Our surroundings constantly shape our actions, influencing how organisms learn and adapt. Stimulus control describes how an organism learns to respond to particular environmental cues, but not others, based on past experiences. This phenomenon is a widespread influence on behavior in everyday life.
Defining Stimulus Control
Stimulus control occurs when a behavior becomes more probable in the presence of a specific stimulus than in its absence. This cue is known as a discriminative stimulus, or SD. Conversely, when the behavior is less likely to occur, or is suppressed, in the presence of another stimulus, that cue is called an S-delta. An organism learns to differentiate between these stimuli, responding appropriately to one and not the other. This discrimination results from a history where responding to the SD led to reinforcement, while responding to the S-delta did not, or even led to punishment.
Mechanisms of Stimulus Influence
The process by which stimuli gain control over behavior involves consistent pairings of a stimulus, a behavior, and a consequence. An SD signals that a specific behavior will likely be followed by a reinforcing outcome. For example, a dog learns to sit only when a specific hand signal is given, because that signal reliably precedes a treat for sitting. The hand signal thus becomes an SD for sitting.
An S-delta signals that a behavior will not be reinforced or may lead to an undesirable outcome. If the dog sits without the specific hand signal, it does not receive a treat, making the absence of the signal an S-delta for sitting. Through repeated experiences, the organism learns to adjust its behavior based on these environmental signals, demonstrating refined control by external cues. This learning process allows for efficient and appropriate responses in varied situations.
The Practical Importance of Stimulus Control
Stimulus control makes behavior predictable, efficient, and adaptable, demonstrating its widespread value across many domains. In educational settings, classroom cues consistently guide student conduct. For instance, the sound of a school bell signals the end of recess, prompting students to transition back to their classrooms, or a teacher’s raised hand cues students to quiet down and pay attention. These environmental signals help maintain an organized learning environment.
Animal training heavily relies on establishing stimulus control to elicit desired behaviors from pets. A specific verbal command like “stay” or a particular hand signal becomes an SD for the animal to remain in place, because following the command has consistently led to rewards. This precise control allows for complex behaviors to be taught and maintained.
In therapeutic contexts, understanding stimulus control assists in modifying behaviors. Therapists might help individuals identify environmental cues that trigger undesirable habits, then work to remove or alter those cues to reduce the behavior. For example, removing tempting food items from plain sight can reduce spontaneous overeating, as the visual cue for eating is no longer present.
Our daily routines are also heavily influenced by stimulus control. The sound of an alarm clock serves as an SD for waking up and beginning the day’s activities, while the sight of a coffee maker might trigger the habit of brewing coffee. These everyday environmental triggers guide our actions, making many routine behaviors automatic and efficient.