Questions: Professor Fayed has identified specific neural circuits that link a conditioned stimulus with an upcoming unconditioned stimulus. Their research is clearly influenced by the findings of Winfrey. Tirrell. Skinner. Pavlov.

The answer is the fourth one (or D): Pavlov.

Explanation for each option:

• Winfrey: There is no well-known researcher by the name of Winfrey associated with the study of neural circuits and conditioning in the context provided.
• Tirrell: Similarly, Tirrell is not a recognized name in the field of classical conditioning or neural circuits related to conditioned and unconditioned stimuli.
• Skinner: B.F. Skinner is known for his work in operant conditioning, which involves learning through rewards and punishments, rather than the specific neural circuits linking conditioned and unconditioned stimuli.
• Pavlov: Ivan Pavlov is famous for his research on classical conditioning, where he demonstrated how a neutral stimulus (conditioned stimulus) could be associated with an unconditioned stimulus to produce a conditioned response. This directly relates to the identification of neural circuits linking a conditioned stimulus with an unconditioned stimulus.

Summary: Professor Fayed's research on neural circuits linking a conditioned stimulus with an unconditioned stimulus is influenced by the findings of Pavlov.