Brain's Frontal Lobes Electrical Activity Potentially Affected by COVID-19
Approximately 15-25% of patients with severe COVID-19 may experience neurological symptoms, including headaches, confusion, delirium, impaired consciousness, seizures, and strokes. In an attempt to understand the impact of COVID-19 on the brain, researchers analyzed EEG results from 617 patients, reports from 84 different studies.
The research, published in the journal Seizure: European Journal of Epilepsy, found that slowing of brain waves and abnormal electrical discharges were the most common findings. The extent of the EEG abnormalities positively correlated with the severity of the disease and the presence of preexisting neurological conditions, such as epilepsy.
Around a third of the abnormal findings were in the frontal lobes of the brain. Dr. Zulfi Haneef, assistant professor of neurology/neurophysiology at Baylor, suggested that this could be linked to the virus's most likely entry point being the nose, located next to the frontal lobes. Further investigation, he suggested, should take the form of wider EEG testing, as well as other types of brain imaging, such as MRI or CT scans, to provide a closer look at the frontal lobe.
However, it's important to note that 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.
The study also identified "diffuse slowing" in the background electrical activity of the whole brain in almost 70% of patients. Some people who have recovered from COVID-19 report ongoing health problems, now labeled "long COVID." Among these is "brain fog."
A recent study found that individuals who claim to have had COVID performed less well on an online cognitive test than those who did not believe they had contracted the virus. This study does not prove that the infection caused long-term cognitive decline, but it does highlight concerns about lasting effects on the brain. Dr. Haneef noted that this adds to these concerns, as there may be long-term issues for COVID-19 patients.
On the positive side, the authors report that 56.8% of those who had follow-up EEG tests showed improvements. They note that their analysis had several limitations, including lack of access to raw data from individual studies and potential skewing of results due to doctors performing disproportionately more EEGs on patients with neurological symptoms. Doctors may also have given anti-seizure medications to many patients, potentially obscuring signs of seizures in their EEG traces.
Further research will be necessary to fully understand the correlation between COVID-19 severity and EEG abnormalities in the brain. However, this research emphasizes the importance of EEG as a tool to monitor neurological impact and severity in COVID-19 patients, reflecting the brain's functional state in the context of systemic and central nervous system involvement by the virus.
- The study on COVID-19 and its impact on the brain, published in the journal Seizure: European Journal of Epilepsy, also highlighted epilepsy seizures as one of the neurological symptoms observed in some patients.
- Beyond the frontal lobes, the systemic effects of COVID-19, such as inflammation, low oxygen levels, and cardiac arrest, may contribute to EEG abnormalities in other areas of the brain, potentially leading to health-and-wellness issues like "brain fog."
- The researchers findings suggest that EEG tests could be a crucial tool for monitoring the neurological impact and severity of COVID-19 in patients, given its ability to reflect the brain's functional state amidst systemic and central nervous system involvement by the virus, thus contributing to the field of health-and-wellness, medical-conditions, science, and neurological-disorders studies.
