Classical conditioning in the context of "Learning"

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).