I took a tour of the old Missouri state penitentiary at night about 2 years ago. We got to the area of the jail where they kept really troubled people underground in pitch black where they were left to die with bare minimum food every so often. We (the tour group) were put into one of the sells and had the lights turned off to see how it felt to be in there. I was in the back corner of the cell and my right elbow was pinched. As the pinch backed away my jacket was pulled to the back corner. After the lights came on there was I turned around and there was no space for person to have that. I talked to the tour guide after and he said that people actually complian about being pinched the lights go out.
TL:DR something pinched me in pitch black solitary confinement.