By GERALD TRAMONTANO
Published: September 12, 2008
Mount Arlington, N.J

CHILDREN aged 5 to 18 suffer at least 96,000 sports-related concussions every year in the United States, the Centers for Disease Control and Prevention estimates. Even more troubling, as many as 20 percent of all high school football players sustain concussions annually, studies show. Because teenage brain tissue is still developing, injuries at this age can be especially damaging. Yet most high schools and colleges fail to provide athletes the kind of neuropsychological testing that’s needed to help them recover.

It’s true that coaches have become better educated about concussions. The days of patting the athlete who’s had his "bell rung" on the backside and sending him back into the game are diminishing. Most now realize that someone who’s had a concussion needs rest. He or she may need to take a break from the sport, or even from school. This allows the brain to devote all its resources to healing.

Without rest, the victim risks developing post-concussion syndrome, which can include not only headaches, dizziness and nausea but also a loss of memory, difficulty paying attention, fatigue, mood swings and personality changes — symptoms that in some cases last a lifetime.

But how can you tell how much rest is needed? It’s not enough to simply wait until the "fog clears" or even have the athlete take a cautionary week or two off. And while it’s helpful to ask the athlete if he feels well enough to play, this is also not a reliable way to assess whether he is ready. Players, whether they are high school athletes or professionals like the New York Mets outfielder Ryan Church, who developed post-concussion syndrome earlier this season, often want to get back to the game prematurely.

Even imaging tests like M.R.I.’s or CT scans cannot reveal when the athlete has had enough rest, because they are not sensitive enough to detect the kind of microscopic damage to brain cells and brain chemistry that concussions can cause.

The only way to know for sure whether a concussion victim’s brain has returned to normal is to compare the results of neuropsychological tests conducted before and after the injury. That requires preparing athletes for the season by putting them through baseline testing.

Schools have generally been slow to adopt this testing. Their reluctance probably has to do with the cost, as much as $1,000 per test. But because the tests can remove the guesswork in determining whether someone is ready to return to the field, they are an essential piece of protective equipment for athletes.

Baseline testing typically consists of two two-hour batteries of tests. They include assessments of the patient’s motor skills, reaction time, attention span, vision, hearing, sense of taste, memory and psychological characteristics like moodiness and depression — all characteristics that might change after a head injury. Often included are a smell identification test, a grip strength test and a test in which patients watch a computer screen and click a button when a target flashes by. That measures reaction time, attention span and the ability to control one’s emotions and impulses.

The baseline evaluation also includes a medical history, which helps determine the athlete’s future risk of head injury and his long-term prognosis in the event of a concussion. At greatest risk for post-concussion syndrome are people who have had concussions before, have a family member with a psychiatric disorder or have a condition like attention deficit hyperactivity disorder, seizures or bipolar disorder. Also, the risk is greater for females than for males.

A brain injury can do lasting damage to neurons and arteries and alter brain chemistry, too. That can reduce a patient’s ability to concentrate or cope with frustration, and lead to moodiness, irritability and depression. Such impairments make it more difficult to deal with daily stresses, and thus often lead to significant social problems.

To fully recover from a concussion, the brain must quickly reorganize itself and enlist other neurons to take over the work of those that have been damaged. This can take three months or more. The only reliable way to gauge when healing is complete is to give the patient another set of neuropsychological tests and see whether the scores match the baseline results. If they do not, the patient may need cognitive rehabilitation therapy before the test is administered again.

That assumes, of course, that baseline scores are available. Protecting athletes starts with taking the proper precautions before an injury occurs.

Gerald Tramontano is a clinical neuropsychologist.

A version of this article appeared in print on September 13, 2008, on page A19 of the New York edition.