Inside Stanford University's Arrillaga Athletic Center, Dr. Jamshid Ghajar, director of the Concussion and Brain Performance Center at Stanford, strode past athletes who were receiving individual guidance and basketball players who were perfecting free throws. Ghajar has spent decades researching concussions and the implications for student athletes, but even as he sat down for an interview in an adjacent office, the traumatic brain-injury expert said candidly, "The real fact is that we don't know what a concussion is."
Every year, around 3.8 million concussions are reported, according to the Brain Trauma Foundation, which was founded by Ghajar in 1986. And yet mystery and misconception shroud concussions, leading many doctors to prescribe inadequate treatment that in some cases goes against what Ghajar prescribes: sleep and exercise.
Ghajar, who has pioneered both a way to diagnose and treat concussions, explained that it used to be that when a person passed out due to a hit to the head, it was called a concussion. This term, however, does not indicate the severity of the injury. Today, the diagnosis of a concussion is made based on the patient's history, an examination and occasionally imaging -- even though, Ghajar notes, 90 percent of CT scans and MRIs are normal in people with concussions.
Scott Anderson, director of athletic training at Stanford, works with Dr. Ghajar and points out that there's a perception that a concussion results in identifiable damage of the brain -- a visible, focal dent, as if the brain has been bounced on the ground like a basketball. The reality is quite different.
"What we're talking about is brain performance. We're talking about how your engine runs, not what your engine looks like," Anderson said.
Ghajar has focused on identifying the symptoms of a concussion.
"If you look at all the literature, what seems to pop up is the main things that people have problems with, and it turns out to be attention and balance. ... Your sensory motor function is intact, but you can't somehow integrate it with the outside world," he said.
Ghajar pointed out that attention involves keeping up with the outside world and predicting information so that one can process it just in time. He used the example of driving a car, wanting to make a left turn and having to predict both where another car is going to be and where you're going to be in relation to it. This ability to predict information is impaired when people have a concussion.
According to Ghajar, the reason for this impairment is because 99.9 percent of head injuries are in the front of the brain.
"You become cranky, you become irritable, your emotions become very labile. You cry easily, you laugh easily, you can't sleep. All sorts of problems occur from that whipping around in the front part of the brain," Ghajar said, adding that if the force from a head injury affects the inner ear, people can experience a loss of balance.
These observations led Ghajar to think of a way to efficiently test prediction. He turned to eye tracking because the eye, he explained, visibly communicates one's attention.
"Your eye looks where you want to pay attention to, so if you really want to figure out how well somebody predicts you (show) them a dog going around in a circle at a known speed and (their) brain goes 'Oh, it's going around at this speed. I know where and when it's going to be,' and (their) eye is going to land on it," Ghajar said.
Eight years ago, the Brain Trauma Foundation's eye-tracking test caught the attention of the United States Department of Defense, which was interested in putting the eye-tracking test into goggles. Since then, the military has invested $30 million into eye-tracking technology and clinical trials, a portion of which are conducted in Palo Alto schools through a program called EYE-TRAC Advance.
The 30-second test is simple and requires a person to track a dot as it moves in a circle. The graph of data for a person with no concussion shows a cluster of points around a central point. The graphs for people with concussions show data points that are scattered, a testament of their difficulty tracking the dot.
"(Eye tracking) shows you what the brain is doing in real time," Ghajar said.
One reason people aren't able to track that dot is sleep deprivation, a condition that is pronounced in people with concussions. Ghajar explained that, for unknown reasons, people who have a concussion immediately experience sleep problems.
"They wake up frequently during the night; they wake up in the morning, (and) they feel fatigue. Then, they start taking naps during the day, and then they really don't sleep well at night, and then the whole thing gets messed up," he said.
His simple prescription for curing concussions by increasing sleep and exercise goes against the common practice of prescribing inactivity to people with concussions. He explained that, while it's important that a person with a concussion not be hit in the head again, the injury should not prevent the person from exercising.
"There's something about cardio exercise that retrains the brain," Ghajar said. "Everybody knows it prevents dementia; it enhances focus. They do know there's more neurogenesis. It enhances brain cells when you exercise.
"We should be emphasizing it as a therapy but also prophylactically, along with good sleep," he said.
The good news is that people with concussions can and do improve with increased exercise and sleep. Ghajar noted that even patients with symptoms of concussion for multiple years can make a full recovery with exercise and sleep.