An apparatus for delivering pain shock to monkevs.

HEFFERLINE et al. (1963) built a metal box that holds only a monkey’s tail.

The tail sticks out through a small hole. Wires clipped to the tail deliver brief electric shocks.

The rest of the monkey stays free inside a cage, so sessions can run for hours without re-wrapping tape or straps.

The paper shows drawings and parts lists. It does not report any behavior results.

The goal was simply to share a gadget that keeps shock delivery steady.

Jones et al. (1977) later used the same tail-shock rig. They showed shock can make a squirrel monkey drink, not just freeze or bite.

Lyon et al. (1970) paired a tone with that shock and taught monkeys to show aggressive posture on cue. The 1963 hardware made both studies possible.

Azrin et al. (1967) built a rat version with floor electrodes. Both papers swap species but share the same spirit: build cleaner, kinder ways to give aversive stimuli in the lab.

You will never use tail shock in clinical ABA. Still, the paper is a snapshot of how early behavior analysts thought about precise stimulus control.

When you read later monkey studies, check the methods. If you see “tail electrode,” chances are the 1963 box is under the lab bench, still doing its job.