Classical conditioning in the context of Experiment

Learning is the process of acquiring new understanding, knowledge, behaviors, skills, values, attitudes, and preferences. The ability to learn is possessed by humans, non-human animals, and some machines; there is also evidence for some kind of learning in certain plants. Some learning is immediate, induced by a single event (e.g. being burned by a hot stove), but much skill and knowledge accumulate from repeated experiences. The changes induced by learning often last a lifetime, and it is hard to distinguish learned material that seems to be "lost" from that which cannot be retrieved.

Human learning starts at birth (it might even start before) and continues until death as a consequence of ongoing interactions between people and their environment. The nature and processes involved in learning are studied in many established fields (including educational psychology, neuropsychology, experimental psychology, cognitive sciences, and pedagogy), as well as emerging fields of knowledge (e.g. with a shared interest in the topic of learning from safety events such as incidents/accidents, or in collaborative learning health systems). Research in such fields has led to the identification of various sorts of learning. For example, learning may occur as a result of habituation, or classical conditioning, operant conditioning or as a result of more complex activities such as play, seen only in relatively intelligent animals. Learning may occur consciously or without conscious awareness. Learning that an aversive event cannot be avoided or escaped may result in a condition called learned helplessness. There is evidence for human behavioral learning prenatally, in which habituation has been observed as early as 32 weeks into gestation, indicating that the central nervous system is sufficiently developed and primed for learning and memory to occur very early on in development.

Brave New World is a dystopian novel by English author Aldous Huxley, written in 1931, and published in 1932. Largely set in a futuristic World State, whose citizens are environmentally engineered into an intelligence-based social hierarchy, the novel anticipates huge scientific advancements in reproductive technology, sleep-learning, psychological manipulation and classical conditioning that are combined to make a dystopian society which is challenged by the story's protagonist. Huxley followed this book with a reassessment in essay form, Brave New World Revisited (1958), and with his final novel, Island (1962), the utopian counterpart. This novel is often used as a companion piece, or inversion counterpart to George Orwell's Nineteen Eighty-Four (1949).

In 1998 and 1999, the Modern Library ranked Brave New World at number 5 on its list of the 100 Best Novels in English of the 20th century. In 2003, Robert McCrum, writing for The Observer, included Brave New World chronologically at number 53 in "the top 100 greatest novels of all time", and the novel was listed at number 87 on The Big Read survey by the BBC. Brave New World has frequently been banned and challenged since its original publication. It has landed on the American Library Association list of top 100 banned and challenged books of the decade since the association began the list in 1990.

In psychology, a stimulus is any object or event that elicits a sensory or behavioral response in an organism. In this context, a distinction is made between the distal stimulus (the external, perceived object) and the proximal stimulus (the stimulation of sensory organs).

• In perceptual psychology, a stimulus is an energy change (e.g., light or sound) which is registered by the senses (e.g., vision, hearing, taste, etc.) and constitutes the basis for perception.
• In behavioral psychology (i.e., classical and operant conditioning), a stimulus constitutes the basis for behavior. The stimulus–response model emphasizes the relation between stimulus and behavior rather than an animal's internal processes (i.e., in the nervous system).
• In experimental psychology, a stimulus is the event or object to which a response is measured. Thus, not everything that is presented to participants qualifies as stimulus. For example, a cross mark at the center of a screen is not said to be a stimulus, because it merely serves to center participants' gaze on the screen. Also, it is uncommon to refer to longer events (e.g. the Trier social stress test) as a stimulus, even if a response to such an event is measured.

Ivan Petrovich Pavlov (Russian: Иван Петрович Павлов, IPA: [ɪˈvan pʲɪˈtrovʲɪtɕ ˈpavləf] ; 26 September [O.S. 14 September] 1849 – 27 February 1936) was a Russian and Soviet experimental neurologist and physiologist known for his discovery of classical conditioning through his experiments with dogs. Pavlov also conducted significant research on the physiology of digestion, for which he was awarded the Nobel Prize in Physiology or Medicine in 1904.

Extinction in psychology refers to the gradual decrease and possible elimination of a learned behavior. This behavioral phenomenon can be observed in both operantly conditioned and classically conditioned behavior. When operant behavior that has been previously reinforced no longer produces reinforcing consequences, the behavior gradually returns to operant levels (to the frequency of the behavior previous to learning, which may or may not be zero).

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.

In behavioral psychology, stimulus control is a phenomenon in operant conditioning that occurs when an organism behaves in one way in the presence of a given stimulus and another way in its absence. A stimulus that modifies behavior in this manner is either a discriminative stimulus or stimulus delta. For example, the presence of a stop sign at a traffic intersection alerts the driver to stop driving and increases the probability that braking behavior occurs. Stimulus control does not force behavior to occur, as it is a direct result of historical reinforcement contingencies, as opposed to reflexive behavior elicited through classical conditioning.

Some theorists believe that all behavior is under some form of stimulus control. For example, in the analysis of B. F. Skinner, verbal behavior is a complicated assortment of behaviors with a variety of controlling stimuli.

Psychology is defined as "the scientific study of behavior and mental processes". Philosophical interest in the human mind and behavior dates back to the ancient civilizations of Egypt, Persia, Greece, China, and India.

Psychology as a field of experimental study began in 1854 in Leipzig, Germany, when Gustav Fechner created the first theory of how judgments about sensory experiences are made and how to experiment on them. Fechner's theory, recognized today as Signal Detection Theory, foreshadowed the development of statistical theories of comparative judgment and thousands of experiments based on his ideas (Link, S. W. Psychological Science, 1995). In 1879, Wilhelm Wundt founded the first psychological laboratory dedicated exclusively to psychological research in Leipzig, Germany. Wundt was also the first person to refer to himself as a psychologist. A notable precursor to Wundt was Ferdinand Ueberwasser (1752–1812), who designated himself Professor of Empirical Psychology and Logic in 1783 and gave lectures on empirical psychology at the Old University of Münster, Germany. Other important early contributors to the field include Hermann Ebbinghaus (a pioneer in the study of memory), William James (the American father of pragmatism), and Ivan Pavlov (who developed the procedures associated with classical conditioning).

The reward system (the mesocorticolimbic circuit) is a group of neural structures responsible for incentive salience (i.e., "wanting"; desire or craving for a reward and motivation), associative learning (primarily positive reinforcement and classical conditioning), and positively-valenced emotions, particularly ones involving pleasure as a core component (e.g., joy, euphoria and ecstasy). Reward is the attractive and motivational property of a stimulus that induces appetitive behavior, also known as approach behavior, and consummatory behavior. A rewarding stimulus has been described as "any stimulus, object, event, activity, or situation that has the potential to make us approach and consume it is by definition a reward". In operant conditioning, rewarding stimuli function as positive reinforcers; however, the converse statement also holds true: positive reinforcers are rewarding. The reward system motivates animals to approach stimuli or engage in behaviour that increases fitness (sex, energy-dense foods, etc.). Survival for most animal species depends upon maximizing contact with beneficial stimuli and minimizing contact with harmful stimuli. Reward cognition serves to increase the likelihood of survival and reproduction by causing associative learning, eliciting approach and consummatory behavior, and triggering positively-valenced emotions. Thus, reward is a mechanism that evolved to help increase the adaptive fitness of animals. In drug addiction, certain substances over-activate the reward circuit, leading to compulsive substance-seeking behavior resulting from synaptic plasticity in the circuit.

Primary rewards are a class of rewarding stimuli which facilitate the survival of one's self and offspring, and they include homeostatic (e.g., palatable food) and reproductive (e.g., sexual contact and parental investment) rewards. Intrinsic rewards are unconditioned rewards that are attractive and motivate behavior because they are inherently pleasurable. Extrinsic rewards (e.g., money or seeing one's favorite sports team winning a game) are conditioned rewards that are attractive and motivate behavior but are not inherently pleasurable. Extrinsic rewards derive their motivational value as a result of a learned association (i.e., conditioning) with intrinsic rewards. Extrinsic rewards may also elicit pleasure (e.g., euphoria from winning a lot of money in a lottery) after being classically conditioned with intrinsic rewards.

Activity theory (AT; Russian: Теория деятельности) is an umbrella term for a line of eclectic social-sciences theories and research with its roots in the Soviet psychological activity theory pioneered by Sergei Rubinstein in the 1930s. It was later advocated for and popularized by Alexei Leont'ev. Some of the traces of the theory in its inception can also be found in a few works of Lev Vygotsky. These scholars sought to understand human activities as systemic and socially situated phenomena and to go beyond paradigms of reflexology (the teaching of Vladimir Bekhterev and his followers) and classical conditioning (the teaching of Ivan Pavlov and his school), psychoanalysis and behaviorism. It became one of the major psychological approaches in the former USSR, being widely used in both theoretical and applied psychology, and in education, professional training, ergonomics, social psychology and work psychology.

Activity theory is more of a descriptive meta-theory or framework than a predictive theory. It considers an entire work/activity system (including teams, organizations, etc.) beyond just one actor or user. It accounts for environment, history of the person, culture, role of the artifact, motivations, and complexity of real-life activity. One of the strengths of AT is that it bridges the gap between the individual subject and the social reality—it studies both through the mediating activity. The unit of analysis in AT is the concept of object-oriented, collective and culturally mediated human activity, or activity system. This system includes the object (or objective), subject, mediating artifacts (signs and tools), rules, community and division of labor. The motive for the activity in AT is created through the tensions and contradictions within the elements of the system. According to ethnographer Bonnie Nardi, a leading theorist in AT, activity theory "focuses on practice, which obviates the need to distinguish 'applied' from 'pure' science—understanding everyday practice in the real world is the very objective of scientific practice. ... The object of activity theory is to understand the unity of consciousness and activity." Sometimes called "Cultural-Historical Activity Theory", this approach is particularly useful for studying a group that exists "largely in virtual form, its communications mediated largely through electronic and printed texts." Cultural-Historical Activity Theory has accordingly also been applied to genre theory within writing studies to consider how quasi-stabilized forms of communication regularize relations and work while forming communally shared knowledge and values in both educational and workplace settings.

Domain specificity is a theoretical position in cognitive science (especially modern cognitive development) that argues that many aspects of cognition are supported by specialized, presumably evolutionarily specified, learning devices. The position is a close relative of modularity of mind, but is considered more general in that it does not necessarily entail all the assumptions of Fodorian modularity (e.g., informational encapsulation). Instead, it is properly described as a variant of psychological nativism. Other cognitive scientists also hold the mind to be modular, without the modules necessarily possessing the characteristics of Fodorian modularity.

Domain specificity emerged in the aftermath of the cognitive revolution as a theoretical alternative to empiricist theories that believed all learning can be driven by the operation of a few such general learning devices. Prominent examples of such domain-general views include Jean Piaget's theory of cognitive development, and the views of many modern connectionists. Proponents of domain specificity argue that domain-general learning mechanisms are unable to overcome the epistemological problems facing learners in many domains, especially language. In addition, domain-specific accounts draw support from the surprising competencies of infants, who are able to reason about things like numerosity, goal-directed behavior, and the physical properties of objects all in the first months of life. Domain-specific theorists argue that these competencies are too sophisticated to have been learned via a domain-general process like associative learning, especially over such a short time and in the face of the infant's perceptual, attentional, and motor deficits. Current proponents of domain specificity argue that evolution equipped humans (and indeed most other species) with specific adaptations designed to overcome persistent problems in the environment. For humans, popular candidates include reasoning about objects, other intentional agents, language, and number. Researchers in this field seek evidence for domain specificity in a variety of ways. Some look for unique cognitive signatures thought to characterize a domain (e.g. differences in ways infants reason about inanimate versus animate entities). Others try to show selective impairment or competence within but not across domains (e.g. the increased ease of solving the Wason Selection Task when the content is social in nature). Still, others use learnability arguments to argue that a cognitive process or specific cognitive content could not be learned, as in Noam Chomsky's poverty of the stimulus argument for language.

Bee learning and communication includes cognitive and sensory processes in all kinds of bees, that is the insects in the seven families making up the clade Anthophila. Some species have been studied more extensively than others, in particular Apis mellifera, or European honey bee. Color learning has also been studied in bumblebees.

Honey bees are sensitive to odors (including pheromones), tastes, and colors, including ultraviolet. They can demonstrate capabilities such as color discrimination through classical and operant conditioning and retain this information for several days at least; they communicate the location and nature of sources of food; they adjust their foraging to the times at which food is available; they may even form cognitive maps of their surroundings. They also communicate with each other by means of a "waggle dance" and in other ways.

Equine intelligence, long described in myths and anecdotes, has been the subject of scientific study since the early 20th century. The worldwide fascination for clever horses, such as Clever Hans, gave rise to a long-running controversy over the cognitive abilities of horses. The discovery of the Clever Hans effect, followed by the development of ethological studies, has progressively revealed a high level of social intelligence evident in horse's behavior. The scientific discipline that studies equine cognition, at the crossroads of ethology and animal psychology, is cognitive ethology.

Although the existence of consciousness among horses is yet to be proven, their remarkable memory has been recognized for centuries. Because of their wild herd lifestyle, horses also exhibit advanced cognitive abilities related to the theory of mind, enabling them to understand interactions with other individuals. They can recognize a human by their facial features, communicate with them through body language, and learn new skills by observing a person's behavior. Horses are also adept at categorizing and conceptual learning. In terms of working intelligence, horses respond well to habituation, desensitization, classical conditioning, and operant conditioning. They can also improvise and adapt to suit their rider. Understanding how horses' cognitive abilities function has practical applications in the relationship between domesticated horses and humans, particularly in areas such as training, breeding, and day-to-day management, which can ultimately improve their well-being.

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. The chamber can be used to study both operant conditioning and classical conditioning.

Skinner created the operant conditioning chamber as a variation of the puzzle box originally created by Edward Thorndike. 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 in a controlled setting.

Clark Leonard Hull (May 24, 1884 – May 10, 1952) was an 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 work in drive theory.

Hull spent the mature part of his career at Yale University, where he was recruited by the president and former psychologist, James Rowland Angell. He performed research demonstrating that his theories could predict behavior. His most significant works were the Mathematico-Deductive Theory of Rote Learning (1940), and Principles of Behavior (1943), which established his analysis of animal learning and conditioning as the dominant learning theory of its time. Hull's model is expressed in biological terms: Organisms suffer deprivation; deprivation creates needs; needs activate drives; drives activate behavior; behavior is goal directed; achieving the goal has survival value.