Where to Watch Vile (2011)

Give Till It Hurts.

A group of people awaken to find themselves prisoners in a mysterious house with no means of escape. They are each outfitted with electronic devices attached to the base of their skulls. The chemicals that the brain produces when in pain are collected by the devices, and when it collects a predetermined amount, the doors will be opened. In order to escape, they must hurt themselves and each other.