COVID-19 Impact on the Brain
Researchers have studied the impact of COVID-19 on the brain. They found that the immune response activates endothelial cells that are responsible for leaking blood vessels and are associated with damage to the brain. These endothelial cells express adhesion molecules that cause platelets to stick together. Tissue samples revealed high levels of these adhesion molecules. The researchers also found that certain genes were expressed in areas of damaged endothelial cells.
olfactory bulb
In a study in hamsters, chronic inflammation of the olfactory bulb was associated with behavioral changes, which were similar to those of people with mood disorders. Although the olfactory bulb tissue of COVID-19 patients is difficult to obtain, the study’s findings suggest a relationship between the inflammatory changes of the olfactory bulb and changes in brain activity. This relationship will require further investigation.
Parahippocampal gyrus
The parahippocampal gyrus is an area of the human brain connected to the olfactory cortex and orbitofrontal cortex. This region plays an essential role in spatial navigation and memory formation. In addition, the hippocampus is also involved in emotional and behavioral reactions. Lesions in this region can lead to poor memory, decreased learning, and even anxiety-depressive and schizoaffective disorders. However, the underlying mechanisms for these changes are not completely understood.
Orbitofrontal cortex
COVID-19 causes significant damage to the primary olfactory cortex, which receives input directly from olfactory receptors in the olfactory bulb. It is the first part of the brain to process odors. In addition, the primary olfactory cortex sends sensory information to the orbitofrontal cortex, which is often referred to as the secondary olfactory cortex.
Cerebral vascular endothelial cells
Cerebral vascular endothelium is the center of inflammation, regulating inflammatory mediators and coagulation factors. When COVID-19 infects brain cells, it can trigger a cytokine storm, activating tissue factor pathways. This causes the endothelium in the microcirculation to become dysfunctional, leading to thrombosis. Ultimately, COVID-19 can lead to ischemic stroke.
Neurologic symptoms
COVID-19 is a virus that can cause neurological symptoms, including strokes. A stroke is a sudden interruption of blood flow to the brain, and it can damage brain cells and lead to disability. COVID-19 can cause strokes in young, otherwise healthy people.
Immune response
COVID-19 may damage brain tissue through its effects on the immune response. It induces an inflammatory cytokine storm that damages the blood-brain barrier and allows inflammatory cells, molecules, and viral particles into the brain. This process can lead to a number of complications, including seizures, coma, and altered mental states.
