Bangerz! Billy Ray Cyrus brought his daughter Miley Cyrus on a dirt bike when she was just 2 years old — and the excursion left her with a “head injury” she’s monitored for years.The “Midnight Sky” singer, 27, shared during the Wednesday, September 2, episode of the “Joe Rogan Experience” podcast that she likes to take SPECT scans of her brain because she “had a head injury when I was, you know, 2 years old.”Miley explained, “It’s bad.