What is the process of stimulus discrimination?

Different consequences may follow the same behavior in different situations. When we respond differently in those different situations, we have formed a discrimination between the situations. For instance, when you tell a ribald tale to friends at a party, but refrain from doing so at a church gathering, this is an example of discrimination. A past history of positive reinforcement in the first case and a past history of positive punishment in the second could clearly be responsible for this illustration of discriminative responding.

Failure to have discriminated between these different situations would represent a case of inappropriate stimulus generalization.

Discrimination comes about when you chose the content of your joke depending on who is the listener (e.g., friend versus priest). Based on the joke that you tell, the positive reinforcement of the listener's laughter or the positive punishment of the listener's frown can tell you whether or not you made the right choice in the joke told.



Discrimination results when different situations occasion different responses based on the contingencies of reinforcement. Inappropriate stimulus generalization occurs when those different situations fail to produce discriminative operant responding. Generalization is not always inappropriate and occurs when you respond the same to two stimuli that are not identical.

For example, a child may learn to say "dog" when it sees the drawing of a rottweiler in a book. If the child later says "dog" when it sees a schnauzer on the street, it has generalized between the two distinct stimuli (the rottweiler and the schnauzer).

Discrimination and generalization are behavioral processes that said to jointly produce conceptual behavior.

Glossary Index

Stimulus Discrimination is when we learn to respond only to the original stimulus, and not to other similar stimuli. The concept of Stimulus Discrimination follows from the idea of Stimulus Generalization, which is when we respond not only to the original stimulus, but also to other similar stimuli.

For example, whenever you come home from work, the first thing you do is feed your dog. As a result, your dog gets excited as soon as he hears your car pulling up at the driveway, barking and running to the door. Eventually, he begins to get excited as soon as any family member arrives in their car, thinking that he will get fed as well. Everytime he hears any car pull up at the driveway, he starts barking and running to the door. That is Stimulus Generalization. But if none of the other family members ever feed the dog as soon as they arrive home, your dog eventually learns that it is only the sound of your car pulling up at the driveway that's worth getting excited about. That is Stimulus Discrimination, because he learns to distinguish only the specific sound that means food is coming, and learns to ignore all other car sounds as not relevant to his getting fed.

Stimulus Control

Learning Activities

1.    Definitions

2.    Identify concepts from video clips (Refer to Clucking Calculator.)

3.    Provide your own examples

4.    Crossword puzzle

5.      Word search

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Discrimination Training

What is the process of stimulus discrimination?

Discrimination training involves reinforcing a behavior (e.g., pecking) in the presence of one stimulus but not others. In the picture to the left, one of the Bailey�s chickens was presented with two note cards; one card contained a red circle, while the other card contained a blue circle. A peck on the red circle was reinforced, while a peck on the blue circle was not reinforced (this process involves differential reinforcement). Eventually, the chicken only pecked the red circle. The Baileys also used note cards with different shapes (e.g., circles v. squares) to demonstrate discrimination training involving geometric figures. With discrimination training, animals like chickens are said, in everyday language, to be able to "tell the difference" between shapes (like circles or squares) or colors (like red or blue), as long as the animal has the appropriate sensory apparatus, like color vision.

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Discriminative Stimulus (and Generalization)

What is the process of stimulus discrimination?

The discriminative stimulus is the cue (stimulus) that is present when the behavior is reinforced. The animal learns to exhibit the behavior in the presence of the discriminative stimulus. In the example above, the red circle was the discriminative stimulus (sometimes abbreviated SD,pronounced "S-Dee".) In the case of note cards with squares and circles, if the Baileys had reinforced pecking a square rather than a circle, the SD would have been the square. (To complicate the matter, animal trainers like to call the SD the "hot stimulus," because behaving in the presence of that stimulus will get the animal a reinforcer.) Further, the animal does not have to interact with the discriminative stimulus - for example, in the post-card vending chicken, a light signals the availability of reinforcement, but the chicken does not have to interact with the light and only has to pull a loop. Refer to the picture to the left. The staff of ABE often used "targets" to help control the behavior of animals. In many demonstrations, the animals were taught to touch the target with their noses. These targets were "hot" stimuli and, therefore, discriminative stimuli. In short, discriminative stimuli occur before the behavior and are said to control the behavior (refer back to the three-term contingency). (Generalization occurs when the animal responds to stimuli that are similar to the SD, but not exactly the same stimuli that were used in training � for example, to red circles of slightly different hues, to lines of slightly different lengths, to circles of slightly different diameters.)

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What is the process of stimulus discrimination?

The S-delta (SD) is the stimulus in the presence of which the behavior is not reinforced. At first during discrimination training, the animal often responds in the presence of stimuli that are similar to the SD. These similar stimuli are S-deltas. Eventually, responding to the S-delta will be extinguished. (Animal trainers call the S-delta the "cold stimulus.")Let's take the example of pecking a red circle. The trainer makes two cards, one with a red circle and one with blue circle. Pecking the red circle is reinforced, but not pecking the blue circle. (At first, the chicken might peck both circles, but if pecking is only reinforced in the presence of the red circle, pecking will eventually occur only in the presence of that circle.) The blue circle would be an S-delta. 

What is a stimulus discrimination procedure?

Stimulus discrimination training is a strategy that is used to teach an individual to engage in particular behaviors in the presence of certain situations, events, or stimuli.

What are the two steps in stimulus discrimination training?

Answer = The following two steps are involved in stimulus discrimination training: a) When the discriminative stimulus (S D ) is present, the behaviour is reinforced; and b) When any other antecedent stimuli are present except S D , the behaviour does not get reinforced.

How is the process of stimulus generalization and stimulus discrimination considered opposite?

Stimulus generalization occurs when a stimulus that is similar to an already-conditioned stimulus begins to produce the same response as the original stimulus does. Stimulus discrimination occurs when the organism learns to differentiate between the CS and other similar stimuli.