A researcher using cutting-edge imaging techniques has offered further proof that the brain isn't done healing from a concussion once symptoms disappear.

In a study published in the journal Neurology, Andrew Mayer of the Mind Research Network and University of New Mexico compared 50 healthy subjects to 50 people who suffered concussions. His results showed that gray matter abnormalities persisted in those with concussions even four months after the injury.

Although the diffusion tensor imaging scans showed that the brain had not fully healed, other symptoms—such as memory problems, headaches, and depression—had subsided significantly. Diffusion tensor imaging has been used for several years but has recently evolved rapidly. It allows researchers to peer inside the brain and determine space based on the flow of fluids, similar to watching water swish around the edges of a glass. 

Mayer told Healthline that he chose the four-month benchmark because most people who suffer concussions report feeling better after three months. He warned that a brain injury is similar to a sprained muscle.

“Even though someone feels 100 percent recovered, that may not be the case," he said. "When you experience both of those injuries acutely, that's when you have the most pain and the most symptoms. Those symptoms tend to go away before the tissue is done healing.” 

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Sports-Related Head Injuries Getting Attention

In recent months, the U.S. has been involved in a national conversation on concussions. Over 4,500 retired National Football League (NFL) players, who suffered numerous blows to the head over the course of several years, sued the league after developing dementia and other problems. They claimed that coaches put them back into the game too soon after their injuries. In August, the NFL agreed to pay $765 million for concussion-related compensation, medical exams, and research for retired NFL players and their families, as well as legal fees. 

On Monday, 10 former National Hockey League (NHL) players did the same, filing a lawsuit in federal court claiming that the league did not do enough to protect them from concussions. 

Veterans returning from wars in the Middle East also have contributed to research into the damage caused by blows to the head. “They are surviving injuries that previously would have killed them,” Mayer said.

Meanwhile, parents and advocates for young children have voiced growing concerns about the impact of head injuries on undeveloped brains. A new report by the Institute of Medicine has shown that little is known in this area, and called for heightened vigilance.

Mayer is conducting a similar study with a larger sample and a longer, one-year follow up. Results from that research, involving mixed martial artists, could come as early as next year.

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Neurologist Offers New Guidelines

Dr. Christopher Giza, co-author of the American Academy of Neurology's recently updated, evidence-based concussion guidelines, highlighted the need for concussion education, even among health care providers.

He told Healthline that while most professional sports teams have certified athletic trainers, less than half of high school or youth teams do, making implementation of the guidelines difficult. He echoed the need for heightened awareness of concussions among parents, coaches, and athletes. 

He stressed these top five things to remember about concussions, taken directly from the new guidelines:

  1. Anyone suspected of having a concussion should be removed from play and not returned on the same day. Risk of repeat concussion is greatest within 10 days of a prior concussion.

  2. Most concussions occur playing football. Girls are at greater risk for concussion than boys in sports such as basketball, soccer, baseball, and softball.

  3. There is no single test to diagnose concussion—it is a clinical diagnosis.

  4. There are multiple diagnostic tools to help diagnose concussion, including computerized tests, balance tests, standardized symptom checklists, and reaction time tests. These should be used in conjunction with a medical history, physical exam, and a neurological examination by an experienced clinician.

  5. There is no rating scale for concussions. Concussions require individualized management.