Tua Tagovailoa sustained a major hit in a Sept. 25 game that the team called a back injury that raised questions. Now, he's being treated for a possible concussion after a Thursday game.

The latest generation of hard hats are designed to cushion the brain during an impact by absorbing forces that cause the head to spin.

A concussion can make it difficult to converse in a noisy room. Scientists say that's because the injury has impaired the brain's ability to process sounds.