Delayed escape from light by the albino rat.

Keller (1966) worked with albino rats in a small chamber. A bright light stayed on until the rat pressed a lever. The twist: the light did not turn off right away. The team added delays of 0, 2, 4, 8, or 16 seconds between the press and the escape from light.

The researchers wanted to see how these extra seconds changed the speed and pattern of the escape response.

Longer delays made some rats wait longer before pressing. The most common response time stayed the same, but more very slow presses showed up. During the delay, rats also pressed the bar in bursts that looked 'superstitious'—they were not needed to escape the light.

Even a 2-second gap was enough to create these extra, useless presses.

Griesi-Oliveira et al. (2013) later saw the same drop in response speed when the delay was to a conditioned reinforcer, not the light itself. This extends V's finding: the delay rule holds across different kinds of rewards.

SIDMAN (1962) showed rats could avoid shock with only time cues and no warning light. V added an explicit delay after the response, building on that pure-temporal setup.

Mann et al. (1971) moved the same escape-avoidance schedule to human skin-resistance responses and still saw clear stimulus control. The contingency travels across species and response forms.

Hineline et al. (1969) used pigeons and a key peck, gradually shifting from immediate escape to avoidance. Their transfer procedure mirrors V's goal: show how escape behavior changes when the consequence is no longer instant.

If you add even a short pause between a client's response and the reinforcer, you may see slower responding and extra, off-task behavior. Keep reinforcement immediate when teaching new skills. If a delay is unavoidable, watch for superstitious chains and use probe data to check efficiency.