A key component of the campaign is educating bystanders — family members, co — workers, friends-who may be the first to recognize a stroke in progress.

"Stroke is an unmistakable event," said John R. Marler, M.D., associate director for clinical trials at NINDS. "Few other medical conditions come on so suddenly or are so noticeable to a bystander. The sooner the stroke is recognized and the patient begins receiving treatment, the better are the chances for a complete recovery."

Because stroke injures the brain, the person having the stroke may not be able to recognize the symptoms and take action. An alert bystander can help a stroke patient get to the hospital quickly enough to receive treatments that can drastically reduce disability caused by stroke. A breakthrough study by NINDS found that stroke patients who received t-PA within 3 hours of their initial symptoms were at least 30 percent more likely to recover with little or no disability. t-PA dissolves the clots that cause most strokes.

"It is really worth the effort it takes to call 911," said Dr. Marler. "Treating stroke as an emergency pays back in terms of going home and living your life."

Stroke is the third leading cause of death in the United States and a leading cause of serious, long-term disability. Approximately 600,000 new strokes are reported in the United States annually and about 160,000 Americans die each year from stroke.

Stroke symptoms appear suddenly:

• Sudden numbness or weakness of the face, arm, or leg (especially on one side of the body)

• Sudden confusion or trouble speaking or understanding speech

• Sudden trouble seeing in one or both eyes

• Sudden trouble walking, dizziness, or loss of balance or coordination

• Sudden severe headache with no known cause

The Know Stroke: Know the Signs. Act in Time campaign is being launched in May as part of National Stroke Awareness Month and includes community education materials including a video, brochures, and posters. NINDS is distributing the materials to hospitals, assisted living facilities, senior communities and other settings so that local communities can host stroke educational events. The campaign messages will be seen on billboards, bus shelters, and airport dioramas across the country, and will be aired in radio public service announcements. The materials graphically depict the symptoms of stroke as highway signs, an effort to call special attention to their unique, sudden nature.

The NINDS, a component of the National Institutes of Health, is the nation's leading supporter of research on the brain and nervous system. The NINDS is now celebrating its 50th anniversary.

This release will be posted on EurekAlert! at http://www.eurekalert.org and on the NINDS website at http://ninds.nih.gov/news_and_events/index.htm.