Inflammation is the body’s natural response to injury or illness. Neuroinflammation happens when an illness, injury, or other issue causes inflammation within the nervous system. Inflammation in the brain and spinal cord occur with many brain diseases and disorders, particularly autoimmune and degenerative ones.

High levels of neuroinflammation may accelerate brain aging and contribute to the progression of certain brain diseases. For example, it may be a major component of the symptoms and progression of Parkinson’s disease. And multiple sclerosis (MS) is also characterized by an inflammatory process along with the loss of the structure and function of neurons, known as neurodegeneration. Finally, research on brains affected by Alzheimer’s disease has shown that an increase in inflammation can also contribute to neurodegeneration.

Inflammation can also play a positive role in brain health. Whether neuroinflammation is beneficial or not depends on context, intensity, and duration. For example, if the brain experiences tragedy or trauma, an inflammatory response helps drive repair processes. It helps promote immune conditioning and neuroplasticity, which is the brain’s ability to alter connections, after an injury. But if the inflammation goes on for too long, it can cause damage.

Understanding neuroinflammation better can help researchers and doctors know where, when, and how to increase or decrease inflammation within the central nervous system. Being able to regulate inflammation in this way could lead to improved treatments for many different brain diseases.