Electronic drinkometer and recorder.

The author built a small circuit that counts every time a rat licks a water tube. A metal spout sits in the cage. Each tongue touch closes the circuit for a split second.

The circuit sends pulses to a micro-ammeter and to a pen that marks a paper roll. The paper lets you see lick rate second-by-second. A switch filters out quick double-counts so the record is clean.

This is a hardware recipe paper. No data, no graphs, no stats. The author only shows the wiring diagram and a photo of the finished box.

The paper ends with a parts list and a price tag that would make a 1961 lab manager smile: a few dollars for tubes, resistors, and a relay.

Gurley (2019) makes the drinkometer look like a museum piece. That team gives you a full Raspberry Pi operant chamber for under $200. It still records licks, but also plays lights, tones, and saves data to a thumb drive.

Gilchrist et al. (2018) and Maharaj et al. (2020) keep the automation spirit but swap the sensor. They use cheap accelerometers or a Kinect to count hand flaps and body rocks instead of tongue touches. No soldering required.

Ellement et al. (2021) use EMG to catch silent teeth grinding. Like the 1961 box, the tool plugs straight into an FA workflow, but the target is bruxism, not licking.

If you run a rodent lab and only need lick rate, the 1961 circuit still works. For every other use case, grab the open-source upgrades. Build Gurley’s Pi chamber for full stimulus control, strap on Gilchrist’s accelerometer for stereotypy, or plug in Ellement’s EMG for bruxism. The core idea—let the machine count while you watch something else—has not changed in sixty years.