Ok, I will do my best to describe. I have a little OEG bantam named E-bay that my absolute favorite. She is the sweetest, tamest, talkative little chicken I have ever owned. So this morning as I am in the coop feeding and watering and I hear this noise coming from above me. I look up and E-bay is in her favorite roosting spot on top of a cabinet and she is moving her head from side to side and the back of her head is touching her back. The noise I was hearing was her beak hitting the roof!, so you can get the picture of what it is she is doing. I can tell that this movement is completely involuntary. I thought she was in the middle of the death roll so I picked her up and she stopped. By the way this 46 year old man was near tears. she is approx 3 years old. I set her on the ground and she immediately went after the morning treat of black oil sunflower seeds they get and then she started it again and of course another hen attacked her when she did this. I picker her up and she stopped. I place her in a dog crate as I had to get to work. Anyone have a clue what is causing this or what she might have. I have never seen it before in my 40 years being around chickens.