Pavlovian and Operant Conditioning
Jack Kloecker
Cathedral Preparatory School
Pavlovian and Operant Conditioning
“Associative learning takes place by making an association between two stimulus events” (Ettinger, 2009, p.213). It can be categorized in two primary ways: through Pavlovian conditioning and through operant conditioning. Each involve stimulus which provide repeats in the brain. Therefore, they cause something to be learned by the subject. Though very similar end results, both are unique processes in their own aspect.
“Pavlovian conditioning rarely occurs at a conscious level” (Ettinger, 2009, p.214). Subjects often do not realize they have gone through the Pavlovian conditioning process. In fact, Ivan Pavlov, the founder of Pavlovian conditioning, was trying to research on physiological mechanisms on digestion, not with psychology itself. What Pavlov discovered was quite beyond what he was originally researching.
Pavlov was investigating the salivation responses of dogs by placing animals in a harness. A surgical procedure exposed each dog’s salivary glands, which were connected to a device that measured the amount of saliva they produced. Pavlov would then present a stimulus to the dogs, meat powder. Once the food entered the dog’s mouth, then it would begin to salivate. But, another variable came into play.
When Pavlov or his lab assistant would enter the room, the dogs would begin to salivate, even without the presence of food. “The sound of Pavlov’s footsteps or the sight of the food dish also caused salivation” (Ettinger, 2009, p.214). This new discovery changed the whole course of his experiments. Now, he began to focus on how other stimuli could cause dogs to salivate. Through his experiments, psychologists find the first study of learning in the brain.
The food was an unconditioned stimulus meaning it is a stimulus which causes an unlearned response or reflex. The dog salivating was an unconditioned response because it was a stimulus reaction which required no learning. “In behaviorist terms, the lab assistant was originally a neutral stimulus” (McLeod, 2013). A neutral stimulus is a stimulus which causes no response, such as the lab assistant or Pavlov.
What had happened was the neutral stimulus(the lab assistant) had become associated with an unconditioned stimulus(the food). In order to test this, Pavlov tried different neutral stimuli. He first began with a bell. The hungry dog, which is strapped in the harness, hears a bell then is given a steak, which causes salivation. After the experiment is repeated several times, the dog begins to salivate to the sound of the bell.
The dog learned to associate the bell with food, but yet, it is more than just the association between the two stimuli. “Pavlovian conditioning may be best described as the learning of relations among events so as to allow the organism to represent it’s environment” (Rescorla, 1988a). Pavlov’s dog learned to survive in it’s environment. The bell signaled to the dog the availability of food, which is a basic survival instinct.
Once the dog learned to respond to the bell, or neutral stimulus, the stimulus has now become a conditioned stimulus. And the dog’s response has now become a conditioned response. Through development and association between the stimulus, a learning event has occurred. Therefore, Pavlovian conditioning has taken place.
Through Pavlov’s experiments, enough information can be gathered in order to categorize them into three stages: Before Conditioning, During Conditioning, and After Conditioning. “At each stage the stimuli and responses are given special scientific terms” (McLeod, 2014). In Before Conditioning, the unconditioned stimulus produces an unconditioned response in the organism. In basic terms, the stimulus caused a natural response in the subject. Also, the neutral stimulus is in this stage but has no effect on the subject. In During Conditioning, a neutral stimulus is associated with the unconditioned stimulus at which point has now become the conditioned stimulus. At this point, the two stimuli are being associated on multiple trials in order for learning to occur, which is not always the case.
“One trail learning can happen on certain occasions when it is not necessary for an association to be strengthened over time” (McLeod, 2014). For instance, someone goes out to eat at a bar and comes home. On the same night, they throw up from food poisoning. This response can strengthen the association well beyond many trials in order to learn not to eat at the bar. Another example could be a 21 year-old on their birthday. After a full night of drinking multiple different alcoholic beverages, the person throws up all next morning. So in certain cases, there does not have to be multiple reoccurances in order for learning to take place.
During the third and last stage of Pavlovian conditioning, After Conditioning, now the conditioned stimulus has been associated with the unconditioned stimulus to form a new conditioned response. “For example, a person (CS) who has been associated with nice perfume (UCS) is now found attractive (CR). Also chocolate (CS) which was eaten before a person was sick with a virus (UCS) is now produces a response of nausea (CR)” (McLeod, 2014). After all of the stages have occurred, the subject has now learned to adapt to the unconditioned stimulus with a conditioned response.
Pavlov found this out through dogs, but another pair of scientists set out to see if this is true for humans. “Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in and I’ll guarantee to take any one at random and train him to become any type of specialist I might select – doctor, lawyer, artist, merchant-chief and, yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations and the race of his ancestors†(Watson, 1924, p. 104). Watson and Rayner tested this theory on a little baby named Albert. Little Albert was a 9-month-old infant who was tested on with multiple stimuli. He was shown a white rat, a rabbit, a monkey and various masks. Albert showed no fear when the animals were presented to him.
However, what did scare him was when he was shown an animal, someone struck a steel bar with a hammer behind his head. When Little Albert was just over 11 months old, the white rat was presented and seconds later the hammer was struck against the steel bar. This was done 7 times over the next 7 weeks and each time Little Albert burst into tears. By now, Albert only had to see the rat and he immediately showed every sign of fear. He would cry (whether or not the hammer was hit against the steel bar) and he would attempt to crawl away. Pavlovian conditioning has occurred.
Through Pavlovian conditioning, both animals and humans alike learn through associating two stimuli to learn a new behavior, but behaviors can also be learned another way. Though Pavlovian conditioning is very common in daily life, another conditioning method helps us make decisions and helps us learn. This type of associative learning is called operant conditioning.
“Operant conditioning takes place when behavior is influenced by its consequences” (Ettinger, 2009, p. 224). Through Pavlov, we obtained Pavlovian conditioning, but through Edward Thorndike, an American psychologist, we obtained operant conditioning. Pavlov was studying involuntary responses, whereas Thorndike was studying the effects of stimuli on voluntary behavior. “Thorndike believed that animals learn to make voluntary responses that help them adapt to their environment” (Ettinger, 2009, p. 224).
In order to test his theory, Thorndike used cats. He would place hungry cats in a wooden puzzle box which had a latch on it to open it. He then would dangle a piece of fish in their view in order for them to try to escape. Once they were placed in the box, he would time the amount time it takes for them to escape. The cats tried different ways to escape, but most of them just meowed and cried. But eventually, they would trip over the lever and open the box.
After the cat had escaped, Thorndike would then place them back into the box and set the door shut again. Then the process would repeat, except the time would shorten. The cats began to learn that pressing the lever gave good results, or rewards and they would adopt the new behavior. The cats became quicker at escaping. Through these experiments, Thorndike proved his theory which shows the cats would learn to make responses themselves(not involuntarily) in order to adapt to their environment.
“Edward Thorndike put forward a “Law of Effect†which stated that any behavior that is followed by pleasant consequences is likely to be repeated, and any behavior followed by unpleasant consequences is likely to be stopped” (McLeod, 2007). Not only did Thorndike set the foundations for what psychologists know about operant conditioning, but another psychologist, named B. F. Skinner, added to it as well. His research spanned over several decades and has contributed to what we mainly know about operant conditioning. Most of the basic principles of operant conditioning can be showed through one of Skinner’s basic demonstrations.
“Skinner introduced a new term into the Law of Effect – Reinforcement. Behavior which is reinforced tends to be repeated (i.e. strengthened); behavior which is not reinforced tends to die out-or be extinguished (i.e. weakened)” (McLeod, 2007). Skinner showed this by using what he called a “Skinner box”. Like Thorndike’s puzzle box, Skinner had a box which a rat would be placed in. Just like the cat, the rat would run around and if it hit the lever, food pellets would come out.
This is a type of operant called a reinforcer. Reinforcers are responses from the environment which increase the probability of a behavior being repeated. These can be either positive or negative. When the rat would hit the lever and then get a reward, this would be considered a positive reinforcement. “Positive reinforcement strengthens a behavior by providing a consequence an individual finds rewarding” (McLeod, 2007). For example, a college student raises their hand and asks a questions. Once they do, they get applauded. They then become more likely to raise their hand and ask questions because of the reward of applause.
Removing an unpleasant reinforcer can also strengthen behavior. This is known as a negative reinforcement. Skinner showed this by placing a rat in his box, but it had an electric current in it which was very uncomfortable to the rat. The only way to shut it off was the lever. Just as the positive reinforcer, the rat learned to shut the lever off because it took away the current. Skinner also taught the rats to avoid the electric current by turning on a light just before the current came on. The rats would press the lever because they knew it would turn off the current before it started. The light and the current represents Escape Learning and Avoidance Learning.
Besides reinforcers, punishes can weaken a behavior. Punishers are designed to weaken a response or eliminate it in total, whereas reinforcers increase a response. “Punishment can work either by directly applying an unpleasant stimulus like a shock after a response or by removing a potentially rewarding stimulus” McLeod, 2007). Keep in mind, negative reinforcement is not the same as punishment. Negative reinforcement always increases the chances of a behavior to occur, but a punishment decreases the chances of a behavior to occur.
A positive punishment is when an aversive stimulus is presented after a behavior has occurred. For instance, a teacher might yell at a kid when they are talking out of turn. A negative punishment is when a desirable stimulus is taken away after a behavior has occurred. Instead of yelling at the child for talking out of turn, a teacher might take away their recess privileges. In both examples, a behavior is suppressed rather than increased.
Punishments have there drawbacks though. Punished behavior is not forgotten, it is suppressed so if the punishment is not there, then the behavior will come back. Punishers also create fear to particular behaviors, such as fear of school for children. Punishments can also show how aggression is a way to cope with problems, even though that is not always the case. “(Punishment)Does not necessarily guide toward desired behavior – reinforcement tells you what to do, punishment only tells you what not to do” (McLeod, 2007).
In conclusion, Pavlovian conditioning involves learning an association between two stimuli and results in a change in behavior. Operant conditioning involves learning to associate a subjects own behavior with it’s consequences, which causes a change in behavior. Through both operant conditioning and Pavlovian conditioning, learning occurs in the subject. Wether it occurs in an animal or in a human, a new behavior is the outcome.
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