COVID’s Impact on the Brain: What’s Hot in 2022

Recent findings of acute and chronic brain conditions from COVID-19 are shedding light on this apparently multifactorial condition

“Covid and the Brain: A topic that is of major interest today but one that didn’t exist at the time of the last Society for Neuroscience Meeting in 2019 .”

– Barry Everitt, President of the Society for Neuroscience, Opening Speech at Neuroscience 2021

While there continue to be advances in neuroscience research in many new areas with significant growth going in to 2022, including yet not limited to cellular regenerative medicine, gene therapies to treat neurological disorders, and approval of the classical psychedelics to treat mental health disorders, COVID’s impact on the brain has emerged as one of the hottest topics.

As more cases of COVID occurred, primarily from China and Italy and other places very early infected by the pandemic, neurologic presentations in hospitalized patients also began to arise. Dr. Igor Koralnik from Northwestern University and Dr. Serene Spudich from Yale University discussed these recent findings of acute and chronic brain conditions from COVID-19 infection at this year’s Neuroscience 2021 Meeting.

Some of the neurological complications of acute COVID-19 were immune-mediated neuropathogenesis. More than 91% of the neurologic manifestations were myalgia, headache, encephalopathy, dizziness, dysgeusia and anosmia. Ischemic and hemorrhagic strokes, movement disorders, ataxia, peripheral nervous system disorders and seizures made up 0.2 to 1.4% of those with generalized fatigue in 79.4% of patients. Markers of inflammation (neuronal injury) were shown as elevated in cerebral spinal fluid and the patterns of this inflammation differed from what was found in blood (systemic inflammation) indicating that there was localized, directly autoimmune complications because of COVID-19 viral infection. There was significant activation of microglia and CD8+ T cell infiltration in the brains of humans (post-mortem) with COVID-19 indicating simultaneous neuroinflammation which later triggered the onset of various autoimmune disorders.

The “long-haulers,” or those millions of people who were infected with COVID-19 and became survivors reported this feeling that they were getting or had dementia or brain fog as well as other reported neuropsychiatric issues. There isn’t a lot of systematic data with these lingering issues, but the timing has been identified from 1-7 months out from acute COVID-19. There are a lot of interesting studies ongoing (imaging, immune profiling and looking at antibodies in blood) of those who tested positive for COVID-19. These will start to unfold more solid conclusions about COVID and the mind. As more data and research follows, the consensus from the neuroscientific community is that COVID-19 is becoming a multi-factorial disease.

-- Carina Peritore, PhD, Sr. Product Manager, Neuroscience Discovery, Charles River

Our What's Hot series are annual forecasts provided by Charles River's thought leaders. Check out here what our scientists are predicting for 2022 and what they called out in years past.