Burrhus Frederic Skinner was an American psychologist, behaviorist, author, inventor, and social philosopher. He was a professor of psychology at Harvard University from 1958 until his retirement in 1974.
Operant conditioning is a type of associative learning process through which the strength of a behavior is modified by reinforcement or punishment. It is also a procedure that is used to bring about such learning.
Classical conditioning refers to a learning procedure in which a biologically potent stimulus is paired with a previously neutral stimulus. It also refers to the learning process that results from this pairing, through which the neutral stimulus comes to elicit a response that is usually similar to the one elicited by the potent stimulus.
In behavioral psychology, reinforcement is a consequence applied that will strengthen an organism's future behavior whenever that behavior is preceded by a specific antecedent stimulus. This strengthening effect may be measured as a higher frequency of behavior, longer duration, greater magnitude, or shorter latency. There are two types of reinforcement, known as positive reinforcement and negative reinforcement; positive is whereby a reward is offered on expression of the wanted behaviour and negative is taking away an undesirable element in the persons environment whenever the desired behaviour is achieved. Rewarding stimuli, which are associated with "wanting" and "liking" and appetitive behavior, function as positive reinforcers; the converse statement is also true: positive reinforcers provide a desirable stimulus. Reinforcement does not require an individual to consciously perceive an effect elicited by the stimulus. Thus, reinforcement occurs only if there is an observable strengthening in behavior. However, there is also negative reinforcement, which is characterized by taking away an undesirable stimulus. Changing someone's job might serve as a negative reinforcer to someone who suffers from back problems, i.e. Changing from a labourers job to an office position for instance.
The experimental analysis of behavior is school of thought in psychology founded on B. F. Skinner's philosophy of radical behaviorism and defines the basic principles used in applied behavior analysis. A central principle was the inductive reasoning data-driven examination of functional relations, as opposed to the kinds of hypothetico-deductive learning theory that had grown up in the comparative psychology of the 1920–1950 period. Skinner's approach was characterized by observation of measurable behavior which could be predicted and controlled. It owed its early success to the effectiveness of Skinner's procedures of operant conditioning, both in the laboratory and in behavior therapy.
The Little Albert experiment was a controlled experiment showing empirical evidence of classical conditioning in humans. The study also provides an example of stimulus generalization. It was carried out by John B. Watson and his graduate student, Rosalie Rayner, at Johns Hopkins University. The results were first published in the February 1920 issue of the Journal of Experimental Psychology.
The Rescorla–Wagner model ("R-W") is a model of classical conditioning, in which learning is conceptualized in terms of associations between conditioned (CS) and unconditioned (US) stimuli. A strong CS-US association means, essentially, that the CS signals or predicts the US. One might say that before conditioning, the subject is surprised by the US, but after conditioning, the subject is no longer surprised, because the CS predicts the coming of the US. The model casts the conditioning processes into discrete trials, during which stimuli may be either present or absent. The strength of prediction of the US on a trial can be represented as the summed associative strengths of all CSs present during the trial. This feature of the model represented a major advance over previous models, and it allowed a straightforward explanation of important experimental phenomena, most notably the blocking effect. Failures of the model have led to modifications, alternative models, and many additional findings. The model has had some impact on neural science in recent years, as studies have suggested that the phasic activity of dopamine neurons in mesostriatal DA projections in the midbrain encodes for the type of prediction error detailed in the model.
Shaping is a conditioning paradigm used primarily in the experimental analysis of behavior. The method used is differential reinforcement of successive approximations. It was introduced by B. F. Skinner with pigeons and extended to dogs, dolphins, humans and other species. In shaping, the form of an existing response is gradually changed across successive trials towards a desired target behavior by reinforcing exact segments of behavior. Skinner's explanation of shaping was this:
We first give the bird food when it turns slightly in the direction of the spot from any part of the cage. This increases the frequency of such behavior. We then withhold reinforcement until a slight movement is made toward the spot. This again alters the general distribution of behavior without producing a new unit. We continue by reinforcing positions successively closer to the spot, then by reinforcing only when the head is moved slightly forward, and finally only when the beak actually makes contact with the spot. ... The original probability of the response in its final form is very low; in some cases it may even be zero. In this way we can build complicated operants which would never appear in the repertoire of the organism otherwise. By reinforcing a series of successive approximations, we bring a rare response to a very high probability in a short time. ... The total act of turning toward the spot from any point in the box, walking toward it, raising the head, and striking the spot may seem to be a functionally coherent unit of behavior; but it is constructed by a continual process of differential reinforcement from undifferentiated behavior, just as the sculptor shapes his figure from a lump of clay.
Extinction is a behavioral phenomenon observed in both operantly conditioned and classically conditioned behavior, which manifests itself by fading of non-reinforced conditioned response over time. When operant behavior that has been previously reinforced no longer produces reinforcing consequences the behavior gradually stops occurring. In classical conditioning, when a conditioned stimulus is presented alone, so that it no longer predicts the coming of the unconditioned stimulus, conditioned responding gradually stops. For example, after Pavlov's dog was conditioned to salivate at the sound of a metronome, it eventually stopped salivating to the metronome after the metronome had been sounded repeatedly but no food came. Many anxiety disorders such as post traumatic stress disorder are believed to reflect, at least in part, a failure to extinguish conditioned fear.
An avoidance response is a natural adaptive behavior performed in response to danger. Excessive avoidance has been suggested to contribute to anxiety disorders, leading psychologists and neuroscientists to study how avoidance behaviors are learned using rat or mouse models. Avoidance learning is a type of operant conditioning.
In operant conditioning, punishment is any change in a human or animal's surroundings which, occurring after a given behavior or response, reduces the likelihood of that behavior occurring again in the future. As with reinforcement, it is the behavior, not the human/animal, that is punished. Whether a change is or is not punishing is determined by its effect on the rate that the behavior occurs, not by any "hostile" or aversive features of the change. For example, a painful stimulus which would act as a punisher for most people may actually reinforce some behaviors of masochistic individuals.
William Kaye Estes was an American psychologist. A Review of General Psychology survey, published in 2002, ranked Estes as the 77th most cited psychologist of the 20th century. In order to develop a statistical explanation for the learning phenomena, William Kaye Estes developed the Stimulus Sampling Theory in 1950 which suggested that a stimulus-response association is learned on a single trial; however, the learning process is continuous and consists of the accumulation of distinct stimulus-response pairings.
Joseph Vincent Brady was an American psychologist, neuroscientist, and pioneer of behavioral pharmacology. In addition to his status as a founder of behavioral pharmacology, he made significant contributions in the areas of drug abuse and treatment, space exploration, and human research ethics.
The basolateral amygdala (BLA), or basolateral complex, consists of the lateral, basal and accessory-basal nuclei of the amygdala. The lateral nuclei receives the majority of sensory information, which arrives directly from the temporal lobe structures, including the hippocampus and primary auditory cortex. The information is then processed by the basolateral complex and is sent as output to the central nucleus of the amygdala. This is how most emotional arousal is formed in mammals.
In psychology, a stimulus is any object or event that elicits a sensory or behavioral response in an organism.
Sensory preconditioning is an extension of classical conditioning. Procedurally, sensory preconditioning involves repeated simultaneous presentations (pairing) of two neutral stimuli, i.e. stimuli that are not associated with a desired unconditioned response.
The term conditioned emotional response (CER) can refer to a specific learned behavior or a procedure commonly used in classical or Pavlovian conditioning research. It may also be called "conditioned suppression" or "conditioned fear response (CFR)." It is an "emotional response" that results from classical conditioning, usually from the association of a relatively neutral stimulus with a painful or fear-inducing unconditional stimulus. As a result, the formerly neutral stimulus elicits fear. For example, if seeing a dog is paired with the pain of being bitten by the dog, seeing a dog may become a conditioned stimulus that elicits fear.
External inhibition is the observed decrease of the response of a conditioned reaction when an external (distracting) stimulus that was not part of the original conditioned response set is introduced. This effect was first observed in Ivan Pavlov's classical conditioning studies where the dogs would salivate less when presented with the sound of the tuning fork in the distracting context of a passing truck. External inhibition is important for its main principle in classical conditioning where a conditioned response may decrease in magnitude after the external stimulus is introduced. This is especially advantageous for when trying to disassociate conditioned stimulus and responses. A practical example is where students who become anxious upon standing in front of the class to give a presentation may feel less anxiety if their friends were sitting in front of the student presenting. The positive association of speaking to friends may distract the student from associating speaking to the entire class with anxiety.
Pavlovian-instrumental transfer (PIT) is a psychological phenomenon that occurs when a conditioned stimulus that has been associated with rewarding or aversive stimuli via classical conditioning alters motivational salience and operant behavior. Two distinct forms of Pavlovian-instrumental transfer have been identified in humans and other animals – specific PIT and general PIT – with unique neural substrates mediating each type. In relation to rewarding stimuli, specific PIT occurs when a CS is associated with a specific rewarding stimulus through classical conditioning and subsequent exposure to the CS enhances an operant response that is directed toward the same reward with which it was paired. General PIT occurs when a CS is paired with one reward and it enhances an operant response that is directed toward a different rewarding stimulus.
Association in psychology refers to a mental connection between concepts, events, or mental states that usually stems from specific experiences. Associations are seen throughout several schools of thought in psychology including behaviorism, associationism, psychoanalysis, social psychology, and structuralism. The idea stems from Plato and Aristotle, especially with regard to the succession of memories, and it was carried on by philosophers such as John Locke, David Hume, David Hartley, and James Mill. It finds its place in modern psychology in such areas as memory, learning, and the study of neural pathways.
