Michael Bisping was KOed two months into the past after the Dan Henderson KO.

[ianferguson]

I was hit by a drunk driver and knocked unconscious. I woke up in the ambulance, talked to the paramedics and thought I was fine. When the ER doctor asked me my name I opened my mouth to say it and nothing came out. It was unnerving to say the least. The doctor just chuckled and said it would all come back soon. He was right and by his next rounds I was back to normal.

The brain reacts to trauma in strange ways.