Each stimulus change in a behavior chain serves as an SD for the subsequent response and as a conditioned reinforcer for the preceding response. True or False?

• A. True
• B. False
• C. Not sure
• D. Depends

Answer: (B)

In a behavior chain, each response produces a stimulus change that signals the next step by functioning as an SD for the upcoming response. That same stimulus change can also become a conditioned reinforcer for the response that produced it, because it has acquired reinforcing properties through its connection to the chain’s progression toward the final reinforcement. However, there’s an important exception: the very first stimulus change has no preceding response to reinforce, so it cannot serve as a conditioned reinforcer for a prior action. Because the statement claims that every stimulus change plays both roles, it overgeneralizes and isn’t accurate.