Without the _____, higher-order conditioning would be difficult to maintain and would gradually fade away.

• A. conditioned stimulus
• B. neutral stimulus
• C. unconditioned response
• D. unconditioned stimulus

Answer: (D)

Verified step by step guidance

1. Understand the concept of higher-order conditioning: Higher-order conditioning is a process in classical conditioning where a neutral stimulus becomes a conditioned stimulus by being paired with an already established conditioned stimulus.
2. Identify the role of the unconditioned stimulus: In classical conditioning, the unconditioned stimulus (US) is a stimulus that naturally and automatically triggers a response without any prior learning.
3. Recognize the importance of the unconditioned stimulus: The unconditioned stimulus is crucial because it is the original source of the response that is transferred to the conditioned stimulus through the conditioning process.
4. Consider the fading of higher-order conditioning: Without the unconditioned stimulus, the association between the conditioned stimulus and the response would weaken over time, as there would be no reinforcement of the original response.
5. Conclude the necessity of the unconditioned stimulus: Therefore, the unconditioned stimulus is essential for maintaining the strength and persistence of higher-order conditioning, preventing it from fading away.