http://en.wikipedia.org/wiki/Chinese_water_torture
Chinese water torture is the popular name for a method of water
torture in which water is slowly dripped onto a person's forehead,
driving the victim insane. This form of torture was first described
under a different name by Hippolytus de Marsiliis in Italy in the
16th century. Supposedly the torture in dripping water is the slow
rate at which the water flows. The victim can almost predict when
the next drop will fall and a sense of tension builds up. When the
drop finally does fall, a sense of shock and relief follows, only
to be replaced with more tension about the next drop. The release
of tension (no matter how small it is) prevents the victim from
withdrawing inside himself. As this does not require interaction on
the part of the torturer it can be done continuously.
The American television program MythBusters had mixed success with
the Chinese Water Torture myth. They proved that when the victim is
restrained, Chinese Water Torture is in fact torture, but this is
caused by the restraints. The required torture equipment (and
involuntary restrictions on movement) is highly efficient even
without adding the discomfort of the water drip. The water drip
itself, without the equipment, is almost negligible. The show
performed two experiments, one in which a victim was restrained and
had water dripping on her head and another where the victim was not
restrained but still had water dripping on his head. The restrained
victim reported elevated levels of stress and anxiety, while the
unrestrained victim reported a mild level of annoyance. MythBusters
cast member Kari Byron was unable to handle being restrained while
subjected to the Chinese Water Torture for more than a couple of
hours before breaking down.
http://en.wikipedia.org/wiki/Chinese_water_torture
