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VII. Classical Conditioning a. Definition i. A form of associative learning. Associative learning is a process by which an element is learned through association with a separate event. ii. Classical Conditioning is also related to Behaviorism. Behaviorism is the idea that learning occurs through interactions with the environment. b. Origins / Discovery i. Classical Conditioning (CC) was originally studied under the behaviorist tradition. ii. First described by Ivan Pavlov 1. Russian scientist -> skilled in biology and medicine 2. Was studying the digestion of dogs 3. Found out that dogs that had been deprived of food, would begin to salivate when his assistant entered the room (as he was the one that fed the dogs) 4. This spawned multiple experiments and led to the first full description of classical conditioning 5. Skinner later renamed this type of learning 'Respondent Conditioning' as the subject responds to a stimulus. c. Main aspects i. Unconditioned Stimulus (US) 1. A stimulus is defined specifically as 'something' that causes a response. This is actually a good definition as in CC, the US is anything that elicits a natural (automatic) response. 2. Using Pavlov's dogs example, the US is the food. ii. Unconditioned Response (UR) 1. This is the unlearned response that comes naturally, directly, and automatically as a result of the US. It is important to note that the response in unlearned, as the CR will end up being the learned response. 2. If the US is food, the UR is the dog beginning to drool or salivate as a result of the food. Or simply put, food causes dogs to drool. For us, this might be the feeling of hunger when discussing our favorite meal. iii. Neutral Stimulus (NS) 1. The NS is some sort of occurrence that does not elicit a response - or at the very least does not elicit the UR. 2. In Pavlov's experiments, he used a metronome (time keeping, musical clicking device) to train the dogs that food was coming. A dog dish has also been used to explain a neutral stimulus. 3. Either a metronome or a dog bowl would not cause a dog to begin to salivate. iv. Conditioned Stimulus (CS) 1. It is only when a NS is consistently paired with a US, that learning occurs. The CS was previous the NS - but as it is paired with the US, the conditioning occurs. 2. The conditioning is the learning process. The NS eventually becomes the trigger for a conditioned response. 3. With the dogs, every time the metronome was brought out, food followed immediately. This meant that because the NS was always paired with food, the dogs learned that as soon as it was brought out, the food would come. v. Conditioned Response (CR) 1. The CR is the learned response to the previously neutral stimulus. The CR will be the same reaction as the UR, but now the reaction will be happening to the NS. 2. For the dogs, now they begin salivating to a metronome or a dog bowl neither of which had elicited a response prior. vi. Acquisition 1. This is the period of time (or number of times) when the [previously] neutral stimulus comes to evoke the expected response. 2. Put another way, this is how quickly one conditions (or learns) that the NS will always be paired with the US. Hence, they will provide the now conditioned response. 3. For instance, how long did it take for the dogs to learn that every time the metronome came out, that meant food was coming? That is the acquisition time. vii. Extinction 1. This refers to the decline of a conditioned response when a conditioned stimulus repeatedly occurs without the presence of the unconditioned stimulus it had been paired with. 2. Essentially this is how quickly one 'forgets' how they are supposed to react to a stimulus. 3. For the dogs, if the metronome is brought out at random times and the food does not follow, the dogs may start drooling at first, but will then realize that the food is not coming. Eventually, the dogs will no longer react to the metronome. viii. Stimulus generalization 1. The tendency for the conditioned stimulus to evoke similar responses after the response has been conditioned. 2. For example, if a rat has been conditioned to fear a stuffed white rabbit, it will exhibit fear of objects similar to the conditioned stimulus. d. Higher Order Conditioning i. Sometimes called second-order conditioning. ii. Once a subject has been conditioned to respond to a neutral stimulus, a second neutral stimulus is then added to the process. iii. For example - if Pavlov's dogs have learned to associate a metronome with food, they then might learn to associate a light with the metronome. e. The 'Little Albert' Experiment i. Albert was chosen to be a participant for a classical conditioning study at the age of nine months. ii. He was given a battery of tests to see if he had any reaction to a number of stimuli (including: a white rat, a rabbit, a dog, a monkey, masks with and without hair, cotton wool, burning newspapers, etc.) iii. Albert showed no fear of any of these items. iv. At 11 months, Albert was placed on a mattress with a white laboratory rat. Albert showed no fear of the rat and even would reach out to play with it. v. After several trials, the scientist (John Watson) would strike a metal bar with a hammer every time Albert reached for the rat. Little Albert cried and showed fear when he heard the noise. vi. After several such trials, whenever the rat was brought out, Albert became severely distressed and began to cry and move away from the rat. vii. This is a classic example of classical conditioning and shows how a subject can learn to fear a previously neutral stimulus. viii. Unfortunately, Albert's fear of rats generalized to include white rabbits, white puppies, Santa Claus and cotton balls. f. Classical Conditioning in real life i. People generally do not respond to classical conditioning (except maybe at a young age) but there are real world applications. ii. Many times animals can be trained using CC as base. For example, many dog trainers use classical conditioning techniques to help people train their pets. iii. These techniques are also useful in the treatment of phobias or anxiety problems. iv. Teachers are able to apply classical conditioning in the class by creating a positive classroom environment to help students overcome anxiety or fear. Pairing an anxiety-provoking situation, such as performing in front of a group, with pleasant surroundings helps the student learn new associations. Instead of feeling anxious and tense in these situations, the child will learn to stay relaxed and calm.