What’s the Link Between MS and Brain Fog?

Multiple sclerosis (MS) is an autoimmune disease that attacks healthy cells in the brain and spinal cord. There are many symptoms of MS, one of which is brain fog - difficulty with memory, concentration, and brain function.

Learn more about MS brain fog, including what causes it, how to deal with it, and more.

MS symptoms can involve brain fog and confusion

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What Is Brain Fog?

Brain fog, sometimes called cog fog, is a term that describes some of the cognitive symptoms of MS and other medical conditions that affect brain function.

Symptoms of brain fog may include difficulties related to thinking and brain function, such as:

  • Confusion and decision making
  • Memory, attention, and concentration
  • Understanding, processing, and thought delays
  • Planning and disorganization

Cognitive symptoms affect roughly 45% to 60% of people with MS.

What Causes Brain Fog in Multiple Sclerosis?

Brain fog can be a symptom of MS for several reasons.


MS can cause lesions (spots or scars that show damaged cells) in the brain that can affect cognitive abilities and cause brain fog. These spots can be seen on magnetic resonance imaging, or MRI images, and are used to help diagnose MS.

Areas of the Brain Affected

The brain consists of white matter and gray matter, and both play a vital role in overall body function: Gray matter is the outermost layer of the brain and helps with the processing required for daily functioning. White matter is farther from the surface and serves as a link between gray matter and the rest of the body; it sends messages and communicates with the rest of your body.

Myelin is a coating that protects the nerves in the brain and spinal cord, and speeds up the messaging from your brain to other body parts, and gives the white matter its white hue. MS occurs when the immune system attacks myelin, causing it to deteriorate. The damage to the brain caused by MS tends to primarily affect the white matter since it has more myelin, but the gray matter can also be affected.

Damage to different brain areas can lead to cognitive symptoms such as confusion and memory challenges that people call brain fog.

Nerve Definition

Nerves are cells that are responsible for communicating between the brain and other parts of the body.

How to Deal With It

The cognitive symptoms of MS can be challenging and severe enough to impact daily life and functioning. However, there are things people with MS brain fog can do to minimize symptoms and prevent it from negatively impacting life.

Tips for living with MS brain fog include:

  • Talk about it. Discuss your cognitive symptoms and brain fog with your healthcare provider so they can help. These challenges are effects of MS, just like the physical symptoms.
  • Learn about it. There are resources available specifically for MS-related cognitive challenges, including research and educational material. Knowing more about MS can lead to finding solutions that can help.
  • Support mental and emotional health. Mental and emotional challenges such as stress, depression, and anxiety can worsen cognitive symptoms. Finding support and treatment for mental and emotional difficulties can help you cope.
  • Lean on family and friends. It can help to have friends and family members come with you to appointments and help manage daily tasks, such as reminding you to take medications.
  • Use tools and processes. Alarms, apps, and planners can help you stay on track with organization and reminders to ensure you follow your treatment plan.

Lifestyle Changes

In addition to general coping strategies for MS brain fog, some lifestyle changes can help.

  • Diet. No specific diet plan is recommended for MS, but research has shown that focusing on vegetables and fruits and not overeating can help. Additionally, omega-3 fatty acids, found in foods like flax seeds, chia seeds, walnuts, and avocados, have been shown to help.
  • Exercise. Regular exercise, three times per week, has been shown to improve cognitive function in people with MS.
  • Intellectual enrichment. Brain exercises, such as puzzles, crafts, or activities, can challenge the brain and keep it nimble. While this may not reverse cognitive decline, it has been shown to prevent or slow future decline in people with MS.


Multiple sclerosis, or MS, is a lifelong disease that happens when the immune system attacks healthy cells in the brain and spinal cord. Brain fog, also called cog fog or cognitive decline, is a group of symptoms related to brain function. This may include memory loss, confusion, slowed thinking, and more.

Brain fog may occur as a symptom of MS due to damage to the myelin in the brain. This damage can be seen as lesions on MRI scans. People with MS can cope with brain fog and prevent it from worsening by eating a healthy diet with omega-3-rich foods, exercising regularly, seeking support, and using alarms and planners to stay on track with treatment.

A Word From Verywell

Experiencing brain fog and other symptoms of MS can be challenging and life-changing. Help is available, and there are ways to cope. If you or someone you know is experiencing brain fog associated with MS, reach out to a healthcare professional, such as a primary care healthcare provider or neurologist, for support.

Frequently Asked Questions

  • Do autoimmune diseases cause brain fog?

    Brain fog is a symptom of many autoimmune diseases, including MS. The link between autoimmune diseases and brain fog is not entirely understood, but some research points to inflammation, or swelling, playing a role.

  • Does brain fog in MS go away?

    No, MS brain fog does not go away. It often stays the same or may worsen over time. However, it may come and go, and there are things people with MS can do to improve brain function or prevent it from getting worse.

  • Do brain MRIs detect multiple sclerosis lesions?

    MRIs of the brain can detect lesions caused by multiple sclerosis and help to diagnose MS. However, no test is perfect, and an MRI can miss them.

  • What cognitive symptoms do people with MS have?

    People with MS may experience cognitive symptoms such as difficulty with memory, concentration, decision-making, and thinking.

12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Ashley Olivine, Ph.D., MPH
Dr. Ashley Olivine is a health psychologist and public health professional with over a decade of experience serving clients in the clinical setting and private practice. She has also researched a wide variety psychology and public health topics such as the management of health risk factors, chronic illness, maternal and child wellbeing, and child development.