Research in a laboratory required a sensitive, reliable, inexpensive touch detector for use with rats to test the reinforcement of inhibition. A small touch detector was also desirable so that the detector could be mounted on the rat's cage close to the object being touched by the rat, whose touches in turn were being detected by current passing through the animal, thereby reducing the influence of other signals. A detector was desired that would detect several hundred M[Ohms], and directly operate a multipole relay. Earlier attempts to develop such a detector used seven transistors, but those units became unreliable due to transistor failure. It seemed desirable to minimize the number of components. In this article, the author talks about a sensitive, reliable, and inexpensive touch detector that can be used in testing the reinforcement of inhibition. (Contains 2 figures.)