Now, anyone who has had a dog and has a routine for walking them will know that their dog will learn the time of day and wait, sometimes lead in mouth, at the door for their routine walk.
Each time he presented the food to the dogs he rang a bell. After a while he found that ringing the bell alone could induce salivation in the absence of food. He called this classical conditioning and it has become an explanation of why people behave in certain ways. For example many people have phobias. A person climbing to a high place and looking down may feel dizzy and uncomfortable and then develop a phobia of heights because they have developed an association between high places and physical discomfort.
Then they repeated the experiment presenting the animals to Albert and clanging a large bar at the same time. The loud noise made the baby cry.
ON the third repeat of the experiment they just presented the animals again. This time Albert shied away from the animals and cried. Just like the dogs he had learned to associate one stimulus furry animals with a loud noise. No one knows what happened to Little Albert, but the poor lad probably had a phobia of white animals for the rest of his life!
Behaviourists offered an alternative to the Freudian approach to managing pathologies of the mind. Behaviourism suggests that undesirable behaviours can be discourages and helpful behaviours can be encouraged by the appropriate application of stimuli and rewards. This is the basis of many parenting manuals even today. Todes, a professor of the history of medicine at Johns Hopkins School of Medicine.
In fact, much of what we thought we knew about Pavlov has been based on bad translations and basic misconceptions. That begins with the popular image of a dog slavering at the ringing of a bell. Pavlov is perhaps best known for introducing the idea of the conditioned reflex, although Todes notes that he never used that term. For Pavlov, the emphasis fell on the contingent, provisional nature of the association—which enlisted other reflexes he believed to be natural and unvarying.
Such conjectures about brain circuitry were anathema to the behaviorists, who were inclined to view the mind as a black box. Nothing mattered, in their view, that could not be observed and measured. Pavlov never subscribed to that theory, or shared their disregard for subjective experience. Pavlov believed that it started with data, and he found that data in the saliva of dogs. By creating additional fistulas along the digestive system and collecting the various secretions, he could measure their quantity and chemical properties in great detail.
That research won him the Nobel Prize in Physiology or Medicine. All human resources—art, religion, literature, philosophy, and the historical sciences—all have joined in the attempt to throw light upon this darkness. But humanity has at its disposal yet another powerful resource—natural science with its strict objective methods.
Pavlov had become a spokesman for the scientific method, but he was not averse to generalizing from his results. Ivan Pavlov was born in in the provincial Russian city of Ryazan, the first of ten children.
As the son of a priest, he attended church schools and the theological seminary. But he struggled with religion from an early age and, in , left the seminary to study physiology and chemistry at St. Petersburg University. His father was furious, but Pavlov was undeterred. He never felt comfortable with his parents—or, as this biography makes clear, with almost anyone else. Pavlov entered the intellectual world of St. Petersburg at an ideal moment for a man eager to explore the rules that govern the material world.
The tsar had freed the serfs in , helping to push Russia into the convulsive century that followed. The Soviets would soon assign religion to the dustbin of history, but Pavlov got there ahead of them. For him, there was no religion except the truth. Pavlov was not a pleasant person. Todes presents him as a volatile child, a difficult student, and, frequently, a nasty adult.
As a member of the liberal intelligentsia, he was opposed to restrictive measures aimed at Jews, but in his personal life he freely voiced anti-Semitic sentiments. In lectures, Pavlov insisted that medicine had to be grounded in science, on data that could be explained, verified, and analyzed, and on studies that could be repeated. To study them, he introduced a rigorous experimental approach that helped transform medical research. He recognized that meaningful changes in physiology could be assessed only over time.
The conditioned stimulus is usually neutral and produces no particular response at first, but after conditioning it elicits the conditioned response. Extinction is the decrease in the conditioned response when the unconditioned stimulus is no longer presented with the conditioned stimulus.
When presented with the conditioned stimulus alone, the individual would show a weaker and weaker response, and finally no response. In classical-conditioning terms, there is a gradual weakening and disappearance of the conditioned response. Related to this, spontaneous recovery refers to the return of a previously extinguished conditioned response following a rest period. Pavlov was originally studying the saliva of dogs as it related to digestion, but as he conducted his research, he noticed that the dogs would begin to salivate every time he entered the room—even if he had no food.
The dogs were associating his entrance into the room with being fed. This led Pavlov to design a series of experiments in which he used various sound objects, such as a buzzer, to condition the salivation response in dogs.
He started by sounding a buzzer each time food was given to the dogs and found that the dogs would start salivating immediately after hearing the buzzer—even before seeing the food.
After a period of time, Pavlov began sounding the buzzer without giving any food at all and found that the dogs continued to salivate at the sound of the buzzer even in the absence of food. They had learned to associate the sound of the buzzer with being fed. Pavlov had successfully associated an unconditioned response natural salivation in response to food with a conditioned stimulus a buzzer , eventually creating a conditioned response salivation in response to a buzzer.
With these results, Pavlov established his theory of classical conditioning. Classical conditioning : Before conditioning, an unconditioned stimulus food produces an unconditioned response salivation , and a neutral stimulus bell does not have an effect. During conditioning, the unconditioned stimulus food is presented repeatedly just after the presentation of the neutral stimulus bell. After conditioning, the neutral stimulus alone produces a conditioned response salivation , thus becoming a conditioned stimulus.
Consider how the conditioned response occurs in the brain. When a dog sees food, the visual and olfactory stimuli send information to the brain through their respective neural pathways, ultimately activating the salivation glands to secrete saliva. This reaction is a natural biological process as saliva aids in the digestion of food. When a dog hears a buzzer and at the same time sees food, the auditory stimulus activates the associated neural pathways.
However, because these pathways are being activated at the same time as the other neural pathways, there are weak synapse reactions that occur between the auditory stimulus and the behavioral response. Over time, these synapses are strengthened so that it only takes the sound of a buzzer or a bell to activate the pathway leading to salivation. Eysench then extended the research to human personality traits.
Desensitizing is a kind of reverse conditioning in which an individual is repeatedly exposed to the thing that is causing the anxiety. Flooding is similar in that it exposes an individual to the thing causing the anxiety, but it does so in a more intense and prolonged way. Research has demonstrated the effectiveness of classical conditioning in altering human behavior.
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