Which of the following lines could be considered the main idea of “Head Games”?

Which of the following lines could be considered the main idea of “Head Games”? It’s important to take things slowly because people who’ve had one concussion are at much higher risk of a repeat.
Recovery depends in part on previous concussions.
Other conditions, like an anxiety disorder, depression, migraines, or attention deficient hyperactivity disorder, can also extend the recovery time.
That means no cell phones, computer games, television, or even books for a few days.