Skip to content

    Brain & Nervous System Health Center

    Font Size

    1-Minute Sideline Test Predicts Concussions

    After Blow to Head, Eye Test Tells Whether Player Should Stay in Game
    WebMD Health News
    Reviewed by Laura J. Martin, MD

    Feb. 4, 2011 -- Should Green Bay Packers quarterback Aaron Rodgers have stayed in a crucial playoff game after taking a violent blow to the head?

    A Super Bowl berth was the ultimate outcome. But had Rodgers taken a new one-minute concussion test on the sidelines, his coaches would have known whether he was at risk of a far worse outcome: serious brain damage.

    The test is simple. Before the game, a coach or trainer shows each athlete a set of three index cards. Each card has a series of numbers scattered across eight lines. The athlete reads the numbers from left to right.

    After a blow to the head, the athlete goes to the sidelines and retakes the test. If he's five seconds slower, he may have suffered a concussion -- and is at serious risk if his head gets hit again.

    It sounds too simple to be true, especially because only the most sophisticated brain scans can detect many concussion effects.

    But it turns out that eye movement is strongly linked to neurological function. The simple test, called the King-Devick or K-D test, shows whether eye movement is impaired. If so, it's likely that the athlete has suffered a concussion.

    Concussion Test ID's Brain Damage Risk

    A single, first-time concussion often heals without incident. But before it heals, it makes a person extremely vulnerable to brain damage from a second head trauma.

    It's not a small problem. It's estimated that every season, one in five U.S. athletes in a contact sport suffers a concussion. A second concussion can be very bad news indeed. And athletes hit in the head may suffer brain injury even if not diagnosed with concussion.

    About 17% of boxers, for example, develop a form of dementia called chronic traumatic encephalopathy (CTE). CTE also affects athletes in other contact sports such as football, soccer, and hockey. Symptoms, which can be disabling, include chronic headaches, fatigue, sleep difficulties, sensitivity to light and noise, dizziness, and short-term memory loss.

    "Concussion is a complex type of brain injury that is not visible on the routine scans we do of the brain, yet is detectable when we measure important aspects of brain function, such as vision," study researcher Kristin Galetta of the University of Pennsylvania says in a news release.

    Today on WebMD

    nerve damage
    Learn how this disease affects the nervous system.
    senior woman with lost expression
    Know the early warning signs.
    woman in art gallery
    Tips to stay smart, sharp, and focused.
    medical marijuana plant
    What is it used for?
    woman embracing dog
    boy hits soccer ball with head
    red and white swirl
    marijuana plant
    brain illustration stroke
    nerve damage
    Alzheimers Overview
    Graphic of number filled head and dna double helix