Constant-current, biphasic titrating stimulator for brain self-stimulation

The design of an inexpensive electrical stimulator is described that produces constant-current, biphasic pulse trains suitable for brain self-stimulation research. This can be programmed to increase or decrease the current amplitude in equal steps. This current titration apparatus was developed to measure changes in the reinforcement threshold for brain self-stimulation after experimental manipulations such as drug administration. It is constructed of integrated circuit (IC) chips, and is interfaced with a minicomputer providing for on line data collection and storage.