obtained by the group during the pandemic were lower than the results obtained before the pandemic.
“The past two years have been really stressful, so it’s no surprise that there are effects on our cognitive abilities,” said Kevin da Silva Castanheira, a graduate of the McGill University Psychology Department and the lead author of the study.
If scientific studies had previously testified to a harmful impact of stress or worry on cognitive abilities, this one is the first to do it not in the laboratory, but “in real life”, he said. he adds.
Risk assessment
The level of worry also increased the likelihood of participants taking risks, and the researchers observed a direct correlation between the two: the more the participant reported being stressed by the pandemic and all that came with it, the better their judgment seemed. suffer from it.
The study found that worry about the pandemic caused participants to underestimate the probable eventualities and overestimate the improbable eventualities. The concern caused by COVID-19 therefore seems to have had an impact on the decision-making capacities of some.
This could, for example, influence attitudes towards vaccination, mask wearing or social distancing, said Mr. da Silva Castanheira.
“The participants’ perception of risk was distorted,” he explained. Those most worried were more likely to leave out the most likely outcomes and focus on the more unlikely outcomes. ”
This could then distort the perceived risk of experiencing negative effects from the vaccination, da Silva Castanheira said.
The findings of this study were published by the scientific journal PLOS One.