Concepts · Domain B
Discriminative stimulus (Sᴰ) vs. S-delta (SΔ)
The difference in short
The discriminative stimulus (Sᴰ) and S-delta (SΔ) are opposite antecedent signals. With an Sᴰ there's a history of reinforcement being available, so behavior is more likely. With an SΔ reinforcement isn't available, so behavior is less likely.
Quick comparison
| Discriminative stimulus (Sᴰ) | S-delta (SΔ) | |
|---|---|---|
| Operation | Signals reinforcement is available | Signals reinforcement is NOT available |
| Effect | ↑ Behavior is more likely | ↓ Behavior is less likely |
| Example | Green light → you cross the street. | Red light → you don't cross. |
How to tell them apart
- In the stimulus's presence, is there a history of reinforcement (Sᴰ) or non-reinforcement (SΔ)?
Examples
SᴰDiscriminative stimulus
Green light → you cross the street.
SΔS-delta
Red light → you don't cross.
Frequently asked
Does S-delta punish behavior?
No. S-delta adds or removes no consequence; it only signals that reinforcement isn't available, so behavior is simply less likely in its presence.
Related concepts
Discriminative stimulus (Sᴰ) vs. motivating operation (MO)→Stimulus generalization vs. discrimination→
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