Mechanisms Behind COVID ‘Brain Fog’ Beginning to Come to Light
July 11, 2022
New research published in Cell analyzed the brains of mice previously infected with mild respiratory COVID-19 and found residual signs of inflammation in several brain cell populations. These damages are thought to potentially explain the mechanisms behind the cognitive disruptions seen in some post-COVID-19 infections. The cognitive disruptions have become known as “COVID fog” or “brain fog” and is characterized by “impaired attention, concentration, speed of information processing, memory, and executive function” (Becker et al., 2021; Nasserie et al., 2021).
Interestingly, there appears to be a resemblance between the syndrome of cancer-therapy-related cognitive impairment (CRCI), also referred to as “chemo fog” and the brain fog seen in those with long COVID. This similarity has led some researchers to look into whether the two share pathophysiological mechanisms. The neurological symptoms in CRCI have been linked to “a distinct subpopulation of microglia that reside in white matter [that] are selectively activated by systemic insults such as exposure to the chemotherapy drug methotrexate.” The subsequent damage leads to an impairment of cellular homeostasis (maintaining a balance of several factors that make a cell healthy) and plasticity (the ability of the nervous system to change its activity in response to intrinsic or extrinsic stimuli by reorganizing its structure, functions, or connections) processes.