An integrated circuit for stepwise or continuous microdrive advancement

A circuit for inexpensive automation of a hydraulic microdrive is described. The circuit uses two integrated timing circuits with output periods defined by resistance-capacitance circuits. The output of this circuit operates a relay that controls a small electric motor that runs the microdrive. This system can operate in either a continuous mode for long-term infusion of solutions or in a stepwise fashion for lowering electrodes. When attached to an appropriate microdrive, the circuit can be employed in experiments in which brain-behavior relationships are investigated within anatomical, pharmacological, or electrophysiological paradigms.