Free-operant avoidance in the pigeon using a treadle response.

Researchers taught pigeons to avoid mild shock by stepping on a small treadle.

The birds could press any time; each press postponed the next shock.

No lights or tones told them when shock was due—pure free-operant avoidance.

The pigeons learned the foot-press in one session and kept pressing steadily.

Their response pattern was more stable than rats doing the same task.

The treadle let the birds move naturally, so the behavior looked smooth and stereotyped.

Hineline et al. (1969) first showed pigeons avoiding shock by key-pecking. The 1970 study swaps the key for a treadle and sees faster, cleaner performance—an upgrade, not a clash.

Johnston et al. (1972) kept the treadle and varied shock timing and strength. They found shorter intervals and moderate shock push rates even higher, building directly on the 1970 baseline.

Edwards et al. (1970) ran the same schedule but kept the old key-peck. Their birds acted differently when warning signals were added, showing the response form you pick can change what you measure.

If you study or teach avoidance, choose a response the animal can do comfortably. For pigeons, a treadle beats a key. The same idea applies to humans: pick an escape response that feels natural—maybe squeezing a stress ball instead of pressing a tiny switch. Faster acquisition, cleaner data, happier clients.