Classical conditioning is a learning process that was discovered by Ivan Pavlov in the early twentieth century. Pavlov conducted an experiment in which he made a sound right before giving food to some dogs. The dogs would begin to salivate when they knew they were going to get some food. After doing this a few times, Pavlov noticed that the dogs would salivate as soon as they heard the sound, even if there was no food in front of them (Stangor, 2011, pp. 198-199). Pavlov created a set of terms to explain this phenomenon. The sound, when not associated with food, was called a neutral stimulus (NS). The food was an unconditioned stimulus (UCS) and the dogs' salivation was an unconditioned response (UCR). When the sound was repeatedly associated with food, it became a conditioned stimulus (CS). When the dogs salivated in response to the sound (without food being present), this was known as a conditioned response (CR).
A real-life experience of this kind of conditioning occurred for me when I noticed TV commercials for a new fruit smoothie being offered at McDonald's. One day, I decided to try a smoothie. The smoothie had a delicious taste and it gave me a cold, smooth sensation on my tongue. I liked the drink so much that I had it again the next couple of times that I went to McDonald's. Then, I saw the commercial on TV again. I immediately experienced the sensation of my favorite smoothie on my tongue, even though I was not actually drinking one. Thus, the TV ad before I tried the smoothie was a neutral stimulus (NS). The smoothie that I got at McDonald's was an unconditioned stimulus (UCS). The sensation of the smoothie on my tongue was an unconditioned response (UCR). After enjoying a few smoothies, the TV ad became a conditioned stimulus (CS). When the TV ad caused me to experience the taste of the smoothie, this was a conditioned response (CR).
Stangor, C. (2011). Introduction to psychology. Flat W
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