After five days they started to complain about the circumstances and events that led them to where they were and started to demonstrate severe paranoia. They stopped talking to each other and began alternately whispering to the microphones and one-way mirrored portholes. Oddly, they all seemed to think they could win the trust of the experimenters by turning over their comrades, the other subjects in captivity with them. At first, the researchers suspected this was an effect of the gas itself...
After nine days, the first of them started screaming. He ran the length of the chamber repeatedly yelling at the top of his lungs for three hours straight, he continued attempting to scream but was only able to produce occasional squeaks. The researchers postulated that he had physically torn his vocal cords. The most surprising thing about this behavior is how the other captives reacted to it... or rather didn't react to it. They continued whispering to the microphones until the second of the captives started to scream. The two non-screaming captives took the books apart, smeared page after page with their own feces and pasted them calmly over the glass portholes. The screaming promptly stopped.