Effects of response-dependent and independent electric shock on schedule-induced polydipsia.

Scientists watched rats drink water while they worked for food.

Some rats got a quick shock no matter what they did. Other rats only got shocked if they pressed the lever.

The team wanted to know which kind of shock would stop the extra drinking.

Shocks that came on a timer cut the rats’ water intake.

Shocks that were tied to the lever press did not.

The drinking was sensitive to how the shock was delivered, not just the shock itself.

Hymowitz (1976) later showed that timed shocks still worked even if they came 1–15 seconds late, and that thinner rats felt the shock less.

Rosenblith (1970) had already proven that second-order food schedules make rats drink like this, so the 1974 team had a solid setup to test shock effects.

Schneider et al. (1967) found that response-contingent shock can either raise or lower lever pressing depending on its link with food, which helps explain why the same contingent shock did not touch drinking in the 1974 study—adjunctive drinking follows different rules.

If you ever use mild aversives or timeouts, remember that contingency matters. A consequence that is not tied to the target behavior may still cut that behavior through general suppression. For clients who engage in adjunctive habits like excessive drinking or pacing, check whether any environmental aversive is truly response-dependent or just happening on a schedule. Shifting it from timed to contingent, or removing it altogether, could spare useful behaviors you want to keep.