The elapsed time from the onset of a stimulus (e.g., task direction, cue) to the initiation of a response.

• A. Response Latency
• B. Response Cost
• C. Repertoire
• D. Respondent Behavior

Answer: (A)

Response latency is the time between when a stimulus is presented and when the person actually starts the response. It specifically measures how quickly a response is initiated after the cue, not how long the response lasts. For example, if a cue signals a student to begin clapping, the elapsed time from the cue to the start of the clap is response latency. This differs from response cost, which is a reinforcement procedure involving loss of a reward; repertoire, the set of behaviors a person can perform; and respondent behavior, which is automatically elicited by antecedent stimuli and not about timing after a cue. So the description matches response latency because it focuses on the interval from stimulus onset to the start of the response.