The symptoms of a stroke are sometimes obvious, like numbness or weakness on one side of the face, trouble speaking, difficulty walking, and vision problems. Silent strokes, though, pass completely unnoticed. But even these can have a significant and lasting effect on memory, reports the June 2012 issue of the Harvard Women’s Health Watch.

These so-called silent strokes create pinpoints of dead cells in the brain. The damaged areas are smaller than with a traditional stroke, and often don’t affect areas of the brain associated with movement or speech.

During a typical ischemic stroke, a blood clot blocks a blood vessel that feeds part of the brain. Without a steady supply of blood, cells in that area malfunction and may die. Symptoms that appear reflect the functions that were controlled by the affected part of the brain. A hemorrhagic stroke caused by a burst blood vessel does the same thing.

During a silent stroke, the interruption in blood flow occurs in part of the brain that doesn’t control any vital functions.

Although it doesn’t cause any obvious symptoms—most people who’ve had a silent stroke have no idea it occurred—the damage does show up on an MRI or CT scan.

Silent strokes could interrupt the flow of information in the brain needed for memory, especially if several of these strokes occur over time (which is the most common scenario). Damage from silent strokes can accumulate, leading to more and more memory problems.

Is there anything a woman can do when faced with a stroke that has no symptoms, and that can only be found on an MRI or CT scan? “I think that it should make people aware that it’s imperative to manage risk factors,” says Karen Furie, associate professor at Harvard Medical School and director of the Massachusetts General Hospital Stroke Service. This means:

  • controlling blood pressure and diabetes
  • not smoking
  • keeping cholesterol levels in check
  • aiming for a healthy weight
  • managing atrial fibrillation

If you are experiencing signs of memory loss, don’t dismiss it as a normal part of aging. See your doctor for testing to make sure the issue isn’t a silent stroke.

Preventing memory loss from silent strokes

The good news is that silent strokes are a preventable form of memory loss.

To avoid silent strokes and protect your memory, follow these lifestyle tips:

  • Control your blood pressure by getting it checked regularly and taking blood pressure medicine, if you need it.
  • Limit salt to less than 1 teaspoon per day and follow the DASH eating plan, which has been shown to lower blood pressure about as much as medication in some people. (To learn more about this diet, visit: www.dashdiet.org/)
  • Aim to keep your total cholesterol levels below 200 mg/dL, and your LDL cholesterol below 100 mg/dL. To help lower your cholesterol, lose weight if you’re overweight, consume less than 200 milligrams of cholesterol daily, and increase the fiber in your diet (20 to 30 grams of fiber each day is ideal).
  • Quit smoking. Smoking more than doubles your risk of a stroke. Talk to your doctor about nicotine-replacement products such as patches and gums, and medicines to help you quit.
  • Watch your weight. Aim for a body mass index between 19 and 25 (calculate your BMI at www.nhlbisupport.com/bmi).
  • Eat at least 1.5 cups of fruit and 2.5 cups of vegetables a day and cut back on foods like red meat and sweets to keep your weight within a healthy range.
  • Play tennis, swim, ride a bike, or take a brisk walk for 30 minutes a day, at least five days a week. A 2011 study in the journal Neurology found that getting regular, moderate to intense exercise can cut your risk of a silent stroke by 40 percent. 

Read the full-length article: “Could a silent stroke erode your memory?”