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Speaker 1: Welcome to Brainstuff from how Stuff Works dot com where

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Speaker 1: smart Happens. Hi Am Marshall Brain with today's question, how

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Speaker 1: do strokes work? Like strokes that happened inside of people's

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Speaker 1: brains Over the weekend, a video made the rounds on YouTube.

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Speaker 1: The video shows a newscaster named Serene Branson giving a

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Speaker 1: report outside the Grammy Awards. Her first few words are okay,

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Speaker 1: but then what follows is undecipherable. It appears that she's

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Speaker 1: forgotten how to speak and can only link unrelated sounds together.

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Speaker 1: According to early reports, she was quickly rushed to the hospital.

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Speaker 1: Later reports disputed the early reports, and who knows what

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Speaker 1: really happened. But when those early reports came out, the

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Speaker 1: speculation was that she had suffered from a stroke. In

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Speaker 1: a stroke, something goes wrong with the supply to the brain.

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Speaker 1: In Branson's case, it appeared that the blood supply to

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Speaker 1: her speech center was suddenly interrupted. Everyone has heard of

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Speaker 1: a heart attack because heart attacks are the number one

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Speaker 1: killer in America according to the c d C, and

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Speaker 1: most people understand the cause of heart attacks. On the

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Speaker 1: outside of the heart, there are blood vessels that supply

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Speaker 1: oxygen and nutrients to the hearts muscle cells. If one

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Speaker 1: of those blood vessels gets clogged, either with plaque or

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Speaker 1: with a blood clot, part of the heart muscle runs

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Speaker 1: out of oxygen and starts dying. A stroke is the

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Speaker 1: same kind of thing that happens in the brain, cutting

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Speaker 1: off oxygen to an area of the brain and causing

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Speaker 1: brain cells to start dying. Strokes are currently the number

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Speaker 1: three cause of death in the United States. Strokes are

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Speaker 1: categorized by the way in which the blood supply is interrupted.

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Speaker 1: In the most common type of stroke, something blocks in artery.

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Speaker 1: The two things that can blow an artery in the

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Speaker 1: brain are the same two things that can block an

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Speaker 1: artery in the heart, either plaque or a blood clot.

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Speaker 1: Plaque is a fatty substance that builds up on the

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Speaker 1: inside of arteries, slowly filling them and shrinking the amount

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Speaker 1: of blood that can flow. If enough plaque builds up,

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Speaker 1: it cuts off blood flow completely and causes a stroke.

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Speaker 1: This is the most common way to have a stroke.

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Speaker 1: Blood clots are less likely than plaque, but they have

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Speaker 1: exactly the same effect. One advantage of a stroke caused

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Speaker 1: by a blood clot is that clots can sometimes be

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Speaker 1: dissolved with clot busting drugs. If dissolved quickly enough, the

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Speaker 1: brain can sometimes recover. The other type of stroke is

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Speaker 1: a hemorrhagic stroke, and here there's a rupture instead of

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Speaker 1: a blockage. One of the blood vessels inside the brain

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Speaker 1: breaks and starts bleeding. This can not only cut off

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Speaker 1: the blood supply, but may also cause pressure on parts

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Speaker 1: of the brain from the blood that escapes. The rupture

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Speaker 1: can come from an aneurysm, a thin part of a

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Speaker 1: larger blood vessel that pops like a balloon, or a rupture,

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Speaker 1: and a small blood vessel often triggered because blood pressure

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Speaker 1: is too high. Once a stroke occurs, there are a

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Speaker 1: number of telltale signs that may appear. A sharp, sudden

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Speaker 1: headache that comes out of nowhere is one of the

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Speaker 1: classic signs. Slurred speech, as in the case of Serene Branson,

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Speaker 1: is another. A sudden inability to understand or respond to

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Speaker 1: spoken commands usually indicates a stroke as well. If a

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Speaker 1: limb suddenly goes numb or goes limp or it looks

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Speaker 1: like the muscles on one side of the face have

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Speaker 1: stopped working, that would be another classic sign of a stroke.

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Speaker 1: Strange sudden vision problems would be another. The place where

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Speaker 1: the stroke occurs controls the symptoms. For example, if the

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Speaker 1: stroke occurs near the part of the brain that controls

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Speaker 1: the right arm, then the right arm will go limp.

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Speaker 1: There are something like seven hundred thousand strokes in the

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Speaker 1: United States every year. They are fairly common events, especially

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Speaker 1: in older adults. If you're visiting with a friend who

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Speaker 1: suddenly manifests strange symptoms like those described above, time is

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Speaker 1: of the essence. The quicker a stroke is treated, the

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Speaker 1: better the chances of recovery. Call nine one one immediately

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Speaker 1: and keep the person having the stroke calm until help arrives.

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Speaker 1: For more on this and thousands of other topics, does

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Speaker 1: that how stuff works dot com and don't forget to

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