A new gustometer for testing taste discrimination in the monkey

A fully automated, 10-channel gustometer for use with nonhuman primates is described. The system, constructed primarily from commercially available components, includes an intelligence panel (containing sample spout, reward spout, and two operant response keys) that attaches to the door of a standard primate cage. The novel feature of the gustometer is a sample delivery spout that can be flushed, rinsed, and refilled within a specially designed rinsing chamber. All wetted surfaces of the gustometer are either Teflon, glass, or stainless steel. Flame photometric analysis confirmed the absence of cross-contamination between trials. Behavioral data collected from one rhesus monkey using a shock-suppression procedure demonstrates the detection threshold for sodium chloride. Improvements to the design, including the addition of pressurized sample delivery triggered by a lickometer circuit, are discussed.