Classical conditioning (or Pavlovian conditioning ) is one of the introductory topics studied in career psychology, and is one of the basic learning principles.
Therefore, certainly all psychologists and teachers are aware of its importance in associative learning or in the formation of pathologies such as phobias . There are few who are not familiar with Ivan Pavlov and his experiments with dogs. For those who don’t know him yet, we explain his theory in detail below.
Classical conditioning explained
One of the most important features of this type of learning is that it involves automatic or reflexive responses, not voluntary behaviors (as opposed to operant or instrumental conditioning) . It has been called “classical conditioning” for creating a connection between a new stimulus and an existing reflex; therefore, it is a type of learning according to which an originally neutral stimulus, which does not cause a response , can provoke it thanks to the associative connection of this stimulus with the stimulus that normally provokes this response.
Classical conditioning laid the foundations of behaviorism , one of the most important schools of psychology, and was born as a result of the studies of Pavlov, a Russian psychologist interested in the physiology of digestion, especially the salivation reflexes in dogs.
Pavlov’s famous dog experiment: the conditioned reflex
Pavlov’s research is one of the foundations of the behavioral sciences. In his initial investigations, Pavlov observed that after he had put food in the mouth of the dog he was investigating, it began to secrete saliva from certain glands . Pavlov called this phenomenon the “salivation reflex”.
When performing the experiment repeatedly, he observed that his presence (that of Pavlov himself) caused the dog to start secreting saliva without having food present, as it learned that when Pavlov presented himself at the laboratory, he would be given food . So, to find out if he was right, he put a separator between the dog and the food, so the dog couldn’t see it. The researcher introduced the food through a hatch and recorded the animal’s salivation.
Later, Pavlov started to apply different stimuli (auditory and visual) that were neutral, just before serving the dog food. Results from it indicated that, after several applications, the animal associated the stimuli (now conditioned stimuli) with food. Pavlov called the salivation that occurred after this association a “conditioned reflex”.
Below you can watch this video that explains Pavlov’s experiments.
The theory of classical conditioning: general concepts
Classical conditioning is also called stimulus-response model or association learning (ER) . The results of his research earned Pavlov the Nobel Prize in 1904.
In the process, he designed the classical conditioning scheme from his observations:
- The unconditioned stimulus (US) is a stimulus that automatically triggers a response from the organism.
- The unconditioned response (IR) is the response that automatically occurs in the body when an unconditioned stimulus is present. For Pavlov, it would be the amount of saliva the dog secreted when food was presented.
- The neutral stimulus (NO) is a stimulus that, when present in the environment, does not cause any response in the body.
- When a neutral stimulus is temporarily associated with an unconditioned stimulus, it becomes a conditional stimulus (CE) , as it is capable of eliciting a response similar to that caused by the unconditioned stimulus.
- The conditional response (CR) is the response that appears when only the conditioned stimulus is presented. For Pavlov, it would be the amount of saliva that the dogs secreted when they received only the auditory or visual stimulus.
- Generally , CR is weaker than IR and has a longer latency , that is, it takes longer to occur when the stimulus is present.
Watson’s contributions to behaviorism
Fascinated by Pavlov’s discoveries, John Watson proposed that the process of classical conditioning could also explain learning in humans. As a classical behaviorist, he thought that emotions were also learned through conditioned association and, in fact, he thought that differences in human behavior were caused by the different experiences that people had.
The Little Albert Experiment (by John Watson)
To do this, he carried out “the experiment with little Albert”, an 11-month-old baby, together with his collaborator Rosalie Rayner, at Johns Hopkins University (United States), because he wanted to find out if it is possible to condition an animal when it is associated with a loud noise (hammer blow on a metal plate) that elicits a fear response .
The association of a hammer blow on the metal plate (EI) and the presence of a white rat (CE), which was previously a neutral stimulus, ended up causing an emotional response of fear (CR) in the presence of the rat alone , thus demonstrating that fear can be learned through classical conditioning. This is the most common mechanism of acquiring phobias. Needless to say, such an experiment could not be performed today, as it exceeds the bounds of scientific ethics.
In 1913, Watson published an article called Psychology as the behaviorist sees it and proposed to analyze psychology from the analysis of observable behavior, and not from the analysis of consciousness , a current perspective until then. To that end, he proposed eliminating introspection as a valid method for psychology, replacing it with objective observation and experimentation.
