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What grey
matter and lesions

mean when it comes to MS

There are two types of brain matter

The brain is made up of two types of tissue: grey matter, which is where communication signals start, and white matter⁠—which carries messages from one area to another. Multiple sclerosis (MS) lesions occur in both of these areas and can lead to the symptoms you experience.

Lesions on grey and white matter scheme

What we now know about the role of grey matter

For many years, researchers focused primarily on white matter when it came to MS. And while white matter is important (about 95% of all MS lesions happen there), recent research has revealed that lesions and a decrease in grey matter (also known as brain volume loss) can have a much greater impact on MS than once believed.

Lesions on grey and white matter scheme
Brain MRI icon

Grey matter lesions can happen early on

MS lesions can happen in both white matter and grey matter. But grey matter lesions
can start very early in the disease⁠—even before you experience symptoms.

Symptom progress in MS icon

The progression of MS can be tied to grey matter lesions

Lesions in both the white matter and grey matter of the brain can lead to the symptoms you experience. However, changes in grey matter, such as those caused by lesions, may be more closely associated with a decline in physical ability and cognitive changes (which can include worsening memory, difficulty concentrating, or trouble thinking of the right word) than white matter lesions.

Losing grey matter chart

Decreases in the volume of grey matter can help predict long⁠-⁠term disability

As we age, we all lose brain volume naturally. For people with MS, this can happen more quickly. That’s because lesions in both grey and white matter can become scar tissue, which causes the volume of the brain to decrease. A decrease in the volume of grey matter is a strong predictor of long⁠-⁠term physical disability and cognitive issues in MS.

Lesions can change over time

Lesions often progress over time. That’s why identifying them early, and monitoring them regularly, are important. This progress is monitored by using magnetic resonance imaging (MRI) scans. These scans produce three kinds of images.


GdE lesions on MRI example


Lesions begin as inflammation.

These are called GdE (gadolinium‑enhancing) lesions.
In the GdE MRI, a liquid dye is injected into the body to make areas of inflammation visible.


T2 lesions on MRI example


If inflammation persists, it can lead to new lesions or cause existing lesions to evolve.

These are called T2 lesions. They show up as “bright white spots” on an MRI.


T1 lesions on MRI example


Over time, lesions can mature—becoming permanent scars in the brain.

These are T1 lesions. They appear as dark areas or “black holes” on an MRI.

Neurological reserve icon

Neurological reserve:
How the brain can adapt to lesion damage

When brain lesions occur, the affected area may no longer function properly. However, other areas can step in and perform the tasks that part of the brain no longer can. This amazing ability to adapt is called “neurological reserve.”

Neurological reserve can keep you from experiencing symptoms of MS early on. However, this ability doesn’t last forever. It’s important to make healthy lifestyle choices to help maintain neurological reserve for as long as you can. It’s part of what a brain-first perspective of MS is all about.