RBT guideCore RBT Concepts
RBT Discrimination Training: SD versus S-Delta
Discrimination training teaches responding to the correct cue (SD) and not to others (S-delta). Reinforcement is available for the target response only in the presence of the SD.
Short answer
Discrimination training establishes stimulus control: the target response is reinforced in the presence of the discriminative stimulus (SD) and not in the presence of other stimuli (S-delta). The SD does not make the behavior happen by magic. It signals that reinforcement is currently available for that response. Implement the cues, prompts, and consequences the plan names.
The cue that means reinforcement is available
Discrimination training teaches responding to the correct cue and not to others. The SD signals that reinforcement is available for a specific response. Identify the controlling cue before you decide the response was ‘close enough’. Acquisition lists this as a Domain C skill. Generalization is the later job of transferring that control. Do not skip discrimination and hope generalization appears.
If “touch red” is the SD, touching red is reinforced. Touching green is not (S-delta), even if touching is the same motor pattern.
An SD is not a prompt. A prompt is extra help. The colored card can be the SD; a finger point can be a prompt to be faded. See prompting.
How DTT usually runs it
Many programs use discrete trials: present the SD, wait or prompt as written, consequate, record. Mix targets so the client cannot simply alternate. DTT versus naturalistic teaching explains structure. Naturalistic discrimination still requires that the correct cue, not the technician’s hope, controls the response.
Original teaching sketch: Teaching a child to hand over the picture of a shoe when you say “shoe,” and not when you say “book,” is auditory discrimination. Teaching selection of the shoe picture from an array is visual discrimination. Reinforcing both pictures after “shoe” destroys the discrimination.
These sketches are original.
When SD and prompt still swap, use stems that only change which stimulus is extra help.
Errors that look helpful
Reinforcing a response to the S-delta “to keep momentum.”
Always presenting the SD in the same position so location, not the stimulus, controls.
Changing the spoken SD every trial (“find red,” “where’s red,” “rojo”) when the plan required one wording.
The what-to-study guide keeps stimulus control inside Acquisition.
If cue-versus-prompt is the miss, keep a discrimination-only block.
A correct response to the wrong cue is still a miss.
Then mix discrimination items with generalization items so you know when to tighten control and when to loosen it on purpose.
Trust the source
Official sources
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