Many Scientists have questioned the results of the new study by a team of British researchers from the Imperial School of London, who found that people infected with COVID-19 suffer a significant deterioration in their cognitive abilities. What’s wrong with this investigation?

In their work, researchers tried to assess how well the brains of people affected by coronavirus perform tasks such as remembering words or joining dots of a puzzle. The tests used by them are similar to the tests used to assess the brain’s ability in diseases such as Alzheimer’s.

Researchers concluded that cognitive deficits were substantial among people who had been hospitalized with COVID-19. In the worst cases, “equivalent to the average 10-year decline in global brain performance between the ages of 20 and 70” were discovered.

While this and other findings have yet to be examined by experts who have not been directly involved in this research, some scientists have already questioned the results of the Great British Intelligence Test.

“The cognitive function of the participants was not known before the study and the results also do not reflect long-term recovery, so any effect on cognition can be short-term,” said Joanna Wardlaw, professor of applied neuro-imaging at the University of Edinburgh.

Derek Hill, a professor at College London, agrees that the study’s findings cannot be entirely reliable, as scores had not been compared before and after infection. In addition, the investigation involved a large number of people who self-reported having suffered COVID-19, i.e. they had no evidence to confirm that they had actually suffered from COVID-19.

“Overall (this is) an intriguing but inconclusive piece of research into the effect of COVID on the brain,” Hill noted.

As researchers try to better understand the long-term impact of COVID-19, it is important to investigate further the extent to which cognition is affected after infection, and whether some people suffer permanent damage to brain function.