ANN ARBOR, Mich. – Kallie Woodward was a mess. The 19-year-old Division I field hockey player was diagnosed with a concussion in early 2013 and it wasn't the first time she suffered a hit to the head during play. Her symptoms were beyond concerning.

View photos The BNA test involves wearing a hairnet with 256 electrodes. (Yahoo Sports) More

"She had headaches, sleep problems, attention and memory issues," said Jeffrey Kutcher, a neurologist at the University of Michigan who treats college athletes all over the country. "Her mood was down. She was not herself. She was usually very outgoing, but she appeared depressed. It was a significant constellation of stuff."

Woodward (whose name has been changed to protect her privacy) was put through a test that involved wearing a hairnet with 256 electrodes. The net was soaked in a combination of electrolytes and baby shampoo and placed on her head. (One lab technician said the hairnet feels like "an octopus giving your head a hug.") Then she was asked to respond to a series of computer beeps by pressing a button.

The results may have saved her playing career. And this slimy hairnet may do the same for athletes at all level of sports, all the way up to the NFL.

"Potentially," Kutcher said, "it could revolutionize everything."

A revolution is needed. Head trauma and its effects are one of the scariest subjects of our era, and not a lot is known about what's going on in the brain when a head injury happens. Chronic traumatic encephalopathy (CTE), the neurological disease that is often found in athletes who suffer from repetitive brain trauma, can be diagnosed only after death. That has created frustration and fear for those who can't know if their symptoms are related to in-game hits or something else altogether. In Woodward's case, it was difficult to know when she could be cleared to return to the field – or if she should be cleared to return at all.

"How much of her symptoms are from the concussion," wondered Kutcher, "and how much are from post-concussion syndrome?"

The test he gave to Woodward – which has just been approved by the FDA – would help lead to an answer. Developed by an eight-year-old Israeli company called ElMindA, it is known as the "BNA test" (short for "Brain Networks Activation"). It is designed to show how the brain's networks are responding – essentially providing a heat map of the mind.

"This is to a concussion," Kutcher explained, "what the MRI is to an ACL."

The initial test provides the baseline for brain activity. Then, after a concussion or other head injury, an athlete can take the test again and the "before" and "after" maps can be compared.

In Woodward's case, the maps showed steadily improving brain function over several weeks, even though her symptoms persisted. Kutcher, seeing the BNA map change, cleared her to go back onto the field.

View photos A networked brain showing the BNA network progress. (Courtesy of ElMindA) More

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