According to Pear (1999) As we acquire new behaviors we learn to develop them at the right time and in the right place, the behavior is strongly affected by its consequences, that is, the behavior that is reinforced increases, and the one that does not increase decreases.
We use the term stimulus check to refer to the control of a stimulus over behavior as a result of the behavior being reinforced in the presence of that stimulus. While certain stimuli are consistent predictors that a certain behavior will be reinforced, others are consistent predictors that a particular behavior will not be.
It is probable that behavior takes place in the presence of stimuli that were present when on previous occasions that behavior was reinforced; The procedure by which we learn to emit appropriate behaviors in the presence of certain stimuli is called: stimulus discrimination training. There are names for the 2 types of stimuli associated with reinforcement and non-reinforcement of a given response:
E °: (e-de) It is a stimulus that has been associated with the availability of reinforcement for a particular response, that is, it is an indicator that a response will be rewarded. However, if an event is a stimulus that has been put in relation to extinction tests of a certain response, it is called E * (e-delta ): it is an indicator that a certain response will not be rewarded. E ° is associated with reinforcement_; and E * is associated with non-reinforcement or extinction.
The adequacy of an instrumental response to the stimulating context in which it is performed is so important that the lack of proper stimulus check is often considered abnormal, undressing in private is acceptable in public for reason of arrest.
Control of behavior by stimulation is an important aspect of how organisms adapt to the environment. To accommodate effectively and avoid danger, animals have to behave consistently with changing circumstances. How can one affirm that an instrumental response is under the control of certain stimuli?
Differential response and stimulus discrimination
Control by stimulation of instrumental behavior is demonstrated by variations in response (differential response) related to variations in stimuli. If an organism responds one way in the presence of one stimulus, and differently in the presence of another, it can be said that its behavior is under the control of those stimuli. These differential responses are evident in the behavior of the two pigeons from the Reynolds experiment.
The differential response to two stimuli also indicates that the pigeons were treating each stimulus differently. This is called stimulus discrimination: An organism is said to show stimulus discrimination if it responds differently to two or more stimuli. Stimulus discrimination and stimulus check are two ways of looking at the same phenomenon: one does not exist without the other. If an organism does not discriminate between two stimuli, its behavior is not under the control of those keys.
Another interesting aspect of Reynolds’ experiment is that the behavior of each bird was controlled by a different stimulus.
In the absence of special procedures, researchers cannot always predict which of several stimuli from which an organism experiences will acquire control over its instrumental behavior.
Identifying and differentiating various stimuli is not so simple. Stimuli can be defined in many different ways. Sometimes very different objects or events are considered examples of the same stimulus because they share the same function. In other cases, stimuli are identified and distinguished based on precise physical features, such as wavelength.
Experimental analyzes of the problem have largely depended on the phenomenon of stimulus generalization, which is the opposite of differential response, or stimulus discrimination. An organism is said to show stimulus generalization if it responds similarly to two or more stimuli. This phenomenon was first observed by Pavlov.
In a classic experiment, Guttman and Kalish pigeons program IV pecked with yellowish light with a wavelength of 580 nanometers, then it was observed that pigeons also responded to 570 and 590. These results showed a response gradient depending on the similarity between each test stimulus. and the original training stimulus. This result is an example of what is called the stimulus generalization gradient.
Stimulus generalization gradients as measures of stimulus check
They are often used to measure stimulus checks because they provide information about the degree of sensitivity of an organism’s behavior to variation in a particular aspect of the environment.
Guttman and Kalish (1956) and the hypothetical experiment with color blind pigeons indicates that the sharpness of the stimulus generalization gradient provides an accurate measure of the degree of stimulus check. A flat generalization gradient is obtained if the organism responds similarly to all stimuli in the test. This lack of differential response demonstrates that the stimulus trait that is varied in the generalization test does not check instrumental behavior. On the contrary, a sharp generalization gradient is obtained if the organism responds more to some of the test stimuli than to others. This differential response evidences the fact that instrumental behavior is under the check of the stimulus trait that varies between test stimuli.
If there is a large amount of generalization, there will be little differential response. If the response is highly differential before the stimuli, a minimum generalization will be obtained.
The factors that determine the effectiveness of training in stimulus discrimination are: the choice of clear signals for when it is important to develop control of the stimulus of a certain behavior, it is desirable to identify the E ° drivers are very clear.
2- Minimize the possibilities of error: It will give rise to a more effective stimulus control of the stimulus more quickly and with considerably less frustration for the student.
3-Maximize the number of tests: The effective control of the stimulus is developed after a person has been reinforced to emit the desired behavior in the presence of E ° in several tests.
4-Make use of the rules: describe contingencies: The development of stimulus control involves the trial and error method, several tests of positive reinforcement of behavior in the presence of an E ° and several tests of that behavior not being reinforced in presence of an E.
Guidelines for effective stimulus discrimination training
Choosing clear signals, selecting an appropriate reinforcement, developing discrimination, realizing that stimulus control over student behavior will not develop if he does not attend to the indexes.