There may be no hotter health topic in sports circles this winter than concussions.

While parents, students, athletes, coaches and doctors have been on this case for some time — with Hollywood on board, the topic will get even hotter.

The movie “Concussion” premieres Christmas Day and stars box-office heavyweight Will Smith, who portrays Nigerian-born forensic pathologist Dr. Bennet Omalu. He’s the physician who discovered a disorder similar to Alzheimer’s while conducting an autopsy on a former NFL player, then went on a crusade to publicize the dangers of football-related head trauma.

Since Omalu’s investigation began more than a decade ago, we have learned a great deal about these unexpected and often violent blows to the head.

Former NFL quarterback Brett Favre spoke to CBS “This Morning” about the memory loss he suffered due to concussions.

“This was a little shocking to me that I couldn’t remember my daughter playing youth soccer,” Favre said.

Favre was sacked 525 times during his 20-year career.

Concussions are responsible for countless lawsuits against professional sports leagues brought by pro athletes in recent years. In 2014, the NFL reached a tentative $765 million settlement over concussion-related brain injuries among its 18,000 retired players.

In 2015, several pro hockey players sued the NHL for what they called “long-term neurological problems stemming from concussions they sustained while playing for the (NHL),” ESPN reported.

But many nonprofessional athletes also suffer concussions — and the uncomfortable and worrying symptoms that can accompany them.

“I was extremely moody after I sustained my third concussion from playing football back in high school. I just wasn’t right,” said a 29-year-old Boston-area man. “That bothered me more than the headaches and extreme sensitivity to light, my other symptoms.”

LifeZette dove into the details of this injury to explain it thoroughly for readers.

What, Exactly, is a Concussion?
Also called a mild traumatic brain injury, this brain injury is usually caused by a blow or jolt to the head. A concussion may also happen when the head and upper body are violently shaken, such as in a car crash, during a sports injury, or even during a seemingly benign fall.

Dr. Chris Giza, a pediatric neurologist and traumatic brain injury researcher at the University of California, Los Angeles, said, “Now we know that 90 percent of concussions occur without a loss of consciousness,” according to CBS News.

“The brain floats in cerebral spinal fluid,” said medical orthopedist Dr. William Heinz of Ortho Associates in Portland, Maine. He’s a specialist in diagnosing and treating sports-related concussions and musculoskeletal injuries. “When the brain shakes or rotates inside the skull and that fluid can’t absorb the blow, a concussion can occur.

“Rotational injuries are particularly worrisome and can have more serious consequences. That’s why blindside hits have been banned in all sports. This is when you are likely to receive a rotational injury,” he said.

What Should You Do About a Concussion?
If you think you or your child has experienced a concussion, get medical help promptly, particularly for severe symptoms, which can include (but aren’t limited to) vomiting, a loss of consciousness longer than 30 seconds, a headache that gets worse over time, and changes in physical coordination. Slurred speech or other changes in speech are also cause for concern.

“Seventy-five percent of all concussions will present headache as a symptom,” Heinz said.

The American Academy of Pediatrics recommends playing it safe and checking with your doctor if your child receives anything more than a light bump on the head. Typically, rest is advised. No medicine can cure a concussion. Cognitive rest is also important, which includes limiting homework, reading, and anything that stimulates cognitive brain activity.

A relatively new field of study is also looking at “second impact syndrome.” This occurs when a second concussion is sustained after a first concussion hasn’t fully healed.

“Second impact is when particularly serious consequences to concussion can occur — even death,” Heinz said.

Today, parents, coaches, players and medical professionals are much more educated about concussions.

“We are stressing to everyone that a concussion is a real injury that needs to be taken care of — mainly by rest, then a gradual return to activity,” Heinz said.

A doctor can help map out a very specific plan to safely return a student to school and to the athletic field.

Todd Nelson, assistant director of the New York State Public High School Association, told LifeZette, “Our state requires participation every two years in a concussion education course for all nurses, coaches, trainers, physical education teachers — anyone who deals with kids and sports. We also have information that parents must receive on concussion before they can register their child for team participation.”

So, should kids stop playing contact sports?

“Football and all sports are great — great for kids — and yes, they have risks,” Nelson said. “It’s our responsibility not to abandon these sports, but to increase and highlight education about concussion, which in turn decreases risk. Life itself has risks, and you can get a concussion slipping on your steps,” he added.

“The most important piece of advice to anyone about concussions is this: When in doubt, sit them out,” Heinz said.

“I’m still glad I played, even though my last concussion ended my career,” the Massachusetts 29-year-old said. “Football is a great, great sport.”

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