Still, there are large numbers of fighters who have never suffered any noticeable brain damage, and doctors have yet to pinpoint why these athletes don't seem to be affected by repeated blows to the head.
"We don't know why two individuals both exposed to the same number of blows and years of fighting, why one person develops chronic brain disorders and one doesn't," Bernick said. "When it comes to cumulative head trauma there are many, many things we just don't know."
During their first visit to the clinic, fighters are given an MRI and a series of cognitive and memory tests. They are tested for judgment and reasoning, and doctors look for signs of impulsiveness and depression. The tests will be used as a baseline for annual checks, and researchers will study all the data to see if there are common links.
"We would hope it would go on forever, but we need at least four years," Bernick said. "We hope to learn enough by then to give us some insight into what happens in real time to individuals involved in activities where they are exposed to head trauma."
Bernick said the study may provide valuable information that can be used in other sports, like football, where concussions are an ongoing issue. The Cleveland Clinic is also involved in concussion studies, including one which looks into the effectiveness of a blood test in identifying concussions in college football players.
Promoter Bob Arum said he welcomes the study, which, he said, could be particularly useful when a boxer is deciding how long he will fight.
"A lot of questions people have about when is enough enough will be able to be somewhat solved by what's being done there," Arum said. "We'll have a body of facts and evidence that we never had before."
Magdaleno, who has been fighting since the age of 8 and has had 132 amateur and 21 professional fights, went with his brother, Jesse, also a professional fighter, for his first test at the clinic. He plans to take the battery of tests after his upcoming March 23 fight against Miguel Beltran Jr. in Tucson, Ariz.
"When I first heard about it I wasn't too interested because I didn't understand it all," he said. "But after it was explained to me, I'm all for it. I want to be an inspiration to others and make them come in and do their tests, too."
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