Ivan Petrovich Pavlov (26 September 1849 – 27 February 1936) was a Russian physiologist known primarily for his work in classical conditioning. Pavlov is primarily known for his work studying the "conditioned reflex" by examining the rates of salivations among dogs. Pavlov had learned that when a buzzer or metronome was sounded in subsequent time with food being presented to the dog in consecutive sequences, the dog would initially salivate when the food was presented. The dog would later come to associate the sound with the presentation of the food and salivate upon the presentation of that stimulus.

In "Stewie, Chris & Brian's Excellent Adventure", Brian requests a side trip thorough time to visit with Pavlov during his experiments on dogs, beating him to death in the process.