CONCUSSION: A heightened respect
Not so long ago, once the confusion, amnesia, dizziness, and nausea from a concussion subsided, the child went back to school, the athlete returned to play, the soldier was sent again into battle. But concussions are no longer being treated quite so lightly, given a growing body of evidence that "mild" traumatic brain injury can result in serious disabilities and fatalities. When the gelatinous brain is subjected to acceleration-deceleration and rotational forces, the metabolism of brain cells is upset and they can no longer function. And it turns out that "second impact syndrome," or a second concussion before the first has had a chance to heal fully, creates a significantly greater risk of dying. Those who survive face long-term consequences. Indeed, they may eventually suffer from the one form of dementia that's entirely preventable. Ann McKee, an associate professor of neurology and pathology at Boston University who has performed over 50 autopsies on the brains of athletes from age 18 to 83 who played contact sports, has seen evidence of two types of microscopic damage resulting from multiple blows to the head over time. Chronic traumatic encephalopathy, an Alzheimer's-like degenerative disease, strikes the front of the brain, which houses intellect, judgment, learning, and emotions. Affected athletes are in their 30s or 40s before symptoms appear: erratic behavior, staggering gait, amnesia, depression. McKee found a significant indicator of CTE—the buildup of a cell-killing protein called tau—in the brains and spinal cords of deceased athletes and now hopes to identify CTE in the living. Last August, McKee and her colleagues discovered a motor neuron disease similar to amyotrophic lateral sclerosis in three out of 12 deceased athletes, the first evidence that repeated blows to the head might also affect voluntary muscle movements.
How much do parents of athletes need to worry? Researchers at Purdue University outfitted the helmets of 21 high school football players with sensors and found that kids were taking as many as 1,600 hits to the head in a season, registering in many cases some 100 Gs of force (a roller coaster experience equals about 5 Gs). To their surprise, four students who had never actually had a concussion but had taken comparatively more and milder blows to the front and top of their heads showed more cognitive impairment than concussed teammates who took heavy hits mostly to the side of the helmet.
Military wisdom on the topic may soon make it easier to diagnose mild traumatic brain injuries before symptoms appear. About 320,000 troops in Iraq and Afghanistan have suffered concussions from the shock waves generated by roadside bombs and rocket-propelled grenades. So the U.S. Army teamed up with Florida-based Banyan Biomarkers and developed a blood test that accurately diagnosed brain trauma in 34 people with a mild concussion. The test looks for two proteins that enter the bloodstream when the brain is injured. Researchers plan to try it next on 1,200 patients. In addition, the Department of Defense began using eye-tracking goggles last year to measure how well an injured soldier is able to pay attention, the primary cognitive function impaired after a concussion. Someone wearing the goggles watches a circling dot for 30 seconds; ability to focus while tracking the target is measured, and a score is generated to quantify the severity of an injury.
There is optimism, too, about the severe brain traumas that cause a form of coma called persistent vegetative state, in which a person is awake but not aware. Only 3 to 7 percent of people in this state typically recover. But new tactics to jump-start these patients' brains are showing promise as part of the "emerging consciousness" program at the Department of Veterans Affairs. The focus is on combining nursing and rehabilitation services, an individualized therapy program, intensive case management, and psychological support services and education for families and caregivers—a regimen that goes beyond standard care. The program also relies on new approaches such as the use of stimulant drugs like Ritalin, bromocriptine, and modafinil, which appear to galvanize the brain. The VA reports that its multi-pronged program has brought nearly 70 percent of patients back to consciousness.