Dr. Andrew Levine

If the symptoms are due, even partially, to a psychiatric condition such as PTSD, treatment will help manage those symptoms, and provide a clearer view of any underlying brain issues.

"Once they have treatment, and hopefully have some remission of their psychiatric symptoms, if the cognitive complaints and the deficits on neuropsychological tests are still there, then that’s more evidence that something else is going on," Kaseda said. "It's going to be important for clinicians across the board to be keeping up with the literature that's coming out, to make sure they have the most up to date information as these survivors are starting to present for neuropsychological testing."

Kaseda began pursuing this question based on her experience working with patients with mild traumatic brain injury, such as concussion. "When these symptoms persist for months or years after the original injury, it's much more likely to be due to the presence of a psychiatric disorder," she said.

A review of data from the SARS and MERS outbreaks showed that those survivors had heightened risk for PTSD.

In the case of COVID-19, the symptoms of PTSD may arise in response to the invasive measures needed to treat the patients, including intubation and ventilation, which can be traumatic for fearful patients. Other times, delirium causes patients with COVID-19 to suffer hallucinations, and the memory of these terrifying sensations continues to plague the recovered patient.

In addition to patients who have been hospitalized, frontline health-care providers can be similarly affected due to the constant stress and fear they face at work. And for some people, the anxiety of living through a pandemic, being isolated from friends, and battling the constant fear of an invisible threat can deliver a similar blow to thinking and memory skills.

While a PTSD diagnosis might not sound like good news, there are many available treatments for the disorder, including psychotherapy and medications. By comparison, researchers are still working to understand the direct neurological effects of COVID-19. "Treatment options (for COVID) are still quite a way's out, because it's still an evolving situation," Kaseda said.

"We don't actually know anything yet from survivors of COVID-19," Kaseda said. "Until we have that data, it's very hard to say what actual percentage of patients are going to have cognitive complaints because of direct effects of the virus, because of medical intervention, or because of psychiatric concerns."