Scientists Say Long COVID-19 Can Cause Brain Fog

Illustration of brain fog. (Pexels)

JAKARTA - In the latest study, scientists revealed that the long effect of COVID-19 is indeed true and can cause a brain fog or brain fog. Long COVID-19 is a prolonged symptom of the virus, although it has long been declared negative.

In the UK, it is estimated that 1.9 million people live with long COVID, which has symptoms such as fatigue, shortness of breath, and joint pain. One of the most weakened effects is brain blurring.

Brain fog or brain fog is a cognitive problem, such as poor memory, thinking slower, focusing difficulties, affecting more than 80 percent of people who have been infected with COVID-19.

In a recent study published in Brain Communications, scientists are spying on AMPAR receptors, proteins on the surface of brain cells that help transmit signals involved in learning and memory.

abnormal activity in AMPAR was previously associated with conditions such as depression, bipolar disorder, and dementia. By using advanced brain scans, the researchers compared 30 long-term COVID-19 patients with 80 healthy volunteers and found significant increase in AMPAR's activity, among those with cognitive symptoms.

The more severe the brain fog occurs, the denser the receptor's activity. This shows a clear biological relationship with COVID-19 in the long term.

"Our findings clearly suggest long-term COVID-19 brain fog should be recognized as a legitimate clinical condition," said professor Takuya Takahashi, a molecular mechanism expert and study co-author, quoted by the Daily Mail, on Thursday, October 9, 2025.

The findings confirm its connection as a potential target for future medicine. It also encourages the healthcare industry for treatment development.

"This can encourage the healthcare industry to accelerate the development of diagnostic and therapeutic approaches for this disturbance," concluded Takuya.