Multiple operant discrimination training to increase the precision of stimulus deltas following treatment of challenging behavior

Lambert et al. (2021) worked with one child with autism who used an AAC device.

The team first used FCT to replace the child’s problem behavior with a mand.

Next they added short discrimination trials. In these trials only some reinforcers were available. The goal was to teach the child to ask only for what he could actually get.

The extra discrimination training worked. The child started to mand only for items that were in sight and available.

Problem behavior stayed low while accurate mands stayed high.

Matter et al. (2017) showed that FCT alone can cut problem behavior. Lambert goes one step further by adding a quick discrimination phase after FCT.

Hansen et al. (1989) taught adults with ID to do conditional matching by training all parts at once. Lambert uses the same idea: teach the child to watch both the item and the adult’s cue before manding.

Catania (1973) found that pigeons learned best when redundant cues were faded to single cues. Lambert mirrors this by first giving rich cues (item in view, therapist present) then thinning them to natural levels.

You can copy this in any clinic or classroom. After FCT is stable, run five-minute sessions where only half the usual items are in reach. Reinforce correct mands and withhold reinforcement for impossible ones. Within a week most kids will stop asking for absent items and problem behavior stays low.