With school back in session, school sports are *also* back in session.

So, we invited Dr. Ian Smith back to our show to address a viewer's concussion concerns.

Question: "I have two children. One plays soccer and one plays field hockey. I'm very concerned; If they should get hit in the head and they don't show any symptoms, should I still be concerned? And if they do have a concussion, how long do I have to keep them out of daily activities or their sports?"

— Nicole, viewer

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Answer: Since no two children are alike, Dr. Ian advises that no matter what, you should always check with a healthcare professional if your child hits their head.

But what exactly is a concussion? According to the doc, it's a contusion or a bruise on your brain.

"When you hit your head," Dr. Ian says, "the brain goes back and forth, and it's the back and forth movement that becomes a problem." He continues, "You can stretch or tear some of your neurological cells and that can be very problematic."

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Sometimes a concussion can have no symptoms whatsoever, says the doctor, so if a child has hit their head, it doesn't mean they're always fine. But, he says, there are some symptoms you should look for.

CONCUSSION SYMPTOMS (according to Dr. Ian)

• Headache
• Mild cognitive impairment
• Mild dilation of pupils
• Lack of coordination

He adds that all children are different, so the symptoms can be different. If you're wondering if your child should go back to sports, he names the American Academy of Pediatrics as a good place to consult.

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