Brain Mechanisms Involved in Post COVID Syndrome: A Narrative Review

Potentially, patients with COVID-19 can experience long-term disturbances after the acute infection period, even people with no symptoms or mild illness. Our current understanding of brain-associated post COVID-19 condition and why some people are more affected is limited. Post COVID syndrome or long COVID, with continuing symptoms of impaired brain functioning, in particular, 'brain fog', chronic fatigue, cognitive decline, mood disturbances, anxiety, and depression, is due to multiple molecular mechanisms. This narrative review updates most important cellular and molecular brain mechanisms as well as system mechanisms underlying post COVID syndrome.