Final answer:
In Pavlov's experiment, a buzzer or tone serves as a neutral stimulus that becomes a conditioned stimulus, meaning it initially doesn't elicit a response but after being paired with an unconditioned stimulus, it triggers a conditioned response.
Step-by-step explanation:
In a typical classical conditioning experiment by Pavlov, a buzzer or tone serves as a neutral stimulus that becomes a conditioned stimulus (C). Initially, the tone is a neutral stimulus; it does not elicit any particular response from the dogs. During the conditioning process, the tone is repeatedly paired with an unconditioned stimulus (the meat powder which naturally causes salivation). Over time, the tone becomes a conditioned stimulus as the dogs begin to salivate in response to the tone alone, anticipating the food that has been paired with it in the past. This learned response to the conditioned stimulus is known as the conditioned response.