
An operant conditioning chamber (also known as a Skinner box) is a
laboratory apparatus used to study
animal behavior. The operant conditioning chamber was created by
B. F. Skinner while he was a graduate student at
Harvard University
Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...
. The chamber can be used to study both
operant conditioning
Operant conditioning, also called instrumental conditioning, is a learning process in which voluntary behaviors are modified by association with the addition (or removal) of reward or aversive stimuli. The frequency or duration of the behavior ma ...
and
classical conditioning
Classical conditioning (also respondent conditioning and Pavlovian conditioning) is a behavioral procedure in which a biologically potent Stimulus (physiology), stimulus (e.g. food, a puff of air on the eye, a potential rival) is paired with a n ...
.
Skinner created the operant conditioning chamber as a variation of the
puzzle box originally created by
Edward Thorndike
Edward Lee Thorndike ( – ) was an American psychologist who spent nearly his entire career at Teachers College, Columbia University. His work on comparative psychology and the learning process led to his " theory of connectionism" and helped ...
. While Skinner's early studies were done using
rats, he later moved on to study
pigeons.
The operant conditioning chamber may be used to observe or manipulate behaviour. An animal is placed in the box where it must learn to activate levers or respond to light or sound stimuli for
reward. The reward may be food or the removal of
noxious stimuli such as a loud alarm. The chamber is used to test specific
hypotheses
A hypothesis (: hypotheses) is a proposed explanation for a phenomenon. A scientific method, scientific hypothesis must be based on observations and make a testable and reproducible prediction about reality, in a process beginning with an educ ...
in a controlled setting.
Name

Skinner was noted to have expressed his distaste for becoming an
eponym
An eponym is a noun after which or for which someone or something is, or is believed to be, named. Adjectives derived from the word ''eponym'' include ''eponymous'' and ''eponymic''.
Eponyms are commonly used for time periods, places, innovati ...
. It is believed that psychologist
Clark Hull
Clark Leonard Hull (May 24, 1884 – May 10, 1952) was an Americans, American psychologist who sought to explain learning and motivation by scientific laws of behavior. Hull is known for his debates with Edward C. Tolman. He is also known for his ...
and his
Yale students coined the expression "Skinner box". Skinner said that he did not use the term himself; he went so far as to ask
Howard Hunt to use "lever box" instead of "Skinner box" in a published document.
History
In 1898, American psychologist,
Edward Thorndike
Edward Lee Thorndike ( – ) was an American psychologist who spent nearly his entire career at Teachers College, Columbia University. His work on comparative psychology and the learning process led to his " theory of connectionism" and helped ...
proposed the '
law of effect', which formed the basis of operant conditioning. Thorndike conducted experiments to discover how cats learn new behaviors. His work involved monitoring cats as they attempted to escape from puzzle boxes. The puzzle box trapped the animals until they moved a lever or performed an action which triggered their release.
Thorndike ran several trials and recorded the time it took for them to perform the actions necessary to escape. He discovered that the cats seemed to learn from a trial-and-error process rather than insightful inspections of their environment. The animals learned that their actions led to an effect, and the type of effect influenced whether the behavior would be repeated. Thorndike's 'law of effect' contained the core elements of what would become known as
operant conditioning
Operant conditioning, also called instrumental conditioning, is a learning process in which voluntary behaviors are modified by association with the addition (or removal) of reward or aversive stimuli. The frequency or duration of the behavior ma ...
. B. F. Skinner expanded upon Thorndike's existing work.
Skinner theorized that if a behavior is followed by a reward, that behavior is more likely to be repeated, but added that if it is followed by some sort of punishment, it is less likely to be repeated. He introduced the word reinforcement into Thorndike's law of effect.
Through his experiments, Skinner discovered the
law of operant learning which included extinction, punishment and generalization.
Skinner designed the operant conditioning chamber to allow for specific hypothesis testing and behavioural observation. He wanted to create a way to observe animals in a more controlled setting as
observation
Observation in the natural sciences is an act or instance of noticing or perceiving and the acquisition of information from a primary source. In living beings, observation employs the senses. In science, observation can also involve the percep ...
of behaviour in nature can be unpredictable.
Purpose
An operant conditioning chamber allows researchers to study
animal behaviour and response to
conditioning. They do this by teaching an animal to perform certain actions (like pressing a lever) in response to specific stimuli. When the correct action is performed the animal receives positive reinforcement in the form of food or other reward. In some cases, the chamber may deliver
positive punishment to discourage incorrect responses. For example, researchers have tested certain
invertebrate
Invertebrates are animals that neither develop nor retain a vertebral column (commonly known as a ''spine'' or ''backbone''), which evolved from the notochord. It is a paraphyletic grouping including all animals excluding the chordata, chordate s ...
s' reaction to operant conditioning using a "heat box".
The box has two walls used for manipulation; one wall can undergo temperature change while the other cannot. As soon as the invertebrate crosses over to the side which can undergo temperature change, the researcher will increase the temperature. Eventually, the invertebrate will be conditioned to stay on the side that does not undergo a temperature change. After conditioning, even when the temperature is turned to its lowest setting, the invertebrate will avoid that side of the box.
Skinner's pigeon studies involved a series of levers. When the lever was pressed, the pigeon would receive a food reward.
This was made more complex as researchers studied animal learning behaviours. A pigeon would be placed in the conditioning chamber and another one would be placed in an adjacent box separated by a
plexiglass
Poly(methyl methacrylate) (PMMA) is a synthetic polymer derived from methyl methacrylate. It is a transparent thermoplastic, used as an engineering plastic. PMMA is also known as acrylic, acrylic glass, as well as by the trade names and bran ...
wall. The pigeon in the chamber would learn to press the lever to receive food as the other pigeon watched. The pigeons would then be switched, and researchers would observe them for signs of
cultural learning
Cultural learning is the way a group of people or animals within a society or culture tend to learn and pass on information. Learning styles can be greatly influenced by how a culture socializes with its children and young people. Cross-cultural ...
.
Structure

The outside shell of an operant conditioning chamber is a large box big enough to easily accommodate the animal being used as a subject. Commonly used animals include
rodent
Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...
s (usually
lab rats),
pigeon
Columbidae is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with small heads, relatively short necks and slender bills that in some species feature fleshy ceres. ...
s, and
primate
Primates is an order (biology), order of mammals, which is further divided into the Strepsirrhini, strepsirrhines, which include lemurs, galagos, and Lorisidae, lorisids; and the Haplorhini, haplorhines, which include Tarsiiformes, tarsiers a ...
s. The chamber is often
sound-proof and light-proof to avoid distracting stimuli.
Operant conditioning chambers have at least one response mechanism that can automatically detect the occurrence of a
behavior
Behavior (American English) or behaviour (British English) is the range of actions of Individual, individuals, organisms, systems or Artificial intelligence, artificial entities in some environment. These systems can include other systems or or ...
al response or action (i.e.,
pecking, pressing, pushing, etc.). This may be a lever or series of lights which the animal will respond to in the presence of
stimulus. Typical mechanisms for primates and rats are response levers; if the subject presses the lever, the opposite end closes a switch that is monitored by a computer or other programmed device. Typical mechanisms for pigeons and other
bird
Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...
s are
response keys with a switch that closes if the bird pecks at the key with sufficient
force
In physics, a force is an influence that can cause an Physical object, object to change its velocity unless counterbalanced by other forces. In mechanics, force makes ideas like 'pushing' or 'pulling' mathematically precise. Because the Magnitu ...
.
The other minimal requirement of an operant conditioning chamber is that it has a means of delivering a
primary reinforcer such as a food reward.

A simple configuration, such as one response mechanism and one feeder, may be used to investigate a variety of psychological
phenomena
A phenomenon ( phenomena), sometimes spelled phaenomenon, is an observable Event (philosophy), event. The term came into its modern Philosophy, philosophical usage through Immanuel Kant, who contrasted it with the noumenon, which ''cannot'' be ...
. Modern operant conditioning chambers may have multiple mechanisms, such as several response levers, two or more feeders, and a variety of devices capable of generating different
stimuli including lights, sounds, music, figures, and drawings. Some configurations use an
LCD panel for the computer generation of a variety of visual stimuli or a set of
LED lights to create patterns they wish to be replicated.
Some operant conditioning chambers can also have electrified nets or floors so that shocks can be given to the animals as a
positive punishment or lights of different colors that give information about when the food is available as a
positive reinforcement.
Research impact
Operant conditioning chambers have become common in a variety of research disciplines especially in animal learning. The chambers design allows for easy monitoring of the animal and provides a space to manipulate certain behaviours. This controlled environment may allow for research and experimentation which cannot be performed in the field.
There are a variety of applications for operant conditioning. For instance, shaping the behavior of a child is influenced by the compliments, comments, approval, and disapproval of one's behavior. An important factor of operant conditioning is its ability to explain learning in real-life situations. From an early age, parents nurture their children's behavior by using reward and praise following an achievement (crawling or taking a first step) which reinforces such behavior. When a child misbehaves, punishment in the form of verbal discouragement or the removal of privileges are used to discourage them from repeating their actions.
Skinner's studies on animals and their behavior laid the framework needed for similar studies on human subjects. Based on his work, developmental psychologists were able to study the effect of positive and negative
reinforcement. Skinner found that the environment influenced behavior and when that environment is manipulated, behaviour will change. From this, developmental psychologists proposed theories on operant learning in children. That research was applied to education and the treatment of illness in young children.
Skinner's theory of operant conditioning played a key role in helping psychologists understand how behavior is learned. It explains why reinforcement can be used so effectively in the learning process, and how schedules of reinforcement can affect the outcome of conditioning.
Commercial applications
Slot machines,
online games, and dating apps are examples where sophisticated operant schedules of reinforcement are used to reinforce certain behaviors.
Gamification, the technique of using game design elements in non-game contexts, has also been described as using operant conditioning and other behaviorist techniques to encourage desired user behaviors.
See also
*
Behaviorism
Behaviorism is a systematic approach to understand the behavior of humans and other animals. It assumes that behavior is either a reflex elicited by the pairing of certain antecedent stimuli in the environment, or a consequence of that indivi ...
*
Radical behaviorism
Radical behaviorism is a "philosophy of the science of behavior" developed by B. F. Skinner. It refers to the philosophy behind behavior analysis, and is to be distinguished from methodological behaviorism—which has an intense emphasis ...
*
Operant conditioning
Operant conditioning, also called instrumental conditioning, is a learning process in which voluntary behaviors are modified by association with the addition (or removal) of reward or aversive stimuli. The frequency or duration of the behavior ma ...
*
Punishment (psychology)
*
Reinforcement
*
Synchronicity
References
{{Reflist
External links
B.F. Skinner Foundation
Laboratory equipment
Behaviorism
Behavioral neuroscience
Learning
Animal testing techniques