How did Ivan Pavlov train dogs to salivate at the sound of a metronome?

To train a dog to salivate at the sound of a metronome, Ivan Pavlov utilized a systematic procedure known as classical conditioning.1

The process involved these steps:

• Restraint: A hungry dog was restrained on a stand to ensure a controlled environment.1
• Pairing: Pavlov presented an unconditional stimulus—dry meat powder—which naturally and invariably elicited salivation (the unconditional response).1
• Signaling: Before the delivery of the food, Pavlov introduced a neutral stimulus, such as the ticking of a metronome.1
• Conditioning: Through repeated trials where the metronome sound consistently preceded the food, the dog began to associate the two events.1
• Result: Eventually, the ticking of the metronome alone became a conditional stimulus, capable of eliciting salivation, which was then termed a conditional response.1

This experiment demonstrated that learning occurs through the temporal relationship between stimuli, allowing an animal to anticipate a biological event based on a previously neutral signal.1