Observing behavior in squirrel monkeys under a multiple schedule of reinforcement availability.

De Lorge et al. (1971) worked with squirrel monkeys in a lab cage.

A light or tone told the monkey if food was available or not.

The team changed how often the food cue came on and watched how much the animals looked at the signals.

Monkeys looked less when food cues were rare.

A quick flash of the no-food cue brought looking back for a moment.

Looking tracked the chance of seeing food news, not food itself.

Bailey et al. (2008) ran a similar test with pigeons. They saw the same drop in looking when the birds no longer had to peek to see the cue. The two studies line up: less work to see the cue means less looking.

Hilton et al. (2010) moved the idea to humans. They used a multiple schedule to calm high-rate social approaches in an adult with ID. The schedule worked just like it did with monkeys: the person slowed down when the lanyard signaled no attention.

Schlundt et al. (1999) showed that people only pick the richer schedule when cues for each side are in view. Together these papers say: cues control behavior across species, but only if the learner can easily see or hear them.

Your client may keep scanning the room because the room gives news about reinforcers. Put the cue where they can see it without extra work. Make the cue brief and tied to the reinforcer. When you want to thin the schedule, first lengthen the no-reinforcer cue slowly, just like Hilton et al. (2010) did with the lanyard. This keeps stimulus control tight while you reduce reinforcement density.