A new analysis from Imperial's human challenge study of COVID-19 has revealed subtle differences in the memory and cognition scores of healthy volunteers infected with SARS-CoV-2, which lasted up to a year after infection. The researchers say all scores fell within expected normal ranges for healthy individuals and no one reported experiencing any lasting cognitive symptoms such as brain fog. The findings, published in the journal eClinicalMedicine , show a small but measurable difference following highly intensive cognitive testing of 18 healthy young people with infection compared to those who did not become infected, monitored under controlled clinical conditions.

The team explains that incorporating such sensitive cognitive testing into future studies could help reveal more detailed insights into how infections may alter brain function and could help to find ways to reduce these processes when they cause symptoms. Senior author Professor Adam Hampshire, from the Department of Brain Sciences at Imperial College London and now based at King's College London, explained, "We know that COVID-19 can have lasting impacts on our memory and ability to carry out common cognitive tasks. However, much of the scientific evidence we have comes from large studies based on self-testing and reporting, or where there's a range of variables that could increase or reduce these effects.

"Our work shows that these cognitive effects are replicated even under carefully controlled conditions in h.