This Is What Having a Stroke Does to Your Brain

Stroke symptoms strike suddenly, but the effects can be long-lasting.

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Every 40 seconds someone in the United States suffers a stroke, according to the Centers for Disease Control and Prevention (CDC). That amounts to 795,000 people each year, on average. And it’s not just older adults: Stroke can happen to people in their twenties or thirties too.

Stroke can happen in an instant, but can leave lasting damage that can permanently impair a patient’s quality of life. In fact, stroke is the leading preventable cause of long-term disability in the U.S., according to the American Stroke Association (ASA).

What Exactly Is a Stroke?

Knowing what a stroke does to your brain and body can clarify why it’s so destructive. Essentially, “a stroke is an injury to the brain,” says Carolyn Brockington, MD, neurologist at Mount Sinai Hospital. “The injury is caused from an interruption of blood flow suddenly.”

Arteries throughout your body transport blood to each of your organs, which helps deliver oxygen and nutrients to all the cells in your body. Health concerns like high blood pressure, high cholesterol, and heart disease can block or harden arteries, which can cause a variety of problems throughout the body as your organs receive less oxygen from your blood.

But the brain is needy when it comes to oxygen; it requires about 20 percent of your body’s oxygen supply. Some organs may be able to get by with insufficient blood flow for a while, but when a part of the brain loses its crucial oxygen supply, the consequences can be instant and devastating.

What Are the Symptoms of a Stroke?

Since multiple arteries supply the brain with oxygen, and a stroke usually occurs in one specific artery, a stroke typically takes place in just one region of the brain. As a result, stroke symptoms may vary based on where in the brain the stroke occurred.

The left side of the brain generally controls the right side of the body, and vice versa. “So let’s say someone doesn’t get enough blood flow to the right side of their brain. Suddenly they’re going to have symptoms [on the left side of the body],” says Dr. Brockington.

Symptoms of a stroke can include:

  • Drooping face, especially on one side of the body

  • Weak or drooping arm or leg, especially on one side of the body

  • Blurry vision

  • Trouble with language, speech, and communication

Learn more signs of stroke here.

“The important thing is to realize is that the symptoms begin abruptly,” says Dr. Brockington. “Almost like pulling the plug out [and] suddenly the computer goes off. It’s the same with the brain.”

What Are the Main Types of Stroke?

The majority of strokes are ischemic strokes, which comes from the Greek word iskhaimos, or “stopping blood.” An ischemic stroke is usually a result of a blocked blood vessel or blood clot.  Ischemic strokes account for more than 80 percent of strokes that occur, according to the ASA.

The remaining strokes are hemorrhagic strokes, which means bleeding is happening in the brain. This usually stems from a ruptured blood vessel, which could be caused by high blood pressure, bleeding disorders, or head injuries, according to the National Stroke Association.

What Happens to the Brain After a Stroke?

Although the injury caused by stroke is permanent, the good news is that the brain has the ability to recover.

Surprisingly, the damaged part of the brain is not what recovers after a stroke. “It is the area that surrounds the injured area that makes new connections between itself to do what this part of the brain used to do,” says Dr. Brockington.

Rehab after stroke can stimulate the brain to make these new connections and improve long-term quality of life. But quick treatment is crucial, both in terms of emergency medical treatment as the stroke is happening, and ongoing rehabilitation following the stroke.

“In stroke treatment, we say ‘time is brain,’” says Dr. Brockington. “What we mean by that is that every moment that goes by, there are a million brain cells that die.” That’s why doctors use the acronym F-A-S-T to recognize stroke symptoms to encourage prompt treatment.

By shortening the length of time the stroke goes untreated, you can reduce the degree of damage to the brain,  which makes recovery more successful. Patients who arrive to the ER within three hours of the start of the stroke experience fewer deaths, greater recovery, and less disability than those who have delayed treatment, according to the CDC.

If you are having a stroke or see someone having a stroke, don’t drive yourself to the hospital. Find out why calling an ambulance is also crucial for stroke recovery.