People struggling with “long Covid,” or the persistence of symptoms after an initial Covid-19 infection, can face cognitive difficulties such as “brain fog” and memory problems.
To better understand long Covid’s effect on the brain, the new study put more than 3,000 participants through 12 different types of cognitive tests designed to measure memory, processing speed, attention, motor control and other thinking skills. A little over half of the participants had previously tested positive for Covid-19, and all were recruited through the Covid Symptom Study Biobank smartphone app.
In the first round of testing in 2021, researchers found the cognitive impairment associated with long Covid was clear, comparable to the brain being under “mild or moderate symptoms of psychological distress,” or ten years of aging, write the authors in the paper. During the second round of testing, which took place in 2022, patients showed no significant improvement. At that point, some participants’ cognitive decline had lasted nearly two years after infection.
The positive takeaway? Once a person’s Covid symptoms disappeared—regardless of whether they had persisted for three months or one week—their cognitive function appeared to recover.
