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Tuesday, December 6, 2022

Behaviorism

From Wikipedia, the free encyclopedia

Behaviorism is a systematic approach to understanding the behavior of humans and animals. It assumes that behavior is either a reflex evoked by the pairing of certain antecedent stimuli in the environment, or a consequence of that individual's history, including especially reinforcement and punishment contingencies, together with the individual's current motivational state and controlling stimuli. Although behaviorists generally accept the important role of heredity in determining behavior, they focus primarily on environmental events.

Behaviorism emerged in the early 1900s as a reaction to depth psychology and other traditional forms of psychology, which often had difficulty making predictions that could be tested experimentally, but derived from earlier research in the late nineteenth century, such as when Edward Thorndike pioneered the law of effect, a procedure that involved the use of consequences to strengthen or weaken behavior.

With a 1924 publication, John B. Watson devised methodological behaviorism, which rejected introspective methods and sought to understand behavior by only measuring observable behaviors and events. It was not until the 1930s that B. F. Skinner suggested that covert behavior—including cognition and emotions—is subject to the same controlling variables as observable behavior, which became the basis for his philosophy called radical behaviorism. While Watson and Ivan Pavlov investigated how (conditioned) neutral stimuli elicit reflexes in respondent conditioning, Skinner assessed the reinforcement histories of the discriminative (antecedent) stimuli that emits behavior; the technique became known as operant conditioning.

The application of radical behaviorism—known as applied behavior analysis—is used in a variety of contexts, including, for example, applied animal behavior and organizational behavior management to treatment of mental disorders, such as autism and substance abuse. In addition, while behaviorism and cognitive schools of psychological thought do not agree theoretically, they have complemented each other in the cognitive-behavior therapies, which have demonstrated utility in treating certain pathologies, including simple phobias, PTSD, and mood disorders.

Branches Of Behaviorisms

The titles given to the various branches of behaviorism include:

  • Behavioral genetics: Proposed in 1869 by Francis Galton, a relative of Charles Darwin.
  • Interbehaviorism: Proposed by Jacob Robert Kantor before B. F. Skinner's writings.
  • Methodological behaviorism: John B. Watson's behaviorism states that only public events (motor behaviors of an individual) can be objectively observed. Although it was still acknowledged that thoughts and feelings exist, they were not considered part of the science of behavior. It also laid the theoretical foundation for the early approach behavior modification in the 1970s and 1980s.
  • Psychological behaviorism: As proposed by Arthur W. Staats, unlike the previous behaviorisms of Skinner, Hull, and Tolman, was based upon a program of human research involving various types of human behavior. Psychological behaviorism introduces new principles of human learning. Humans learn not only by animal learning principles but also by special human learning principles. Those principles involve humans' uniquely huge learning ability. Humans learn repertoires that enable them to learn other things. Human learning is thus cumulative. No other animal demonstrates that ability, making the human species unique.
  • Radical behaviorism: Skinner's philosophy is an extension of Watson's form of behaviorism by theorizing that processes within the organism—particularly, private events, such as thoughts and feelings—are also part of the science of behavior, and suggests that environmental variables control these internal events just as they control observable behaviors. Although private events cannot be directly seen by others, they are later determined through the species' overt behavior. Radical behaviorism forms the core philosophy behind behavior analysis. Willard Van Orman Quine used many of radical behaviorism's ideas in his study of knowledge and language.
  • Teleological behaviorism: Proposed by Howard Rachlin, post-Skinnerian, purposive, close to microeconomics. Focuses on objective observation as opposed to cognitive processes.
  • Theoretical behaviorism: Proposed by J. E. R. Staddon, adds a concept of internal state to allow for the effects of context. According to theoretical behaviorism, a state is a set of equivalent histories, i.e., past histories in which members of the same stimulus class produce members of the same response class (i.e., B. F. Skinner's concept of the operant). Conditioned stimuli are thus seen to control neither stimulus nor response but state. Theoretical behaviorism is a logical extension of Skinner's class-based (generic) definition of the operant.

Two subtypes of theoretical behaviorism are:

  • Hullian and post-Hullian: theoretical, group data, not dynamic, physiological
  • Purposive: Tolman's behavioristic anticipation of cognitive psychology

Modern-day theory: radical behaviorism

B. F. Skinner proposed radical behaviorism as the conceptual underpinning of the experimental analysis of behavior. This viewpoint differs from other approaches to behavioral research in various ways, but, most notably here, it contrasts with methodological behaviorism in accepting feelings, states of mind and introspection as behaviors also subject to scientific investigation. Like methodological behaviorism, it rejects the reflex as a model of all behavior, and it defends the science of behavior as complementary to but independent of physiology. Radical behaviorism overlaps considerably with other western philosophical positions, such as American pragmatism.

Although John B. Watson mainly emphasized his position of methodological behaviorism throughout his career, Watson and Rosalie Rayner conducted the renowned Little Albert experiment (1920), a study in which Ivan Pavlov's theory to respondent conditioning was first applied to eliciting a fearful reflex of crying in a human infant, and this became the launching point for understanding covert behavior (or private events) in radical behaviorism. However, Skinner felt that aversive stimuli should only be experimented on with animals and spoke out against Watson for testing something so controversial on a human.

In 1959, Skinner observed the emotions of two pigeons by noting that they appeared angry because their feathers ruffled. The pigeons were placed together in an operant chamber, where they were aggressive as a consequence of previous reinforcement in the environment. Through stimulus control and subsequent discrimination training, whenever Skinner turned off the green light, the pigeons came to notice that the food reinforcer is discontinued following each peck and responded without aggression. Skinner concluded that humans also learn aggression and possess such emotions (as well as other private events) no differently than do nonhuman animals.

Experimental and conceptual innovations

As experimental behavioural psychology is related to behavioral neuroscience, we can date the first researches in the area were done in the beginning of 19th century. 

Later, this essentially philosophical position gained strength from the success of Skinner's early experimental work with rats and pigeons, summarized in his books The Behavior of Organisms and Schedules of Reinforcement. Of particular importance was his concept of the operant response, of which the canonical example was the rat's lever-press. In contrast with the idea of a physiological or reflex response, an operant is a class of structurally distinct but functionally equivalent responses. For example, while a rat might press a lever with its left paw or its right paw or its tail, all of these responses operate on the world in the same way and have a common consequence. Operants are often thought of as species of responses, where the individuals differ but the class coheres in its function-shared consequences with operants and reproductive success with species. This is a clear distinction between Skinner's theory and S–R theory.

Skinner's empirical work expanded on earlier research on trial-and-error learning by researchers such as Thorndike and Guthrie with both conceptual reformulations—Thorndike's notion of a stimulus-response "association" or "connection" was abandoned; and methodological ones—the use of the "free operant", so-called because the animal was now permitted to respond at its own rate rather than in a series of trials determined by the experimenter procedures. With this method, Skinner carried out substantial experimental work on the effects of different schedules and rates of reinforcement on the rates of operant responses made by rats and pigeons. He achieved remarkable success in training animals to perform unexpected responses, to emit large numbers of responses, and to demonstrate many empirical regularities at the purely behavioral level. This lent some credibility to his conceptual analysis. It is largely his conceptual analysis that made his work much more rigorous than his peers, a point which can be seen clearly in his seminal work Are Theories of Learning Necessary? in which he criticizes what he viewed to be theoretical weaknesses then common in the study of psychology. An important descendant of the experimental analysis of behavior is the Society for Quantitative Analysis of Behavior.

Relation to language

As Skinner turned from experimental work to concentrate on the philosophical underpinnings of a science of behavior, his attention turned to human language with his 1957 book Verbal Behavior and other language-related publications; Verbal Behavior laid out a vocabulary and theory for functional analysis of verbal behavior, and was strongly criticized in a review by Noam Chomsky.

Skinner did not respond in detail but claimed that Chomsky failed to understand his ideas, and the disagreements between the two and the theories involved have been further discussed. Innateness theory, which has been heavily critiqued, is opposed to behaviorist theory which claims that language is a set of habits that can be acquired by means of conditioning. According to some, the behaviorist account is a process which would be too slow to explain a phenomenon as complicated as language learning. What was important for a behaviorist's analysis of human behavior was not language acquisition so much as the interaction between language and overt behavior. In an essay republished in his 1969 book Contingencies of Reinforcement, Skinner took the view that humans could construct linguistic stimuli that would then acquire control over their behavior in the same way that external stimuli could. The possibility of such "instructional control" over behavior meant that contingencies of reinforcement would not always produce the same effects on human behavior as they reliably do in other animals. The focus of a radical behaviorist analysis of human behavior therefore shifted to an attempt to understand the interaction between instructional control and contingency control, and also to understand the behavioral processes that determine what instructions are constructed and what control they acquire over behavior. Recently, a new line of behavioral research on language was started under the name of relational frame theory.

Education

Behaviourism focuses on one particular view of learning: a change in external behaviour achieved through using reinforcement and repetition (Rote learning) to shape behavior of learners. Skinner found that behaviors could be shaped when the use of reinforcement was implemented. Desired behavior is rewarded, while the undesired behavior is not rewarded. Incorporating behaviorism into the classroom allowed educators to assist their students in excelling both academically and personally. In the field of language learning, this type of teaching was called the audio-lingual method, characterised by the whole class using choral chanting of key phrases, dialogues and immediate correction.

Within the behaviourist view of learning, the "teacher" is the dominant person in the classroom and takes complete control, evaluation of learning comes from the teacher who decides what is right or wrong. The learner does not have any opportunity for evaluation or reflection within the learning process, they are simply told what is right or wrong. The conceptualization of learning using this approach could be considered "superficial," as the focus is on external changes in behaviour, i.e., not interested in the internal processes of learning leading to behaviour change and has no place for the emotions involved in the process.

Operant conditioning

Operant conditioning was developed by B.F. Skinner in 1937 and deals with the management of environmental contingencies to change behavior. In other words, behavior is controlled by historical consequential contingencies, particularly reinforcement—a stimulus that increases the probability of performing behaviors, and punishment—a stimulus that decreases such probability. The core tools of consequences are either positive (presenting stimuli following a response), or negative (withdrawn stimuli following a response).

The following descriptions explains the concepts of four common types of consequences in operant conditioning:

  • Positive reinforcement: Providing a stimulus that an individual enjoys, seeks, or craves, in order to reinforce desired behaviors. For example, when a person is teaching a dog to sit, they pair the command "sit" with a treat. The treat is the positive reinforcement to the behavior of sitting. The key to making positive reinforcement effect is to reward the behavior immediately.
  • Negative reinforcement: Removing a stimulus that an individual does not desire to reinforce desired behaviors. For example, a child hates being nagged to clean his room. His mother reinforces his room cleaning by removing the undesired stimulus of nagging after he has cleaned. Another example would be putting on sunscreen before going outside. The negative effect is getting a sunburn, so by putting on sunscreen, the behavior in this case, you avoid the stimulus of getting a sunburn.
  • Positive punishment: Providing a stimulus that an individual does not desire to decrease undesired behaviors. An example of this would be spanking. If a child is doing something they have been warned not to do, the parent might spank them. The undesired stimulus would be the spanking, and by adding this stimulus, the goal is to have that behavior avoided. The key to this technique is that even though the title says positive, the meaning of positive here is "to add to." So, in order to stop the behavior, the parent adds the adverse stimulus (spanking). The biggest problem with this type of training though is that the trainee doesn't usually learn the desired behavior, rather it teaches the trainee to avoid the punisher.
  • Negative punishment: Removing a stimulus that an individual desires in order to decrease undesired behaviors. An example of this would be grounding a child for failing a test. Grounding in this example is taking away the child's ability to play video games. As long as it is clear that the ability to play video games was taken away because they failed a test, this is negative punishment. The key here is the connection to the behavior and the result of the behavior.

Classical experiment in operant conditioning, for example, the Skinner Box, "puzzle box" or operant conditioning chamber to test the effects of operant conditioning principles on rats, cats and other species. From the study of Skinner box, he discovered that the rats learned very effectively if they were rewarded frequently with food. Skinner also found that he could shape the rats' behavior through the use of rewards, which could, in turn, be applied to human learning as well.

Skinner's model was based on the premise that reinforcement is used for the desired actions or responses while punishment was used to stop the responses of the undesired actions that are not. This theory proved that humans or animals will repeat any action that leads to a positive outcome, and avoiding any action that leads to a negative outcome. The experiment with the pigeons showed that a positive outcome leads to learned behavior since the pigeon learned to peck the disc in return for the reward of food.

These historical consequential contingencies subsequently lead to (antecedent) stimulus control, but in contrast to respondent conditioning where antecedent stimuli elicit reflexive behavior, operant behavior is only emitted and therefore does not force its occurrence. It includes the following controlling stimuli:

  • Discriminative stimulus (Sd): An antecedent stimulus that increases the chance of the organism engaging in a behavior. One example of this occurred in Skinner's laboratory. Whenever the green light (Sd) appeared, it signaled the pigeon to perform the behavior of pecking because it learned in the past that each time it pecked, food was presented (the positive reinforcing stimulus).
  • Stimulus delta (S-delta): An antecedent stimulus that signals the organism not to perform a behavior since it was extinguished or punished in the past. One notable instance of this occurs when a person stops their car immediately after the traffic light turns red (S-delta). However, the person could decide to drive through the red light, but subsequently receive a speeding ticket (the positive punishing stimulus), so this behavior will potentially not reoccur following the presence of the S-delta.

Respondent conditioning

Although operant conditioning plays the largest role in discussions of behavioral mechanisms, respondent conditioning (also called Pavlovian or classical conditioning) is also an important behavior-analytic process that needs not refer to mental or other internal processes. Pavlov's experiments with dogs provide the most familiar example of the classical conditioning procedure. In the beginning, the dog was provided meat (unconditioned stimulus, UCS, naturally elicit a response that is not controlled) to eat, resulting in increased salivation (unconditioned response, UCR, which means that a response is naturally caused by UCS). Afterward, a bell ring was presented together with food to the dog. Although bell ring was a neutral stimulus (NS, meaning that the stimulus did not have any effect), dog would start to salivate when only hearing a bell ring after a number of pairings. Eventually, the neutral stimulus (bell ring) became conditioned. Therefore, salivation was elicited as a conditioned response (the response same as the unconditioned response), pairing up with meat—the conditioned stimulus)  Although Pavlov proposed some tentative physiological processes that might be involved in classical conditioning, these have not been confirmed. The idea of classical conditioning helped behaviorist John Watson discover the key mechanism behind how humans acquire the behaviors that they do, which was to find a natural reflex that produces the response being considered.

Watson's "Behaviourist Manifesto" has three aspects that deserve special recognition: one is that psychology should be purely objective, with any interpretation of conscious experience being removed, thus leading to psychology as the "science of behaviour"; the second one is that the goals of psychology should be to predict and control behaviour (as opposed to describe and explain conscious mental states); the third one is that there is no notable distinction between human and non-human behaviour. Following Darwin's theory of evolution, this would simply mean that human behaviour is just a more complex version in respect to behaviour displayed by other species.

In philosophy

Behaviorism is a psychological movement that can be contrasted with philosophy of mind. The basic premise of behaviorism is that the study of behavior should be a natural science, such as chemistry or physics. Initially behaviorism rejected any reference to hypothetical inner states of organisms as causes for their behavior, but B.F. Skinner's radical behaviorism reintroduced reference to inner states and also advocated for the study of thoughts and feelings as behaviors subject to the same mechanisms as external behavior. Behaviorism takes a functional view of behavior. According to Edmund Fantino and colleagues: "Behavior analysis has much to offer the study of phenomena normally dominated by cognitive and social psychologists. We hope that successful application of behavioral theory and methodology will not only shed light on central problems in judgment and choice but will also generate greater appreciation of the behavioral approach."

Behaviorist sentiments are not uncommon within philosophy of language and analytic philosophy. It is sometimes argued that Ludwig Wittgenstein defended a logical behaviorist position (e.g., the beetle in a box argument). In logical positivism (as held, e.g., by Rudolf Carnap and Carl Hempel), the meaning of psychological statements are their verification conditions, which consist of performed overt behavior. W. V. O. Quine made use of a type of behaviorism, influenced by some of Skinner's ideas, in his own work on language. Quine's work in semantics differed substantially from the empiricist semantics of Carnap which he attempted to create an alternative to, couching his semantic theory in references to physical objects rather than sensations. Gilbert Ryle defended a distinct strain of philosophical behaviorism, sketched in his book The Concept of Mind. Ryle's central claim was that instances of dualism frequently represented "category mistakes", and hence that they were really misunderstandings of the use of ordinary language. Daniel Dennett likewise acknowledges himself to be a type of behaviorist, though he offers extensive criticism of radical behaviorism and refutes Skinner's rejection of the value of intentional idioms and the possibility of free will.

This is Dennett's main point in "Skinner Skinned." Dennett argues that there is a crucial difference between explaining and explaining away… If our explanation of apparently rational behavior turns out to be extremely simple, we may want to say that the behavior was not really rational after all. But if the explanation is very complex and intricate, we may want to say not that the behavior is not rational, but that we now have a better understanding of what rationality consists in. (Compare: if we find out how a computer program solves problems in linear algebra, we don't say it's not really solving them, we just say we know how it does it. On the other hand, in cases like Weizenbaum's ELIZA program, the explanation of how the computer carries on a conversation is so simple that the right thing to say seems to be that the machine isn't really carrying on a conversation, it's just a trick.)

— Curtis Brown, "Behaviorism: Skinner and Dennett", Philosophy of Mind

Law of effect and trace conditioning

Molecular versus molar behaviorism

Skinner's view of behavior is most often characterized as a "molecular" view of behavior; that is, behavior can be decomposed into atomistic parts or molecules. This view is inconsistent with Skinner's complete description of behavior as delineated in other works, including his 1981 article "Selection by Consequences". Skinner proposed that a complete account of behavior requires understanding of selection history at three levels: biology (the natural selection or phylogeny of the animal); behavior (the reinforcement history or ontogeny of the behavioral repertoire of the animal); and for some species, culture (the cultural practices of the social group to which the animal belongs). This whole organism then interacts with its environment. Molecular behaviorists use notions from melioration theory, negative power function discounting or additive versions of negative power function discounting.

Molar behaviorists, such as Howard Rachlin, Richard Herrnstein, and William Baum, argue that behavior cannot be understood by focusing on events in the moment. That is, they argue that behavior is best understood as the ultimate product of an organism's history and that molecular behaviorists are committing a fallacy by inventing fictitious proximal causes for behavior. Molar behaviorists argue that standard molecular constructs, such as "associative strength", are better replaced by molar variables such as rate of reinforcement. Thus, a molar behaviorist would describe "loving someone" as a pattern of loving behavior over time; there is no isolated, proximal cause of loving behavior, only a history of behaviors (of which the current behavior might be an example) that can be summarized as "love".

Theoretical behaviorism

Skinner's radical behaviorism has been highly successful experimentally, revealing new phenomena with new methods, but Skinner's dismissal of theory limited its development. Theoretical behaviorism recognized that a historical system, an organism, has a state as well as sensitivity to stimuli and the ability to emit responses. Indeed, Skinner himself acknowledged the possibility of what he called "latent" responses in humans, even though he neglected to extend this idea to rats and pigeons. Latent responses constitute a repertoire, from which operant reinforcement can select. Theoretical behaviorism links between the brain and the behavior that provides a real understanding of the behavior. Rather than a mental presumption of how brain-behavior relates.

Behavior analysis and culture

Cultural analysis has always been at the philosophical core of radical behaviorism from the early days (as seen in Skinner's Walden Two, Science & Human Behavior, Beyond Freedom & Dignity, and About Behaviorism).

During the 1980s, behavior analysts, most notably Sigrid Glenn, had a productive interchange with cultural anthropologist Marvin Harris (the most notable proponent of "cultural materialism") regarding interdisciplinary work. Very recently, behavior analysts have produced a set of basic exploratory experiments in an effort toward this end. Behaviorism is also frequently used in game development, although this application is controversial.

Behavior informatics and behavior computing

With the fast growth of big behavioral data and applications, behavior analysis is ubiquitous. Understanding behavior from the informatics and computing perspective becomes increasingly critical for in-depth understanding of what, why and how behaviors are formed, interact, evolve, change and affect business and decision. Behavior informatics and behavior computing deeply explore behavior intelligence and behavior insights from the informatics and computing perspectives.

Criticisms and limitations

In the second half of the 20th century, behaviorism was largely eclipsed as a result of the cognitive revolution. This shift was due to radical behaviorism being highly criticized for not examining mental processes, and this led to the development of the cognitive therapy movement. In the mid-20th century, three main influences arose that would inspire and shape cognitive psychology as a formal school of thought:

  • Noam Chomsky's 1959 critique of behaviorism, and empiricism more generally, initiated what would come to be known as the "cognitive revolution".
  • Developments in computer science would lead to parallels being drawn between human thought and the computational functionality of computers, opening entirely new areas of psychological thought. Allen Newell and Herbert Simon spent years developing the concept of artificial intelligence (AI) and later worked with cognitive psychologists regarding the implications of AI. The effective result was more of a framework conceptualization of mental functions with their counterparts in computers (memory, storage, retrieval, etc.)
  • Formal recognition of the field involved the establishment of research institutions such as George Mandler's Center for Human Information Processing in 1964. Mandler described the origins of cognitive psychology in a 2002 article in the Journal of the History of the Behavioral Sciences

In the early years of cognitive psychology, behaviorist critics held that the empiricism it pursued was incompatible with the concept of internal mental states. Cognitive neuroscience, however, continues to gather evidence of direct correlations between physiological brain activity and putative mental states, endorsing the basis for cognitive psychology.

Behavior therapy

Behavior therapy is a term referring to different types of therapies that treat mental health disorders. It identifies and helps change people's unhealthy behaviors or destructive behaviors through learning theory and conditioning. Ivan Pavlov's classical conditioning, as well as counterconditioning are the basis for much of clinical behavior therapy, but also includes other techniques, including operant conditioning—or contingency management, and modeling (sometimes called observational learning). A frequently noted behavior therapy is systematic desensitization (graduated exposure therapy), which was first demonstrated by Joseph Wolpe and Arnold Lazarus.

21st-century behaviorism (behavior analysis)

Applied behavior analysis (ABA)—also called behavioral engineering—is a scientific discipline that applies the principles of behavior analysis to change behavior. ABA derived from much earlier research in the Journal of the Experimental Analysis of Behavior, which was founded by B.F. Skinner and his colleagues at Harvard University. Nearly a decade after the study "The psychiatric nurse as a behavioral engineer" (1959) was published in that journal, which demonstrated how effective the token economy was in reinforcing more adaptive behavior for hospitalized patients with schizophrenia and intellectual disability, it led to researchers at the University of Kansas to start the Journal of Applied Behavior Analysis in 1968.

Although ABA and behavior modification are similar behavior-change technologies in that the learning environment is modified through respondent and operant conditioning, behavior modification did not initially address the causes of the behavior (particularly, the environmental stimuli that occurred in the past), or investigate solutions that would otherwise prevent the behavior from reoccurring. As the evolution of ABA began to unfold in the mid-1980s, functional behavior assessments (FBAs) were developed to clarify the function of that behavior, so that it is accurately determined which differential reinforcement contingencies will be most effective and less likely for aversive consequences to be administered. In addition, methodological behaviorism was the theory underpinning behavior modification since private events were not conceptualized during the 1970s and early 1980s, which contrasted from the radical behaviorism of behavior analysis. ABA—the term that replaced behavior modification—has emerged into a thriving field.

The independent development of behaviour analysis outside the United States also continues to develop. In the US, the American Psychological Association (APA) features a subdivision for Behavior Analysis, titled APA Division 25: Behavior Analysis, which has been in existence since 1964, and the interests among behavior analysts today are wide-ranging, as indicated in a review of the 30 Special Interest Groups (SIGs) within the Association for Behavior Analysis International (ABAI). Such interests include everything from animal behavior and environmental conservation, to classroom instruction (such as direct instruction and precision teaching), verbal behavior, developmental disabilities and autism, clinical psychology (i.e., forensic behavior analysis), behavioral medicine (i.e., behavioral gerontology, AIDS prevention, and fitness training), and consumer behavior analysis.

The field of applied animal behavior—a sub-discipline of ABA that involves training animals—is regulated by the Animal Behavior Society, and those who practice this technique are called applied animal behaviorists. Research on applied animal behavior has been frequently conducted in the Applied Animal Behaviour Science journal since its founding in 1974.

ABA has also been particularly well-established in the area of developmental disabilities since the 1960s, but it was not until the late 1980s that individuals diagnosed with autism spectrum disorders were beginning to grow so rapidly and groundbreaking research was being published that parent advocacy groups started demanding for services throughout the 1990s, which encouraged the formation of the Behavior Analyst Certification Board, a credentialing program that certifies professionally trained behavior analysts on the national level to deliver such services. Nevertheless, the certification is applicable to all human services related to the rather broad field of behavior analysis (other than the treatment for autism), and the ABAI currently has 14 accredited MA and Ph.D. programs for comprehensive study in that field.

Early behavioral interventions (EBIs) based on ABA are empirically validated for teaching children with autism and has been proven as such for over the past five decades. Since the late 1990s and throughout the twenty-first century, early ABA interventions have also been identified as the treatment of choice by the US Surgeon General, American Academy of Pediatrics, and US National Research Council.

Discrete trial training—also called early intensive behavioral intervention—is the traditional EBI technique implemented for thirty to forty hours per week that instructs a child to sit in a chair, imitate fine and gross motor behaviors, as well as learn eye contact and speech, which are taught through shaping, modeling, and prompting, with such prompting being phased out as the child begins mastering each skill. When the child becomes more verbal from discrete trials, the table-based instructions are later discontinued, and another EBI procedure known as incidental teaching is introduced in the natural environment by having the child ask for desired items kept out of their direct access, as well as allowing the child to choose the play activities that will motivate them to engage with their facilitators before teaching the child how to interact with other children their own age.

A related term for incidental teaching, called pivotal response treatment (PRT), refers to EBI procedures that exclusively entail twenty-five hours per week of naturalistic teaching (without initially using discrete trials). Current research is showing that there is a wide array of learning styles and that is the children with receptive language delays who initially require discrete trials to acquire speech.

Organizational behavior management, which applies contingency management procedures to model and reinforce appropriate work behavior for employees in organizations, has developed a particularly strong following within ABA, as evidenced by the formation of the OBM Network and Journal of Organizational Behavior Management, which was rated the third-highest impact journal in applied psychology by ISI JOBM rating.

Modern-day clinical behavior analysis has also witnessed a massive resurgence in research, with the development of relational frame theory (RFT), which is described as an extension of verbal behavior and a "post-Skinnerian account of language and cognition." RFT also forms the empirical basis for acceptance and commitment therapy, a therapeutic approach to counseling often used to manage such conditions as anxiety and obesity that consists of acceptance and commitment, value-based living, cognitive defusion, counterconditioning (mindfulness), and contingency management (positive reinforcement). Another evidence-based counseling technique derived from RFT is the functional analytic psychotherapy known as behavioral activation that relies on the ACL model—awareness, courage, and love—to reinforce more positive moods for those struggling with depression.

Incentive-based contingency management (CM) is the standard of care for adults with substance-use disorders; it has also been shown to be highly effective for other addictions (i.e., obesity and gambling). Although it does not directly address the underlying causes of behavior, incentive-based CM is highly behavior analytic as it targets the function of the client's motivational behavior by relying on a preference assessment, which is an assessment procedure that allows the individual to select the preferred reinforcer (in this case, the monetary value of the voucher, or the use of other incentives, such as prizes). Another evidence-based CM intervention for substance abuse is community reinforcement approach and family training that uses FBAs and counterconditioning techniques—such as behavioral skills training and relapse prevention—to model and reinforce healthier lifestyle choices which promote self-management of abstinence from drugs, alcohol, or cigarette smoking during high-risk exposure when engaging with family members, friends, and co-workers.

While schoolwide positive behavior support consists of conducting assessments and a task analysis plan to differentially reinforce curricular supports that replace students' disruptive behavior in the classroom, pediatric feeding therapy incorporates a liquid chaser and chin feeder to shape proper eating behavior for children with feeding disorders. Habit reversal training, an approach firmly grounded in counterconditioning which uses contingency management procedures to reinforce alternative behavior, is currently the only empirically validated approach for managing tic disorders.

Some studies on exposure (desensitization) therapies—which refer to an array of interventions based on the respondent conditioning procedure known as habituation and typically infuses counterconditioning procedures, such as meditation and breathing exercises—have recently been published in behavior analytic journals since the 1990s, as most other research are conducted from a cognitive-behavior therapy framework. When based on a behavior analytic research standpoint, FBAs are implemented to precisely outline how to employ the flooding form of desensitization (also called direct exposure therapy) for those who are unsuccessful in overcoming their specific phobia through systematic desensitization (also known as graduated exposure therapy). These studies also reveal that systematic desensitization is more effective for children if used in conjunction with shaping, which is further termed contact desensitization, but this comparison has yet to be substantiated with adults.

Other widely published behavior analytic journals include Behavior Modification, The Behavior Analyst, Journal of Positive Behavior Interventions, Journal of Contextual Behavioral Science, The Analysis of Verbal Behavior, Behavior and Philosophy, Behavior and Social Issues, and The Psychological Record.

Cognitive-behavior therapy

Cognitive-behavior therapy (CBT) is a behavior therapy discipline that often overlaps considerably with the clinical behavior analysis subfield of ABA, but differs in that it initially incorporates cognitive restructuring and emotional regulation to alter a person's cognition and emotions.

A popularly noted counseling intervention known as dialectical behavior therapy (DBT) includes the use of a chain analysis, as well as cognitive restructuring, emotional regulation, distress tolerance, counterconditioning (mindfulness), and contingency management (positive reinforcement). DBT is quite similar to acceptance and commitment therapy, but contrasts in that it derives from a CBT framework. Although DBT is most widely researched for and empirically validated to reduce the risk of suicide in psychiatric patients with borderline personality disorder, it can often be applied effectively to other mental health conditions, such as substance abuse, as well as mood and eating disorders.

Most research on exposure therapies (also called desensitization)—ranging from eye movement desensitization and reprocessing therapy to exposure and response prevention—are conducted through a CBT framework in non-behavior analytic journals, and these enhanced exposure therapies are well-established in the research literature for treating phobic, post-traumatic stress, and other anxiety disorders (such as obsessive-compulsive disorder, or OCD).

Cognitive-based behavioral activation (BA)—the psychotherapeutic approach used for depression—is shown to be highly effective and is widely used in clinical practice. Some large randomized control trials have indicated that cognitive-based BA is as beneficial as antidepressant medications but more efficacious than traditional cognitive therapy. Other commonly used clinical treatments derived from behavioral learning principles that are often implemented through a CBT model include community reinforcement approach and family training, and habit reversal training for substance abuse and tics, respectively.

Experimental psychology

From Wikipedia, the free encyclopedia

Experimental psychology refers to work done by those who apply experimental methods to psychological study and the underlying processes. Experimental psychologists employ human participants and animal subjects to study a great many topics, including (among others) sensation & perception, memory, cognition, learning, motivation, emotion; developmental processes, social psychology, and the neural substrates of all of these.

History

Early experimental psychology

Wilhelm Wundt

Experimental psychology emerged as a modern academic discipline in the 19th century when Wilhelm Wundt introduced a mathematical and experimental approach to the field. Wundt founded the first psychology laboratory in Leipzig, Germany. Other experimental psychologists, including Hermann Ebbinghaus and Edward Titchener, included introspection in their experimental methods.

Charles Bell

Charles Bell was a British physiologist whose main contribution to the medical and scientific community was his research on the nervous system. He wrote a pamphlet summarizing his research on rabbits. His research concluded that sensory nerves enter at the posterior (dorsal) roots of the spinal cord, and motor nerves emerge from the anterior (ventral) roots of the spinal cord. Eleven years later, a French physiologist, Francois Magendie, published the same findings without being aware of Bell's research. As a result of Bell not publishing his research, this discovery was called the Bell-Magendie law to honor both individuals. Bell's discovery disproved the belief that nerves transmitted either vibrations or spirits.

Ernst Heinrich Weber

Ernst Heinrich Weber, a German physician, is credited as one of experimental psychology's founders. Weber's main interests were the sense of touch and kinesthesis. His most memorable contribution to the field of experimental psychology is the suggestion that judgments of sensory differences are relative and not absolute. This relativity is expressed in "Weber's Law," which suggests that the just-noticeable difference or jnd is a constant proportion of the ongoing stimulus level. Weber's Law is stated as an equation:

where is the original intensity of stimulation, is the addition to it required for the difference to be perceived (the jnd), and k is a constant. Thus, for k to remain constant, must rise as I increases. Weber's law is considered to be the first quantitative law in the history of psychology.

Gustav Fechner

Fechner published in 1860 what is considered to be the first work of experimental psychology, "Elemente der Psychophysik." Some historians date the beginning of experimental psychology to the publication of "Elemente." Ernst Heinrich Weber was not a psychologist, but it was Fechner who realized the importance of Weber's research to psychology. Weber's law and Fechner's law was published in Fechner's work, "Elemente der Psychophysik," and Fechner, a student of Weber named his first law in honor of his mentor. Fechner was profoundly interested in establishing a scientific study of the mind-body relationship, which became known as psychophysics. Much of Fechner's research focused on the measurement of psychophysical thresholds and just-noticeable differences. He invented the psychophysical method of limits, the method of constant stimuli, and the method of adjustment, which are still in use.

Oswald Külpe

Oswald Külpe is the main founder of the Würzburg School in Germany. He was a pupil of Wilhelm Wundt for about twelve years. Unlike Wundt, Külpe believed experiments were possible to test higher mental processes. In 1883 he wrote Grundriss der Psychologie, which had strictly scientific facts and no mention of thought. The lack of thought in his book is odd because the Würzburg School put a lot of emphasis on mental set and imageless thought.

Würzburg School

The work of the Würzburg School was a milestone in the development of experimental psychology. The School was founded by a group of psychologists led by Oswald Külpe, and it provided an alternative to the structuralism of Edward Titchener and Wilhelm Wundt. Those in the School focused mainly on mental operations such as mental set (Einstellung) and imageless thought. Mental set affects perception and problem solving without the awareness of the individual; it can be triggered by instructions or by experience. Similarly, according to Külpe, imageless thought consists of pure mental acts that do not involve mental images. William Bryan, an American student, working in Külpe's laboratory, provided an example of mental set. Bryan presented subjects with cards that had nonsense syllables written on them in various colors. The subjects were told to attend to the syllables, and in consequence, they did not remember the colors of the nonsense syllables. Such results made people question the validity of introspection as a research tool, leading to a decline in voluntarism and structuralism. The work of the Würzburg School later influenced many Gestalt psychologists, including Max Wertheimer.

George Trumbull Ladd

George Trumbull Ladd introduced experimental psychology into the United States and founded Yale University's psychological laboratory in 1879. In 1887, Ladd published Elements of Physiological Psychology, the first American textbook that extensively discussed experimental psychology. Between Ladd's founding of the Yale Laboratory and his textbook, the center of experimental psychology in the US shifted to Johns Hopkins University, where George Hall and Charles Sanders Peirce were extending and qualifying Wundt's work.

Charles Sanders Peirce

Charles Sanders Peirce
 
Joseph Jastrow

With his student Joseph Jastrow, Charles S. Peirce randomly assigned volunteers to a blinded, repeated-measures design to evaluate their ability to discriminate weights. Peirce's experiment inspired other researchers in psychology and education, which developed a research tradition of randomized experiments in laboratories and specialized textbooks in the 1800s. The Peirce–Jastrow experiments were conducted as part of Peirce's pragmatic program to understand human perception; other studies considered perception of light, etc. While Peirce was making advances in experimental psychology and psychophysics, he was also developing a theory of statistical inference, which was published in "Illustrations of the Logic of Science" (1877–78) and "A Theory of Probable Inference" (1883); both publications that emphasized the importance of randomization-based inference in statistics. To Peirce and to experimental psychology belongs the honor of having invented randomized experiments decades before the innovations of Jerzy Neyman and Ronald Fisher in agriculture.

Peirce's pragmaticist philosophy also included an extensive theory of mental representations and cognition, which he studied under the name of semiotics. Peirce's student Joseph Jastrow continued to conduct randomized experiments throughout his distinguished career in experimental psychology, much of which would later be recognized as cognitive psychology. There has been a resurgence of interest in Peirce's work in cognitive psychology. Another student of Peirce, John Dewey, conducted experiments on human cognition, particularly in schools, as part of his "experimental logic" and "public philosophy."

20th century

In the middle of the 20th century, behaviorism became a dominant paradigm within psychology, especially in the United States. This led to some neglect of mental phenomena within experimental psychology. In Europe, this was less the case, as European psychology was influenced by psychologists such as Sir Frederic Bartlett, Kenneth Craik, W.E. Hick, and Donald Broadbent, who focused on topics such as thinking, memory, and attention. This laid the foundations for the subsequent development of cognitive psychology.

In the latter half of the 20th century, the phrase "experimental psychology" had shifted in meaning due to the expansion of psychology as a discipline and the growth in its sub-disciplines. Experimental psychologists use a range of methods and do not confine themselves to a strictly experimental approach, partly because developments in the philosophy of science have affected the exclusive prestige of experimentation. In contrast, experimental methods are now widely used in fields such as developmental and social psychology, which were not previously part of experimental psychology. The phrase continues in use in the titles of a number of well-established, high prestige learned societies and scientific journals, as well as some university courses of study in psychology.

Institutional review board (IRB)

In 1974, the National Research Act established the existence of the institutional review board in the United States following several controversial experiments. Institutional Review Boards (IRBs) play an important role in monitoring the conduct of psychological experiments. Their presence is required by law at institutions such as universities where psychological research occurs. Their purpose is to make sure that experiments do not violate ethical codes or legal requirements; thus they protect human subjects from physical or psychological harm and assure the humane treatment of animal subjects. An IRB must review the procedure to be used in each experiment before that experiment may begin. The IRB also assures that human participants give informed consent in advance; that is, the participants are told the general nature of the experiment and what will be required of them. There are three types of review that may be undertaken by an IRB - exempt, expedited, and full review. More information is available on the main IRB page.

Methodology

Sound methodology is essential to the study of complex behavioral and mental processes, and this implies, especially, the careful definition and control of experimental variables. The research methodologies employed in experimental psychology utilize techniques in research to seek to uncover new knowledge or validate existing claims. Typically, this entails a number of stages, including selecting a sample, gathering data from this sample, and evaluating this data. From assumptions made by researchers when undertaking a project, to the scales used, the research design, and data analysis, proper methodology in experimental psychology is made up of several critical stages.

Assumptions

Empiricism

Perhaps the most basic assumption of science is that factual statements about the world must ultimately be based on observations of the world. This notion of empiricism requires that hypotheses and theories be tested against observations of the natural world rather than on a priori reasoning, intuition, or revelation.

Testability

Closely related to empiricism is the idea that, to be useful, a scientific law or theory must be testable with available research methods. If a theory cannot be tested in any conceivable way then many scientists consider the theory to be meaningless. Testability implies falsifiability, which is the idea that some set of observations could prove the theory to be incorrect. Testability has been emphasized in psychology because influential or well-known theories like those of Freud have been difficult to test.

Determinism

Experimental psychologists, like most scientists, accept the notion of determinism. This is the assumption that any state of an object or event is determined by prior states. In other words, behavioral or mental phenomena are typically stated in terms of cause and effect. If a phenomenon is sufficiently general and widely confirmed, it may be called a "law"; psychological theories serve to organize and integrate laws.

Parsimony

Another guiding idea of science is parsimony, the search for simplicity. For example, most scientists agree that if two theories handle a set of empirical observations equally well, we should prefer the simpler or more parsimonious of the two. A notable early argument for parsimony was stated by the medieval English philosopher William of Occam, and for this reason, the principle of parsimony is often referred to as Occam's razor.

Operational definition

Some well-known behaviorists such as Edward C. Tolman and Clark Hull popularized the idea of operationism, or operational definition. Operational definition implies that a concept be defined in terms of concrete, observable procedures. Experimental psychologists attempt to define currently unobservable phenomena, such as mental events, by connecting them to observations by chains of reasoning.

Reliability and Validity

Reliability

Reliability measures the consistency or repeatability of an observation. For example, one way to assess reliability is the "test-retest" method, done by measuring a group of participants at one time and then testing them a second time to see if the results are consistent. Because the first test itself may alter the results of a second test, other methods are often used. For example, in the "split-half" measure, a group of participants is divided at random into two comparable sub-groups, and reliability is measured by comparing the test results from these groups, It is important to note that a reliable measure need not yield a valid conclusion.

Validity

Validity measures the relative accuracy or correctness of conclusions drawn from a study. To determine the validity of a measurement quantitatively, it must be compared with a criterion. For example, to determine the validity of a test of academic ability, that test might be given to a group of students and the results correlated with the grade-point averages of the individuals in that group. As this example suggests, there is often controversy in the selection of appropriate criteria for a given measure. In addition, a conclusion can only be valid to the extent that the observations upon which it is based are reliable.

Several types of validity have been distinguished, as follows:

Internal validity

Internal validity refers to the extent to which a set of research findings provides compelling information about causality. High internal validity implies that the experimental design of a study excludes extraneous influences, such that one can confidently conclude that variations in the independent variable caused any observed changes in the dependent variable.

External validity

External Validity refers to the extent to which the outcome of an experiment can be generalized to apply to other situations than those of the experiment - for example, to other people, other physical or social environments, or even other cultures.

Construct validity

Construct validity refers to the extent to which the independent and dependent variables in a study represent the abstract hypothetical variables of interest. In other words, it has to do with whether the manipulated and/or measured variables in a study accurately reflect the variables the researcher hoped to manipulate. Construct validity also reflects the quality of one's operational definitions. If a researcher has done a good job of converting the abstract to the observable, construct validity is high.

Conceptual validity

Conceptual validity refers to how well specific research maps onto the broader theory that it was designed to test. Conceptual and construct validity have a lot in common, but conceptual validity relates a study to broad theoretical issues whereas construct validity has more to do with specific manipulations and measures.

Scales of measurement

Measurement can be defined as "the assignment of numerals to objects or events according to rules." Almost all psychological experiments involve some sort of measurement, if only to determine the reliability and validity of results, and of course measurement is essential if results are to be relevant to quantitative theories.

The rule for assigning numbers to a property of an object or event is called a "scale". Following are the basic scales used in psychological measurement.

Nominal measurement

In a nominal scale, numbers are used simply as labels – a letter or name would do as well. Examples are the numbers on the shirts of football or baseball players. The labels are more useful if the same label can be given to more than one thing, meaning that the things are equal in some way, and can be classified together.

Ordinal measurement

An ordinal scale arises from the ordering or ranking objects, so that A is greater than B, B is greater than C, and so on. Many psychological experiments yield numbers of this sort; for example, a participant might be able to rank odors such that A is more pleasant than B, and B is more pleasant than C, but these rankings ("1, 2, 3 ...") would not tell by how much each odor differed from another. Some statistics can be computed from ordinal measures – for example, median, percentile, and order correlation – but others, such as standard deviation, cannot properly be used.

Interval measurement

An interval scale is constructed by determining the equality of differences between the things measured. That is, numbers form an interval scale when the differences between the numbers correspond to differences between the properties measured. For instance, one can say that the difference between 5 and 10 degrees on a Fahrenheit thermometer equals the difference between 25 and 30, but it is meaningless to say that something with a temperature of 20 degrees Fahrenheit is "twice as hot" as something with a temperature of 10 degrees. (Such ratios are meaningful on an absolute temperature scale such as the Kelvin scale. See next section.) "Standard scores" on an achievement test are said to be measurements on an interval scale, but this is difficult to prove.

Ratio measurement

A ratio scale is constructed by determining the equality of ratios. For example, if, on a balance instrument, object A balances two identical objects B, then one can say that A is twice as heavy as B and can give them appropriate numbers, for example "A weighs 2 grams" and "B weighs 1 gram". A key idea is that such ratios remain the same regardless of the scale units used; for example, the ratio of A to B remains the same whether grams or ounces are used. Length, resistance, and Kelvin temperature are other things that can be measured on ratio scales. Some psychological properties such as the loudness of a sound can be measured on a ratio scale.

Research design

One-way designs

The simplest experimental design is a one-way design, in which there is only one independent variable. The simplest kind of one-way design involves just two-groups, each of which receives one value of the independent variable. A two-group design typically consists of an experimental group (a group that receives treatment) and a control group (a group that does not receive treatment).

The one-way design may be expanded to a one-way, multiple groups design. Here a single independent variable takes on three or more levels. This type of design is particularly useful because it can help to outline a functional relationship between the independent and dependent variables.

Factorial designs

One-way designs are limited in that they allow researchers to look at only one independent variable at a time, whereas many phenomena of interest are dependent on multiple variables. Because of this, R.A Fisher popularized the use of factorial designs. Factorial designs contain two or more independent variables that are completely "crossed," which means that every level each independent variable appears in combination with every level of all other independent variables. Factorial designs carry labels that specify the number of independent variables and the number of levels of each independent variable there are in the design. For example, a 2x3 factorial design has two independent variables (because there are two numbers in the description), the first variable having two levels and the second having three.

Main effects and interactions

The effects of independent variables in factorial studies, taken singly, are referred to as main effects. This refers to the overall effect of an independent variable, averaging across all levels of the other independent variables. A main effect is the only effect detectable in a one-way design. Often more important than main effects are "interactions", which occur when the effect of one independent variable on a dependent variable depends on the level of a second independent variable. For example, the ability to catch a ball (dependent variable) might depend on the interaction of visual acuity (independent variable #1) and the size of the ball being caught (independent variable #2). A person with good eyesight might catch a small ball most easily, and person with very poor eyesight might do better with a large ball, so the two variables can be said to interact.

Within- and between-subjects designs

Two basic approaches to research design are within-subjects design and between-subjects design. In within-subjects or repeated measures designs, each participant serves in more than one or perhaps all of the conditions of a study. In between-subjects designs each participant serves in only one condition of an experiment. Within-subjects designs have significant advantages over between-subjects designs, especially when it comes to complex factorial designs that have many conditions. In particular, within-subjects designs eliminate person confounds, that is, they get rid of effects caused by differences among subjects that are irrelevant to the phenomenon under study. However, the within-subject design has the serious disadvantage of possible sequence effects. Because each participant serves in more than one condition, the passage of time or the performance of an earlier task may affect the performance of a later task. For example, a participant might learn something from the first task that affects the second. 

Research in Experimental Psychology

Experiments

The use of experimental methods was perhaps the main characteristic by which psychology became distinguishable from philosophy in the late 19th century. Ever since then experiments have been an integral part of most psychological research. Following is a sample of some major areas that use experimental methods. In experiments, human participants often respond to visual, auditory or other stimuli, following instructions given by an experimenter; animals may be similarly "instructed" by rewarding appropriate responses. Since the 1990s, computers have commonly been used to automate stimulus presentation and behavioral measurement in the laboratory. Behavioral experiments with both humans and animals typically measure reaction time, choices among two or more alternatives, and/or response rate or strength; they may also record movements, facial expressions, or other behaviors. Experiments with humans may also obtain written responses before, during, and after experimental procedures. Psychophysiological experiments, on the other hand, measure brain or (mostly in animals) single-cell activation during the presentation of a stimulus using methods such as fMRI, EEG, PET or similar.

Control of extraneous variables, minimizing the potential for experimenter bias, counterbalancing the order of experimental tasks, adequate sample size, the use of operational definitions, emphasis on both the reliability and validity of results, and proper statistical analysis are central to experimental methods in psychology. Because an understanding of these matters is important to the interpretation of data in almost all fields of psychology, undergraduate programs in psychology usually include mandatory courses in research methods and statistics.

A crucial experiment is an experiment that is intended to test several hypotheses at the same time. Ideally, one hypothesis may be confirmed and all the others rejected. However, the data may also be consistent with several hypotheses, a result that calls for further research to narrow down the possibilities.

A pilot study may be run before a major experiment, in order to try out different procedures, determine optimal values of the experimental variables, or uncover weaknesses in experimental design. The pilot study may not be an experiment as usually defined; it might, for example, consist simply of self-reports.

In a field experiment, participants are observed in a naturalistic setting outside the laboratory. Field experiments differ from field studies in that some part of the environment (field) is manipulated in a controlled way (for example, researchers give different kinds of toys to two different groups of children in a nursery school). Control is typically more lax than it would be in a laboratory setting.

Other methods of research such as case study, interview, opinion polls and naturalistic observation, are often used by psychologists. These are not experimental methods, as they lack such aspects as well-defined, controlled variables, randomization, and isolation from unwanted variables.

Cognitive psychology

Some of the major topics studied by cognitive psychologists are memory, learning, problem solving, and attention. Most cognitive experiments are done in a lab instead of a social setting; this is done mainly to provide maximum control of experimental variables and minimal interference from irrelevant events and other aspects of the situation. A great many experimental methods are used; frequently used methods are described on the main pages of the topics just listed. In addition to studying behavior, experimenters may use EEG or fMRI to help understand how the brain carries out cognitive processes, sometimes in conjunction with computational modelling. They may also study patients with focal brain damage or neurologic disease (see cognitive neuropsychology) or use brain stimulation techniques like transcranial magnetic stimulation to help confirm the causal role and specific functional contribution of neural regions or modules.

Animal cognition

Animal cognition refers to the mental capacities of non-human animals, and research in this field often focuses on matters similar to those of interest to cognitive psychologists using human participants. Cognitive studies using animals can often control conditions more closely and use methods not open to research with humans. In addition, processes such as conditioning my appear in simpler form in animals, certain animals display unique capacities (such as echo location in bats) that clarify important cognitive functions, and animal studies often have important implications for the survival and evolution of species.

Sensation and perception

Experiments on sensation and perception have a very long history in experimental psychology (see History above). Experimenters typically manipulate stimuli affecting vision, hearing, touch, smell, taste and proprioception. Sensory measurement plays a large role in the field, covering many aspects of sensory performance - for example, minimum discriminable differences in brightness or the detection of odors; such measurement involves the use of instruments such as the oscillator, attenuator, stroboscope, and many others listed earlier in this article. Experiments also probe subtle phenomena such as visual illusions, or the emotions aroused by stimuli of different sorts.

Behavioral psychology

The behavioristic approach to psychology reached its peak of popularity in the mid-twentieth century but still underlies much experimental research and clinical application. Its founders include such figures as Ivan Pavlov, John B. Watson, and B.F. Skinner. Pavlov's experimental study of the digestive system in dogs led to extensive experiments through which he established the basic principles of classical conditioning. Watson popularized the behaviorist approach to human behavior; his experiments with Little Albert are particularly well known. Skinner distinguished operant conditioning from classical conditioning and established the experimental analysis of behavior as a major component in the subsequent development of experimental psychology.

Social psychology

Social psychologists use both empirical research and experimental methods to study the effects of social interactions on individuals' thoughts, feelings, and behaviors. Social psychologists use experimental methods, both within and outside the laboratory, and there have been several key experiments done in the past few centuries. The Triplett experiment, one of the first social psychology experiments conducted in 1898 by Norman Triplett, noticed that the presence of others had an effect on children's performance times. Other widely cited experiments in social psychology are projects like the Stanford prison experiment conducted by Philip Zimbardo in 1971 and the Milgram obedience experiment by Stanley Milgram. In both experiments ordinary individuals were induced to engage in remarkably cruel behavior, suggesting that such behavior could be influenced by social pressure. Zimbardo's experiment noted the effect of conformity to specific roles in society and the social world. Milgram's study looked at the role of authority in shaping behavior, even when it had adverse effects on another person. Because of possible negative effects on the participants, neither of these experiments could be legally performed in the United States today. These two experiments also took place during the era prior to the existence of IRBs, and most likely played a role in the establishment of such boards. 

Experimental instruments

Instruments used in experimental psychology evolved along with technical advances and with the shifting demands of experiments. The earliest instruments, such as the Hipp Chronoscope and the kymograph, were originally used for other purposes. The list below exemplifies some of the different instruments used over the years. These are only a few core instruments used in current research.

Hipp chronoscope / chronograph

This instrument, invented by Matthäus Hipp around 1850, uses a vibrating reed to tick off time in 1000ths of a second. Originally designed for experiments in physics, it was later adapted to study the speed of bullets. After then being introduced to physiology, it was finally used in psychology to measure reaction time and the duration of mental processes.

Stereoscope

The first stereoscope was invented by Wheatstone in 1838. It presents two slightly different images, one to each eye, at the same time. Typically the images are photographs of the same object taken from camera positions that mimic the position and separation of the eyes in the head. When one looks through the stereoscope the photos fuse into a single image that conveys a powerful sense of depth and solidity.

Kymograph

Developed by Carl Ludwig in the 19th century, the kymograph is a revolving drum on which a moving stylus tracks the size of some measurement as a function of time. The kymograph is similar to the polygraph, which has a strip of paper moving under one or more pens. The kymograph was originally used to measure blood pressure and it later was used to measure muscle contractions and speech sounds. In psychology, it was often used to record response times.

Photokymographs

This device is a photographic recorder. It used mirrors and light to record the photos. Inside a small box with a slit for light there are two drive rollers with film connecting the two. The light enters through the slit to record on the film. Some photokymographs have a lens so an appropriate speed for the film can be reached.

Galvanometer

The galvanometer is an early instrument used to measure the strength of an electric current. Hermann von Helmholtz used it to detect the electrical signals generated by nerve impulses, and thus to measure the time taken by impulses to travel between two points on a nerve.

Audiometer

This apparatus was designed to produce several fixed frequencies at different levels of intensity. It could either deliver the tone to a subject's ear or transmit sound oscillations to the skull. An experimenter would generally use an audiometer to find the auditory threshold of a subject. The data received from an audiometer is called an audiogram.

Colorimeters

These determine the color composition by measuring its tricolor characteristics or matching of a color sample. This type of device would be used in visual experiments.

Algesiometers and algometers

Both of these are mechanical stimulations of pain. They have a sharp needle-like stimulus point so it does not give the sensation of pressure. Experimenters use these when doing an experiment on analgesia.

Olfactometer

An olfactometer is any device that is used to measure the sense of smell. The most basic type in early studies was placing a subject in a room containing a specific measured amount of an odorous substance. More intricate devices involve some form of sniffing device, such as the neck of a bottle. The most common olfactometer found in psychology laboratories at one point was the Zwaardemker olfactometer. It had two glass nasal tubes projecting through a screen. One end would be inserted into a stimulus chamber, the other end is inserted directly into the nostrils.

Mazes

Probably one of the oldest instruments for studying memory would be the maze. The common goal is to get from point A to point B, however the mazes can vary in size and complexity. Two types of mazes commonly used with rats are the radial arm maze and the Morris water maze. The radial arm maze consists of multiple arms radiating from a central point. Each arm has a small piece of food at the end. The Morris water maze is meant to test spatial learning. It uses a large round pool of water that is made opaque. The rat must swim around until it finds the escape platform that is hidden from view just below the surface of the water.

Electroencephalograph (EEG)

The EEG is an instrument that can reflect the summed electrical activity of neural cell assemblies in the brain. It was originally used as an attempt to improve medical diagnoses. Later it became a key instrument to psychologists in examining brain activity and it remains a key instrument used in the field today.

Functional magnetic resonance imaging (fMRI)

The fMRI is an instrument that can detect changes in blood oxygen levels over time. The increase in blood oxygen levels shows where brain activity occurs. These are rather bulky and expensive instruments which are generally found in hospitals. They are most commonly used for cognitive experiments.

Positron emission tomography (PET)

PET is also used to look at brain activity. It can detect drugs binding neurotransmitter receptors in the brain. A down side to PET is that it requires radioisotopes to be injected into the body so the brain activity can be mapped out. The radioisotopes decay quickly so they do not accumulate in the body.

Eye tracking

Eye trackers are used to measure where someone is looking or how their eyes are moving relative to the head. Eye trackers are used in the study of visual perception and--because people typically direct their attention to the place they are looking--also to provide directly observable measures of attention.

Criticism

Frankfurt school

One school opposed to experimental psychology has been associated with the Frankfurt School, which calls its ideas "Critical Theory." Critical psychologists claim that experimental psychology approaches humans as entities independent of the cultural, economic, and historical context in which they exist. These contexts of human mental processes and behavior are neglected, according to critical psychologists, like Herbert Marcuse. In so doing, experimental psychologists paint an inaccurate portrait of human nature while lending tacit support to the prevailing social order, according to critical theorists like Theodor Adorno and Jürgen Habermas (in their essays in The Positivist Debate in German Sociology).

Experimental political science

From Wikipedia, the free encyclopedia

Experimental political science is the use of experiments, which may be natural or controlled, to implement the scientific method in political science.

History development and usage

In the 1909 American Political Science Association presidential address, A. Lawrence Lowell claimed: “We are limited by the impossibility of experiment. Politics is an observational, not an experimental science….” He argued that political science, as an emerging discipline, did not need to follow the experimental-led approach of the natural sciences. In the 1900s, observational research was the only way of doing research in political science.

The first experiment in political science is regarded to be Harold Gosnell's 1924 study on voter turnout in Chicago. In this experiment, he randomly assigned districts to receive information on voter registration and encouragement to vote.

In the 1950s, the behaviorist revolution was in full swing, and the development of experimental politics ushered in the first watershed.

The first experiment published in the American Political Science Review was in 1956, 50 years after the publication's inception. The American Political Science Review covered all fields of political science and was found by the Cambridge University Press in 1906. Another mainstream political science journal, the Journal of Conflict Resolution, also began publishing articles on experimental research during this period.

In the 1970s, with the rise of political psychology, the rejection of experimental politics softened.

In the 1980s, computer-assisted telephone interviewing began to appear and was used for the collection of experimental data—the advances in the technology led to the initial rise of experiments.

The period before 2000 was classified as the prelude to the experimental era. This is the long incubation stage of experimental politics. During this period, experimentation was not the main academic activity of political science. Many great discoveries come from the integration of scholars with using multiple methods.

From 2001 to 2009, this period was the first generation when experiments were widely used. Experimentation was becoming part of the political scientist's toolkit during this period due to the development of information technology.

From 2010 till now, we are in the new era of experimental political science 2.0.

Due to the development of the internet, the emergence of commercial internet survey panels and crowdsourcing platforms make data much cheaper and easier to obtain than ever before. Abundant and accessible information is the basis for the wider implementation of experiments in political science.

In 2010,  the Experimental Research section  of the American Political Science Association held its first conference.

In 2012, Bond et al.'s experiment delivered political mobilization messages to 61 million Facebook users. They aimed to explore whether an “I Voted” widget that announced one’s election participation to others increased turnout among Facebook users and their friends. Today's mature social media provide the opportunity to intervene experimentally with a vast capacity population.

In 2014, the first issue of the Journal of Experimental Political Science was published by the Experimental Research section  of the American Political Science Association.

From 2010 to 2019, there were 75 articles using experimental methods published in American Political Science Review. The figure was 76 from 1950 to 2009 in this journal.

Current experts in experimental methodology in political science include Rebecca Morton and Donald Green.

Among the areas that it is used in are:

What makes a good experiment?

Validity

Social scientists, including political scientists, have long used validity to measure whether a particular analytical method can provide credible evidence for validating theoretical inferences. Donald Campbel defines validity as the validity of an empirical research design or method as the degree of approximation between the knowledge inference based on the design or method and the actual situation. Alternatively, validity is the extent to which we can believe that the empirical inference can reflect the real laws of human society. This definition has been recognized by most scholars.

Validity can be further divided into internal validity and external validity. Campbell further refined the internal validity into three parts: constructive validity, causal validity, and statistical validity.

Classification of validity aims to facilitate researchers to describe and conduct research from different aspects. Validity itself is a holistic concept. Any single class cannot exist in isolation from other validity. For example, high construct validity means that the research design has a higher degree of fit with the theory being studied. This makes the relationship of causal variables more stable from the statistical perspective, which supports the improvement of statistical validity.

Internal validity is a prerequisite for external validity. If a reasonable estimate of the target group is not made, there is no point in extending relevant estimates to groups outside the target group.

Internal validity

Internal validity refers to the degree to which knowledge inferences based on empirical research approximate the actual attitudes or behavioural patterns of the target population.

Constructive validity

Construct validity involves the generality of empirical inferences and aims to evaluate whether a research design is a reasonable and targeted assessment of the target theory.

Causal validity

Causal validity is similar to the "identification problem" in economics, which examines whether an empirical design can effectively eliminate interference factors and provide accurate evidence for determining causal effects or mechanisms.

Statistical validity

Statistical validity refers to whether there is a significant and stable statistical relationship between the core causal factors of the study at the empirical level. The most common test of statistical validity is repeated testing of the same sample of the target population.

External validity

External validity refers to how empirical inferences apply to populations other than the target population.

Experimental designs

Laboratory experiment

Laboratory experiments place subjects in specific environments and examine how individuals make specific political decisions (such as voting, jury trials, and legislation). Laboratory experiments have stricter control over the experimental site and time, and the entire experimental process must be completed under the supervision and guidance of the researcher. Questionnaires are usually used to collect the subjects' personal information and experimental results.

Laboratory experiments are usually carried out in independent laboratories, reflecting the researcher's understanding and attitude towards the information contained in time and space. Laboratory experiments emphasize the control environment and other non-experimental elements to maximize the exclusion of interference factors and accurately measure the causal effects of researched factors. The laboratory itself does not refer to the specialized laboratory used in the natural sciences. Classrooms, activity rooms, or other independent spaces can be used as experimental places.

Conjoint survey

The conjoint survey experiment is a method for examining multidimensional preferences.

Lab-in-the-field experiment

At one extreme, "pure" laboratory experiments are carried out in environments that researchers highly control. Students are often a convenient sample in lab experiments because they are easy to participate in and able to follow the experimental instructions reliably. Natural experiments are the kind of design at another extreme. In natural experiments, participants are in the daily-live conditions, and they do not know they are being observed.

Lab-in-the-field experimental research is located in a continuous spectrum between the "pure" lab experiments and natural experiments. It is conducted in a diversified environment with various types of subjects. The following four types of research experiments are distinguished according to the type of research problem they solve.

Specific populations

The hypothesis may have to be tested by using specific populations. Or the researcher hopes to test if a result could be generalized to a broader or a representative, population.

Measurement

Lab procedures can be put into use in the measurement of the field. Risk aversion, time preference (patience), altruism, cooperation, competition, and in-group discrimination are the most common measures.

Recruiting the treated

This kind of lab-in-the-field experiment is for the circumstance that participants who have already been treated are being recruited. The experimenters are recruiting rather than implementing treatments.

Teaching

The purpose of the experimenter may be to teach the target population about the games by using a lab-in-the-field approach. Through this process, the experimenter could target a particular policy problem. The game could be the treatment in this circumstance.

Audit study

Audit studies are often used for measuring bias or discrimination. Audit studies are part of the constructure of a giant field experiment. This field experiment aims to measure the behaviour of participants in the field rather than to change it. In most cases, researchers use the ways like sending messages to measure participants' behaviours unobtrusively.

Ethics

Experimental research methods in political science have unavoidable ethical questions: Can humans be used for experiments? While experiments in political science usually do not cause physical harm, the elements of deception is commonly existing.

When conducting political science experiments, researchers must intervene in the process of data generation. Political science, as social science, studies human behaviour. Then political science experiments will inevitably have an impact on people. For example, subjects in experiments make choices they would not otherwise face, or subjects are put into experiences or controls that they would not otherwise have.

The experimental process itself is not the only way political science research activities affect human life. Other influences include the influence of the dissemination of experimental results, the influence of political science scholars on their students, and the influence of research results on institutions and professional organizations. Just like the ethics of most other professions, political scientists have ethics.

In 1967, a committee was created by the American Political Science Association (APSA), which aims to explore issues “relevant to the problems of maintaining a high sense of professional standards and responsibilities.” Marver H. Bernstein served as the chairman of this committee. This committee created the first version of the written code of rules of professional conduct.

In 1968, Standing Committee on Professional Ethics was founded. Their job mainly includes the review of formal grievances, mediation and intermediation to other organizations, and issuing formal advisory opinions.

In 1989 and 2008, the code of rules of professional conduct was revised.

Ways ahead in experimental political science

After the 1970s, most political scholars began to use experimental methods to focus their research on political behaviour, public opinion, and mass communication. The classic topics include exploring the behavioural preferences and choices of different social groups in group actions, the influence of campaign propaganda on voting results in the voting process, the influence of media propaganda on public attitudes, and the influence of personality on political participation.

Since the beginning of the 21st century, political science research has clearly shown a trend from correlation research to causality research. Political scientists are increasingly dissatisfied with just confirming the strength of the relationship between various factors, and gradually devote themselves to the discussion of causal effects and mechanisms among variables. To measure causal effects accurately is a significant problem and challenge in the social sciences. The means to keep inferences from selection bias in observational studies are minimal. In experimental research, randomly assigning the observation objects to the experimental group and the control group can ensure that there are no observable or unobservable differences between the research objects in theory before the practical operation. The objectivity of the conclusion is built on randomization in this way.

The inherent flaws of various non-experimental study methods have been continuously exposed in the past 20 years. The most notable drawback among all is the limitation of observable data, which hinders researchers' further exploration of causality. In a modern society with highly developed information technology, it is becoming more and more efficient and low-cost to control and collect data by conducting experiments.

The emergence of new communication methods and new media is both a challenge and an opportunity for social science research. These social media and online blogs transmit a large amount of political information and make it more accessible to the public. In the past, the information for social science research was generally insufficient and deficient. Now it is necessary to face the problem of screening the validity of information in the era of information explosion.

Current political scientists are more and more inclined to explore political behaviour's psychological basis and attitude characteristics through experimental means. The distinctive feature of current research is that it focuses on some specific social groups, such as unmarried people, students, ethnic minorities, etc. Investigations about the general population are insufficient.

Different research methods have distinct advantages and disadvantages. The disadvantages of one method cannot be compared with the advantages of another method. More and more scholars have begun to use a mixture of different methods to make up for the shortcomings of a single experimental approach. In the field of social sciences, experimental research methods need to be combined with other research methods to obtain knowledge innovation in both theory and methodology and promote the development of the discipline.

United States labor law

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