Stimulus control
Encyclopedia
Stimulus control is the phenomenon of a stimulus increasing the probability of a behavior (operant response) because of a history of that behavior being differentially reinforced in the presence of the stimulus. In other words, stimulus control is basically learning to pay attention to things that we identify in the environment (discriminative stimuli) that give us information about the effectiveness of our behavior: what behavior is likely to be effective or ineffective, under which conditions, and what the behavior gives us (reinforcement
or punishment
). Therefore, in the presence of those stimuli we are likely to respond differentially.
Imagine the following experiment. A pigeon is trained to peck an unlit left key in order to obtain food (reinforcer). After the animal learns this simple task, a right key is lit. Because the right key gives little information to the pigeon, after some time it is ignored. But what would happen if we changed the procedure, turning the light on and off, and giving food to the pigeon only when it pecks the left key when the right key is lit? Under these conditions, the pigeon starts to peck the left key when the right key is lit, and not when it is dark. Thus, we can say that the pigeon starts to respond differently in the presence of these two stimuli (right key lit or dark). That is, the discriminative stimulus is controlling the pigeon’s behavior. In this context, control does not mean that the pigeon has no choice; it only refers to the probability of responding in the presence of the discriminative stimulus (lit right key).
The opposite of discrimination, in which a subject learns to respond to one stimulus and not to another stimulus (e.g. the pigeon responds when the right key is lit and not when it is dark), is generalization. After behaving in a certain way in the presence of one stimulus, animals tend to behave similarly in the presence of a similar stimulus. That is, their behavior generalizes from one stimulus to another. For example, what would a pigeon do if, after being exposed to the procedure described above (i.e., after it learned to peck a left key only when a right key is lit), the intensity or wavelength of the light is changed? One way to try to answer to this question would be presenting five variations of the lit right key, each one presented for a relative brief period (e.g. 5 seconds), and measure the number of responses to the left key to each of the five color variations. The universal result – with pigeons, rats, fungi, monkeys, goldfish and people – is that response is highest to the original training stimulus (in this experiment, the initial key lighting plan), and decreases systematically as the physical difference between the training and the test stimuli increases.
In the quantitative analysis of behavior
, stimulus control is examined from a number of perspectives, including Matching to Sample, and signal detection
(Nevin
, 1965; 1969).
Reinforcement
Reinforcement is a term in operant conditioning and behavior analysis for the process of increasing the rate or probability of a behavior in the form of a "response" by the delivery or emergence of a stimulus Reinforcement is a term in operant conditioning and behavior analysis for the process of...
or punishment
Punishment (psychology)
In operant conditioning, punishment is any change in a human or animal's surroundings that occurs after a given behavior or response which reduces the likelihood of that behavior occurring again in the future. As with reinforcement, it is the behavior, not the animal, that is punished...
). Therefore, in the presence of those stimuli we are likely to respond differentially.
Imagine the following experiment. A pigeon is trained to peck an unlit left key in order to obtain food (reinforcer). After the animal learns this simple task, a right key is lit. Because the right key gives little information to the pigeon, after some time it is ignored. But what would happen if we changed the procedure, turning the light on and off, and giving food to the pigeon only when it pecks the left key when the right key is lit? Under these conditions, the pigeon starts to peck the left key when the right key is lit, and not when it is dark. Thus, we can say that the pigeon starts to respond differently in the presence of these two stimuli (right key lit or dark). That is, the discriminative stimulus is controlling the pigeon’s behavior. In this context, control does not mean that the pigeon has no choice; it only refers to the probability of responding in the presence of the discriminative stimulus (lit right key).
The opposite of discrimination, in which a subject learns to respond to one stimulus and not to another stimulus (e.g. the pigeon responds when the right key is lit and not when it is dark), is generalization. After behaving in a certain way in the presence of one stimulus, animals tend to behave similarly in the presence of a similar stimulus. That is, their behavior generalizes from one stimulus to another. For example, what would a pigeon do if, after being exposed to the procedure described above (i.e., after it learned to peck a left key only when a right key is lit), the intensity or wavelength of the light is changed? One way to try to answer to this question would be presenting five variations of the lit right key, each one presented for a relative brief period (e.g. 5 seconds), and measure the number of responses to the left key to each of the five color variations. The universal result – with pigeons, rats, fungi, monkeys, goldfish and people – is that response is highest to the original training stimulus (in this experiment, the initial key lighting plan), and decreases systematically as the physical difference between the training and the test stimuli increases.
In the quantitative analysis of behavior
Quantitative Analysis of Behavior
Quantitative analysis of behavior is the quantitative form of the experimental analysis of behavior. This has become the dominant scientific approach to behavior analysis. It represents behavioral research using quantitative models of behavior. The parameters in the models hopefully have...
, stimulus control is examined from a number of perspectives, including Matching to Sample, and signal detection
Detection theory
Detection theory, or signal detection theory, is a means to quantify the ability to discern between information-bearing energy patterns and random energy patterns that distract from the information Detection theory, or signal detection theory, is a means to quantify the ability to discern between...
(Nevin
John Anthony Nevin
John Anthony Nevin is Professor Emeritus of Psychology, University of New Hampshire. He was born July 5, 1933, in New York City. In 1954, he obtained a B.E. in Mechanical Engineering from Yale University, in 1961 an M.A. at Columbia University, then in 1963 a Ph.D. in Psychology. William N....
, 1965; 1969).
Matching to sample
Matching-to-Sample is a form of conditional discrimination. In this form of conditional discrimination procedure, only one of two or more stimuli presented on other comparison keys from the sample, shares some property (e.g., shape). Responses to the similar stimulus are reinforced. In Oddity matching, a form of matching-to-sample, responses to the comparison stimulus that does not match the sample are reinforced.Characteristics
Proper stimulus control is said to have four characteristics:- The behavior occurs immediately when the conditioned stimulus is given.
- The behavior never occurs in the absence of the stimulus.
- The behavior never occurs in response to some other stimulus.
- No other behavior occurs in response to this stimulus.
See also
- Behavior therapy
- BehaviorismBehaviorismBehaviorism , also called the learning perspective , is a philosophy of psychology based on the proposition that all things that organisms do—including acting, thinking, and feeling—can and should be regarded as behaviors, and that psychological disorders are best treated by altering behavior...
- Signal detectionDetection theoryDetection theory, or signal detection theory, is a means to quantify the ability to discern between information-bearing energy patterns and random energy patterns that distract from the information Detection theory, or signal detection theory, is a means to quantify the ability to discern between...
- Quantitative analysis of behaviorQuantitative Analysis of BehaviorQuantitative analysis of behavior is the quantitative form of the experimental analysis of behavior. This has become the dominant scientific approach to behavior analysis. It represents behavioral research using quantitative models of behavior. The parameters in the models hopefully have...
- Motivating operationMotivating operationMotivating operations or establishing operations, are a concept in behaviorism involving the effectiveness of consequences in operant conditioning. They explain why a person wants or does not want something and why they act or do not act in a particular moment....