It has been over a year since the COVID-19 pandemic started, and scientific findings are starting to come in on the effects of the disease on the human brain.

Severe cases of COVID-19 affect brain health, which is no surprise. Any serious illness, especially when it leads to spending time in the intensive care unit (ICU) of a hospital, can lead to cognitive and mental health difficulties. What is more surprising is that some of these brain health deficits may persist long after recovering from COVID-19, and may be present even in people who did not spend time in a hospital or had only mild physical symptoms.

These long-term effects of COVID-19 have been referred to as “long COVID.” Long haulers, as they call themselves, have experienced prolonged symptoms such as fatigue, headaches, loss of smell, and subjective disruptions to cognition such as memory loss and trouble concentrating—referred to as brain fog. In one recent study (Graham et al., 2021), 81% of patients diagnosed with COVID-19 reported prominent and persistent brain fog that affected their quality of life.

The COVID Brain Study is an ongoing research project using Creyos tasks to better quantify the nature and extent of cognitive deficits resulting from the pandemic. The study is using Creyos tasks to compare people who had COVID-19 to people with no diagnosis, going beyond nonspecific brain fog complaints to examine precise cognitive domains such as memory, reasoning, verbal ability, and concentration. The study will also answer questions about how the severity of symptoms relates to cognitive deficits, who is most at risk for deficits, and how long long COVID may last.

COVID Long Haulers are Haunted by Both Mental Health and Physical Issues—But Only One Type of Symptom Leads to Cognitive Decline

Want a preview of the results of the COVID Brain Study? Our chief scientific officer, Dr. Adrian Owen, recently appeared on the CIFAR Virtual Talks webinar series to informally share early findings. View the webinar here. In short, people who were diagnosed with COVID appear to be impaired in some cognitive domains, such as speed of processing and problem solving, and those who had more serious physical symptoms of the disease also have more severe cognitive impairment.

The researchers also looked at mental health. Unsurprisingly, COVID appeared to affect a cluster of mental health symptoms, such as depression, anxiety, and limitations on emotional well-being. Perhaps more surprising was the finding that cognitive deficits were not associated with the mental health symptoms of the disease. From a clinical viewpoint, these results suggest that survivors suffering from the mental health fallout of COVID may or may not be cognitively impaired. However, survivors who experienced severe physical symptoms may require extra cognitive health care.

There are still unknowns, such as the duration of cognitive effects, and what exactly causes them. Direct effects of the virus on the brain are a strong possibility, given the results above, but additional effects of the pandemic—even among those who were never actually infected—such as social isolation, financial instability, and homeschooling require further study in the context of cognition.

Regardless of the cause or duration, the effects of these symptoms may be far-reaching. Employers have been urged to prepare for effects of long COVID, such as reduced productivity and more sick time. Healthcare practitioners should prepare for continued demand for their services and be in a position to address cognitive symptoms. Those in the mental health space in particular should expect long COVID to have separate effects on both mental health and cognition. Creyos Health provides objective cognitive and mental health assessments to quantify potential deficits and track recovery over time. Now, more than ever, it is essential to measure brain function in order to get millions of people affected by the pandemic back to their full potential.