In pavlov's original classical conditioning experiments, the was the neutral stimulus, the was the stimulus that would elicit a reflex, and was the reflexive response.

bell; meat powder; salivation

Explanation:

Ivan Pavlov: He was a Russian physiologist who discovered Classical Conditioning. While studying the digestive systems of dogs, he noticed that after the presentation of food the animals salivated naturally.

He demonstrated a study, in which while feeding the dogs he rang a bell. Soon the dogs salivated only after ringing the bell. Pavlov believed the dogs were exhibiting classical conditioning. He summarized that there's a neutral stimulus i.e the bell which will not produce a response itself as salivation does.

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