Humans and other animals are active beings, interacting with an environment on which they depend for survival. But why do we do what we do? How do you explain that, for example, when a dog hears a bell he starts to salivate or because we run to seek refuge when we hear an alarm?
This how and why we act as we act is something that has always been of great scientific interest, and that psychology has studied and researched different theoretical currents. One of them, behaviorism, is considered to be due to a conditioning process. And in this process, the bell or alarm would be lit fulfill the role of conditioned stimulus. It is on this concept, that of the conditioned stimulus, that we will speak throughout this article.
What is a conditioned stimulus?
It receives the name of conditioned stimulus all that element which, being initially neutral and not provoking in the person or the animal any reaction by itself, acquires the property of generate a response to association with another stimulus that generates a reaction.
Using the example used in the introduction, we react with fear to the sound of an alarm, not because the alarm generates a reaction in itself but because we know that this sound is linked to the existence of an alarm. danger or pain (entry of an intruder, 1 enemy attack or fire, for example). In the case of the dog and the bell (As part of Pavlov’s experiments which gave rise to the study of classical conditioning), the dog will begin to salivate at the sound of the bell, associating it with the fact that they are bringing him food (the sound of bell being a conditioned stimulus).
This relationship is produced by the ability to associate between stimuli, which most classical conditioning considered to be specifically specific to the stimulus itself (although today through other currents we know that other aspects such as will, motivation or cognition influence).
There must be a minimum of contingency (That is, the onset of one predicts the onset of another, or they occur to a large extent simultaneously or continuously) between conditioned stimuli and those which enabled a such thing to come back, unconditioned stimuli. Moreover, the response generated by the latter must be strong, and although it is not essential that there can be a relationship between the two.
Almost any type of neutral stimulus can become conditioned as long as it is noticeable. Perception can come from any channel or sense, and can be anything visual (lights, image, etc.), sounds (timbres, voices, specific words, etc.), tactile perceptions (texture, temperature , pressure), tastes or smells. Even in some cases, stimuli that generate a response can be conditioned if they are combined with stimuli that generate a response more relevant to the subject.
Also, as we have seen, conditioning occurs in a large number of living things. It can be observed in humans, but also in dogs, monkeys, cats, mice or pigeons among many others.
The birth of a conditioned stimulus
So, for there to be a conditioned stimulus, there has to be something that conditions it: the unconditioned stimulus that itself generates a response. And the relationship that is established between them is called conditioning. The birth of a conditioned stimulus it occurs in what is called the acquisition phase (In which it acquires the properties which make it pass from neutrality to conditioning).
From the perspective of classical conditioning, one stimulus is conditioned by another due to the generation of a link between the appearance of the initially neutral and unconditioned stimulus, which in itself generates an appetitive or aversive response (called an unconditional response).
Slowly and secondly they are presented together or in a short intervalThe subject makes associations, causing the initially neutral stimulus to acquire appetitive or aversive characteristics and to switch from not generating a response to the one generating the stimulus that elicited a response. Thus, it will eventually generate a conditioned response and the neutral stimulus becomes considered a conditioned stimulus. From now on, the appearance of the conditioned stimulus will generate the same reaction as the unconditioned stimulus.
With possibility of extinction
That a stimulus is conditioned and generates a conditioned response can occur day to day or be provoked voluntarily, but the truth is that this association will tend to be extinguished if the subject observes that the joint appearance of an unconditioned stimulus and conditioning ceases to occur. Thus, the conditioned stimulus it will eventually become neutral again and will no longer generate responses.
This extinction process can be more or less prolonged depending on several factors.
Among them we find the strength of the association between the stimuli or the times when it was repeated, or whether we have learned that the unconditioned stimulus always appears in all situations where the conditioning appears or a large part of the time (well may seem counterintuitive, the association takes longer to turn off if one is used to the fact that the two stimuli do not always appear together).
Of course sometimes spontaneous recoveries may occur from the Association.
Relationship with psychological problems
There are a large number of behavioral problems related to conditioning, particularly with the fact that a stimulus has become a conditioned stimulus and generates a conditioned response.
Usually the presence of a fear or even a phobia it can come into play (although a large number of factors come into play and not only these) with this type of association, if a stimulus has been associated with pain or suffering.
So, if once a dog has bitten us, we can associate any dog with pain, which will make us fear new exposures and avoid them (the dog being the conditioned stimulus). And not just the fear of phobias but that of post-traumatic stress disorder (for example, in people who have been raped, fear of sex or people with characteristics similar to the abuser may appear).
It can also happen in reverse, that one associates something with the pleasure or the avoidance of discontent and that there is an excitement or an excessive appetite for this stimulus, conditioned. For example, conditioning has been used to try to explain certain paraphilias, impulse control disorders, eating disorders or addictions.