When my teenage daughter came off the soccer field at the end of a game complaining of a headache, I brushed it off — even when she mentioned another player had hit her in the head during a scuffle for the ball. The blow had been mild enough not to disrupt play, so I gave her ibuprophen and encouraged her to rest. When the headache persisted, I chalked it up to migraine tendencies.

Imagine my grief and guilt when four days later the school athletic trainer diagnosed her with a concussion. I couldn’t understand how I had missed the signs.

I’m not the first mom to be shocked by a child’s concussion. Due to the myriad myths surrounding this condition, it often takes parents by surprise.

In fact, earlier this year the Congress of Neurological Surgeons (CNS) revealed that concussion remains the most underreported and underdiagnosed head injury.

To help you avoid mistaking or mistreating your child’s condition, should he suffer a bump to the head, I’ve unmasked six common concussion myths:

Myth: You can tell right away when someone has a concussion. They’ll vomit and have a bad headache.

Fact: Symptoms can take hours or even days to appear. And because each brain is different, reactions to the injury vary from child to child. 

Here are 11 common symptoms of concussion:

  • Dazed look
  • Disorientation or confusion
  • Decreased balance, coordination or reaction time
  • Memory loss
  • Nausea and or/ vomiting
  • Slurred speech
  • Dizziness
  • Blurry or double vision
  • Headache
  • Sleep problems (too much or too little sleep)
  • Sensitivity to light or sound

This list is not exhaustive. Check out the CDC’s Heads Up to Parents site for more information.

Symptoms also differ between boys and girls. A 2011 study in the Journal of Athletic Training found that both boys and girls report headaches after a concussion. But boys more often experience amnesia and confusion or disorientation, while girls may describe themselves as being drowsy or sensitive to noise.

Myth: You have to be knocked unconscious for it to be a concussion.

Fact: According to the CNS, only about 10 percent of concussion-inducing blows cause the person to black out. And a concussion can occur even without a direct blow to the head.

An impact to another part of the body, such as a hard fall, can sometimes jar the head enough to cause the brain to come in contact with the skull’s interior. It is this internal collision that causes the injury.

Myth: Don’t let a concussed person fall asleep.

Fact: We’ve long heard that you should rouse a person every few hours after they’ve experienced a hit to the head to prevent a coma. In reality, after suffering a concussion your child can (and should) be allowed to sleep. His brain requires rest to begin healing.

However, it is a good idea to keep an eye on your child for the first day or two to watch for the appearance of new behaviors and symptoms, or a decrease in functioning that could require an emergency room visit.

Myth: A concussion is “no big deal.” Kids should just shake it off.

Fact: A concussion is also known as a mild traumatic brain injury.

Not only is it unwise for your child to continue in sports-related activities while recovering from a concussion, she may also need to cut back on mental stimulation.

Among the Center for Disease Control’s (CDC) recommendations for concussion patients are that they:

Get plenty of sleep at night, and rest during the day.

Avoid physically demanding activities (e.g., sports or working out) or those requiring much concentration (e.g., sustained computer use, reading).

The CDC suggests kids not return to activities until they can engage in them without symptoms returning and to slowly increase the level of activity. For some kids it may mean a reduction in school hours, homework amounts, or both.

The American Association of Pediatrics offers online a helpful form your pediatrician can complete to direct the school on accommodations to be made should your child have a concussion. 

Myth: Only football and hockey players sustain concussions.

Fact: According to the American Academy of Neurology (AAN), football and rugby top the list of sports where boys are most susceptible to concussion, followed by hockey and soccer.

Girls face the greatest risk of concussion while playing soccer and basketball.

For younger children (birth to 9 years), bicycling and playground activities account for the greatest number of head injuries, including concussions.

Myth: As long as my child wears a helmet, he won’t get a concussion.

Fact: Helmets prevent skull fractures, not concussions.

While a padded helmet or other protective device may reduce the impact to your child’s cranium, none of them can stop the forces of motion that cause internal brain impact. Parents are encouraged to make sure their child’s helmet fits well and is kept in good condition to reduce the risk of concussion.

With a better understanding of concussions, you can be more aware of what you’re seeing (and what to do) if one happens to your child or another child in your care. Because concussion is more than just a headache — for you and your child.

Lara Krupicka is a parenting journalist and mom to three girls, two of whom have suffered concussions.