Acquisition of stimulus control while introducing new stimuli in fading.
Drop quick probe trials while you fade prompts so the target stimulus grabs control faster.
01Research in Context
What this study did
Wetherington (1979) taught adults to pick the correct line tilt.
The trainer first showed a dark line plus extra bright cues.
He then slowly dimmed the extra cues while slipping in quick test flashes.
These flashes were probe trials that checked if the line alone now controlled the choice.
What they found
The line became the only cue that mattered.
Probe trials sprinkled through fading made the switch happen faster.
No probes meant slower, shakier stimulus control.
How this fits with other research
Christophersen et al. (1972) already showed plain fading beats no fading when kids learn to read pictures.
Wetherington (1979) adds one simple twist: drop probe trials into the fade.
Borgen et al. (2017) later moved the same fade logic into a classroom.
They stacked easy instructions before hard ones for autistic preschoolers and compliance jumped.
The lab trick of fading plus probes now works for social skills too.
Why it matters
If you fade prompts without checking, you may think the new stimulus is in charge when it is not.
Slide in quick probe trials as you thin the prompt.
One flash of the target cue tells you right away if the learner is following the right stimulus.
Use this in any program where you shift from prompts to the natural cue: matching letters, identifying emotions, or following written directions.
Want CEUs on This Topic?
The ABA Clubhouse has 60+ free CEUs — live every Wednesday. Ethics, supervision & clinical topics.
Join Free →During your next prompt fade, insert one probe trial every five trials and record if the learner still responds correctly to the target cue alone.
02At a glance
03Original abstract
After establishing discrimination between a red positive stimulus and a green negative stimulus, the lowest intensity colors that restricted all responding to the positive stimulus were determined. Then, two new white lines differing in terms of line orientation were each superimposed on one of the colors and were increased in intensity. Thereafter, the intensity of the colors was decreased and eventually eliminated. Probe stimuli consisting of the lines presented against dark backgrounds were presented before each change of stimulus intensity, and probe responding was used to assess the control acquired by various dimension of the new stimuli during the course of fading. The lines acquired control of responding while they were being introduced, and control was strengthened as the colors were attenuated. Such a locus of acquisition was attributed to the starting intensity of the original controlling stimuli and was explained in terms of stimulus blocking. Finally, using probes while introducing the new stimuli enhanced the acquisition of control by the new stimuli.
Journal of the experimental analysis of behavior, 1979 · doi:10.1901/jeab.1979.32-121