Brain's frontal lobe electrical activity can be disrupted due to COVID-19
Research is shedding light on the impact of COVID-19 on the brain, particularly in those with neurological symptoms. According to studies, approximately 15-25% of severe COVID-19 cases may exhibit such symptoms, including headaches, confusion, delirium, and seizures[1].
As a result, doctors may refer patients experiencing these symptoms for EEG tests. These tests involve placing electrodes on the scalp to monitor the electrical activity of the brain[1].
To gain insights into how COVID-19 affects the brain, researchers analyzed Electroencephalography (EEG) results from 617 patients, derived from 84 different studies. They found that the most common abnormalities were slowing of brain waves and irregular electrical discharges[1].
Interestingly, around a third of these abnormalities were located in the frontal lobes of the brain. Dr. Zulfi Haneef, one of the co-authors of the study, suggests that this could be related to the fact that the virus typically enters the body through the nose, which is closest to the frontal lobes[1].
Concerningly, the extent of these EEG abnormalities often correlates with the severity of the disease and the presence of pre-existing neurological conditions[1]. However, it's essential to note that the virus may not be directly responsible for all the damage. Other factors, such as inflammation, low oxygen levels, and cardiac arrest, may also contribute[1].
The study also revealed "diffuse slowing" in the background electrical activity of the whole brain in nearly 70% of patients[1].
Recovered patients have reported ongoing health problems, collectively referred to as "long COVID." Among these is "brain fog." A recent study found that individuals who claim to have contracted COVID-19 performed less well on an online cognitive test than those who did not believe they had the virus[2].
This suggests that the infection may have an aging effect on the brain. The authors of the study concede that this cross-sectional study does not prove that the infection caused long-term cognitive decline, but it highlights concerns about potential lasting effects on the brain[2].
Dr. Haneef notes that the findings of EEG abnormalities associated with the neurological symptoms of COVID-19 infection add to these concerns[2]. He adds, "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, which is something we have suspected, and now we are finding more evidence to back that up."
On a positive note, around 57% of patients showed improvements during follow-up EEG tests[1]. However, the study had limitations, such as a lack of access to raw data from individual studies, the potential omission of normal EEGs, and the use of anti-seizure medications that may have obscured signs of seizures in EEG traces[1].
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[1] Estimates vary, but approximately 15-25% of patients with severe COVID-19 may experience neurological symptoms, such as headaches, confusion, delirium, impaired consciousness, seizures, and strokes. [Research data]
[2] Some people who have recovered from COVID-19 report ongoing health problems, now labeled long COVID. Among these is "brain fog." A recent study (now on preprint server MedRxiv) 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, potentially suggesting an aging effect on brain function. [Research data]
- The study found that EEG abnormalities, such as slowing of brain waves and irregular electrical discharges, are commonly seen in COVID-19 patients and are often linked to the severity of the disease and the presence of pre-existing neurological conditions.
- Some patients with severe COVID-19 may experience neurological symptoms, including seizures, and doctors often refer them for EEG tests to monitor the electrical activity of the brain.
- The ongoing health problems often reported by recovered COVID-19 patients, collectively known as "long COVID," may include "brain fog," which could potentially suggest an aging effect on the brain, according to a recent study.
