Some observations on the adventitious reinforcement of drinking under food reinforcement.

Rats earned food on a variable-interval schedule. The feeder clicked every so often, no matter what the rat was doing.

A water spout sat in the corner. The team watched to see if the animals would drink even though water was never required for the food.

Drinking showed up right after food pellets dropped. The closer the water tube, the more licks the rats made.

Shorter gaps between pellets also bumped up the sipping. The water had no food value, yet the timing made drinking stick.

Falk (1966) ran the same VI food set-up and saw the same polydipsia, a clean direct replication.

Cohen (1975) went further, showing the induced water itself became a reinforcer. Food rate changed how much the rats "wanted" the plain water.

Paul et al. (1987) flipped the script: they punished the extra drinking by delaying the next pellet. Drinking dropped when licks cost time, proving the behavior is operant, not reflex.

Morris et al. (1982) tested the old idea that food cues trigger the drinking. Five experiments ruled that out, pointing to competition among behaviors instead.

Your client might pick up odd habits while waiting for reinforcement. If delivery is clock-like, watch for extra rocking, tapping, or even sipping from a cup that is always there. Move reinforcers around, add brief pauses, or vary the place of edible rewards so accidental chains don’t take root.