Which term describes antecedent stimuli that evoke imitation and are not intentionally shown as models?

• A. Planned models
• B. S-deltas
• C. Unplanned models
• D. Generalization stimuli

Answer: (C)

When we think about imitation, the trigger is a stimulus that invites the observer to copy a behavior. If the model isn’t intentionally shown as a teaching moment—that is, the person sees someone perform a behavior by chance or in a natural setting—those antecedent stimuli are best described as unplanned models. They still cue imitation because the observer has learned that similar actions can be followed by reinforcement or by others’ responses, even though no formal demonstration was provided.

This contrasts with planned models, where someone deliberately demonstrates the behavior for the learner. It also differs from a discriminative signal like an S-delta, which points to non-reinforcement in a given situation, and from generalization stimuli, which evoke similar responses due to stimulus similarity rather than due to an observed model. Recognizing unplanned models helps explain how imitation can occur outside structured teaching moments, shaping how environments influence learning through observation.