Quantitative relations between avoidance behavior and pituitary-adrenal cortical activity.

Scientists trained monkeys to press a lever to avoid electric shocks. They measured how often the monkeys pressed and how many shocks still got through. At the same time they drew blood to check steroid levels from the adrenal gland.

The goal was to see if the animal’s own behavior and the shocks it did receive changed stress-hormone output.

Both the lever-pressing rate and the number of shocks that slipped through helped predict the hormone numbers. High response rates or many shocks both pushed steroid levels up.

No single factor told the whole story; the two pieces of data worked together.

Wilkie (1973) later showed that steady, predictable shock periods first speed responding and then slow it, adding a time dimension to the 1962 rate-hormone link. The two studies mesh: schedule timing shifts rate, and rate feeds back on stress chemistry.

DeWeese (2009) found heart rate and blood pressure rise and fall with each response burst inside fixed-interval cycles. The 1962 steroid data and 2009 cardiovascular data sit side-by-side, showing one behavior streams into several body systems at once.

Mosk et al. (1984) revealed that stronger shocks do not always produce better avoidance once a minimum intensity is passed. That finding narrows the 1962 result: shock frequency matters for hormones, but extra intensity does not help after the needed floor is met.

Catania et al. (1974) showed pigeons slow their pecking when the response-shock window widens. Their rate curve and the 1962 hormone curve move together, tying slower responding to both fewer shocks and lower stress chemistry.

When you run avoidance or escape programs, remember the client’s body is listening. Each press and each aversive event that still happens can nudge autonomic arousal. Track both behavior counts and aversive contacts; if either climbs, check for hidden stress effects. Use the least intrusive schedule that keeps the client safe, because more shocks or harder effort can both stir physical stress.