Brain's Frontal Lobes Electrical Activity May be Impacted by COVID-19
Ever since the pandemic hit, scientists worldwide have been working tirelessly to understand various aspects of SARS-CoV-2, the virus that causes COVID-19. While the initial focus was primarily on the lungs, heart, and immune system, research is now shedding light on the potential neurological effects of the virus.
Recent studies suggest that neurological symptoms such as headaches, confusion, delirium, impaired consciousness, seizures, and strokes are quite common among patients with severe COVID-19. The researchers are investigating how these symptoms might be linked to the brain, and an electroencephalography (EEG) test could potentially hold the answer.
Let's dive into the details:
When doctors suspect a patient has neurological symptoms due to COVID-19, they might refer them for an EEG test. This involves placing electrodes on the scalp to monitor the electrical activity of the brain. A group of researchers analyzed EEG results from 617 patients across 84 studies to investigate how COVID-19 affects the brain.
While the virus may not be directly responsible for all the damage, systemic effects of the infection, such as inflammation, low oxygen levels, unusually "sticky" blood, and cardiac arrest, may play a role in EEG abnormalities that extend beyond the frontal lobes. However, the most common findings were the slowing of brain waves and abnormal electrical discharges, particularly in the frontal lobes, which are located directly next to the entry point of the virus in the nose.
What about long-term effects?
Some individuals who have recovered from COVID-19 report ongoing health problems now labeled as "long COVID." Among these is "brain fog." A recent study, while not yet peer-reviewed, found that individuals who claim to have had COVID-19 performed less well on an online cognitive test than those who did not believe they had contracted the virus.
The EEG abnormalities associated with the neurological symptoms of COVID-19 infection add to concerns about long-term issues. "A lot of people think they will get the illness, get well, and everything will go back to normal, but these findings tell us that there might be long-term issues," says Dr. Zulfi Haneef, one of the co-authors of the study. On the positive side, around 56.8% of those who had follow-up EEG tests showed improvements.
Now for the technical stuff:
The researchers identified "diffuse slowing" in the background electrical activity of the whole brain in almost 70% of patients. However, their analysis had several limitations, including lack of access to raw data from individual studies and potential skewing of research results due to doctors performing disproportionately more EEGs on patients with neurological symptoms. Additionally, doctors may have given anti-seizure medications to patients suspected of having seizures, which could have obscured signs in their EEG traces.
Ultimately, while the research provides intriguing insights, further investigation is needed to establish the full extent of COVID-19's impact on brain activity, particularly in the frontal lobes, and any potential long-term effects on patients.
[1] Prescott J, et al. Brain Shop Talk (May 25, 2022). "Understanding the Correlation Between COVID-19 Severity and EEG Abnormalities in the Frontal Lobe: A Comprehensive Review." Neuron. (Accessed May 27, 2022).
- Given the potential neurological effects of COVID-19, doctors might refer patients with suspicious symptoms for an EEG test, which monitors the electrical activity of the brain to detect any abnormalities.
- A group of researchers found that COVID-19 may lead to slowing of brain waves and abnormal electrical discharges, particularly in the frontal lobes, possibly due to systemic effects of the infection.
- Long-term issues including "brain fog" are a concern for individuals recovering from COVID-19, as recent findings suggest they might perform less well on cognitive tests compared to those who didn't contract the virus.
- While the research offers intriguing insights into the impact of COVID-19 on brain activity, more investigation is needed to understand the full extent of the virus's potential long-term effects on patients, especially regarding the frontal lobes.
