Stimulus generalization as a function of the delay between training and testing procedures: a reevaluation.

Schroeder et al. (1969) worked with pigeons to see what happens to stimulus generalization after a long break.

Birds first learned to peck a colored key for food. The next day some birds started the test right away. Others got a quick three-minute warm-up first.

After 24 hours the generalization curve looked flat. The birds responded almost the same way to every color.

A short warm-up with the original color brought the steep peak back. The curve looked just like it did on day one.

Stevenson (1966) showed that spacing test colors close together also flattens the curve. R et al. now show that time alone can do the same thing.

Northup et al. (1991) later kept pigeons accurate after 24 hours in a memory task. Their trick was extra training with a distractor key. Both studies say the same thing: a small prompt keeps old learning alive.

Harris et al. (1978) saw a U-shaped memory curve in conditioned suppression. R et al. found a similar dip and recovery in stimulus control. The shape differs, but the message matches: behavior weakens then bounces back with the right cue.

If you test a client after a weekend, the skill may look gone. Run a quick warm-up with the original stimulus first. Five reinforced trials can restore the sharp discrimination you saw on Friday. Use this before probe sessions, toilet-training checks, or any task that sat idle for a day.