A new study, published in the journal JAMA Network Open, suggests that brain fog can persist for months in COVID-19 patients, even in those who were not hospitalized. 

Researchers noted that around one-fourth of COVID-19 patients in a Mount Sinai Health System registry reported some issues with their memory. While hospitalized patients had a higher likelihood of having brain fog following SARS-CoV-2 infection, some outpatients also reported having cognitive impairment.

There was a relatively high frequency of cognitive impairment several months after getting infected with COVID-19, noted researchers. Impairments in executive functioning, category fluency, memory encoding, processing speed, and recall dominated in hospitalized patients… (CNN, October 22, 2021)