In an interview on ABC's "Dancing with the Stars" Monday (Oct. 9), actor Frankie Muniz revealed he's had "a fair amount of ministrokes."
Muniz brought up the ministrokes while discussing problems with his memory, according to People magazine.
"I have had nine concussions and I've had a fair amount of mini-strokes … I'm not saying those things correlate exactly to the reason why my memory's not great," Muniz said. He's had an estimated 15 ministrokes, the People magazine article added. [Strange Stroke Stories: Ebola, Hickeys and Other Weird Causes]
But what are ministrokes? And do they have lasting effects?
A ministroke, or "transient ischemic attack" (TIA), occurs when a blood clot briefly blocks blood flow to a part of the brain, according to the Mayo Clinic. A TIA is similar to an ischemic stroke, but during an ischemic stroke, the blockage lasts longer, leading to permanent brain damage. In both cases, the blockages are often caused by the buildup of plaque in a blood vessel.
The symptoms of a TIA are also similar to those of an ischemic stroke, which is the most common type of stroke, the Mayo Clinic says. During a TIA, a person might experience symptoms such as weakness, numbness or paralysis on one side of the body, slurred or garbled speech, blindness in one or both eyes or double vision, dizziness or loss of balance, or a sudden, severe headache with no known cause.
Unlike a stroke, however, a TIA usually doesn't lead to permanent brain damage, according to the Mayo Clinic. This is because in the case of a TIA, the body gets rid of the blockage in the blood vessel before it causes lasting damage, according to the American Stroke Association (ASA). Once the clot is gone, blood flow returns; the longer blood flow is blocked, the more likely there will be permanent damage. (If a TIA-causing clot doesn't go away, it is classified as an ischemic stroke.)
Still, it's essential to seek medical attention if you experience stroke-like symptoms. It's not possible to tell if a person is having a full-blown stroke or a TIA based on symptoms alone, the Mayo Clinic says. In some cases of stroke, the symptoms may seem to go away, for example.
Though a TIA is often referred to as a ministroke, the ASA says a more accurate term is "warning stroke." This is because a TIA can be a sign that a person will have a full-blown stroke in the future. More than 10 percent of people who have a TIA go on to have a full-blown stroke within three months, and half of these strokes occur with 48 hours of the TIA, according to the National Library of Medicine.
In addition, about 1 in 3 people who have had a TIA go on to have a stroke within one year, and up to 40 percent of people who have had an ischemic stroke report that they had a TIA first, the ASA says.
Once a person has had a TIA, he or she is more likely to have another one, according to the Mayo Clinic.
If you think you're having a stroke, call 911 immediately.
Originally published on Live Science.