Theres this woman that i saw sitting infront of my school, she sits there and shakes her head very fast in a no movement. She stops for a second while staring at people and goes back to doing it. Me and a mate tried to see what was going on but she looked at us for about half a second and did it again.
My other friends saw her walking around while shaking her head and moving somewhere else. At one point apparently she was laughing while doing it.