History of Psychology 2008

History of Psychology 2008 Lecture 9 Professor Cupchik Office: S634 Email: cupchik@utsc.utoronto.ca Office hours: Wed 1-2; Thurs 12-1 Course website: www.utsc.utoronto.ca/~cupchik TA: Michelle Hilscher Office: S142C Email: hilscher@utsc.utoronto.ca Office hours: Wed 12-2 pm Textbook: Benjafield’s History of Psychology

“The Emergence of Experimental Psychology” Where does psychology stand in the 1870s? Physiology and reaction time in astronomy shows that it takes time for a stimulus to register within the nervous system and for a response or movement to occur. So we can ask about the delays in different parts of the nervous system: 1. Sense organ and peripheral nerves 2. Brain reaction and motor nerves 3. Motor nerves and muscles

And how much time does it take to recognize, recall, decide, choose, judge or execute different mental processes? • Experimental psychology was growing up spontaneously within experimental physiology (problems, methods and techniques). • Psychology was the description and analysis of the contents of consciousness. Consciousness depended on sensations and images from the senses as its basic materials. • There was clearly a relation of mental states and acts as revealed by introspection and the sensory process and brain function studied in experimental physiology. • The psychological interest in describing “sensations” as the basic contents of mind could be made more exact by applying the methodology of experimental physiology and psychology. • This could replace arm chair introspection as the source of knowledge for contents and operations of the conscious mind. • The immediate task was to isolate and measure the dimensions of sensation.

Gustav Fechner (1801-1887) He was the son of a poor Lutheran pastor who was very open to new scientific ideas and died when Gustav was just 5 years old. His father attached a lightening rod to the church steeple which was seen as a lack of faith by the parishioners. Fechner was trained in medicine but turned to physiology and math. He lived by translating French science books into German (9000 pages). He had a severe breakdown possibly from overwork. He also injured his eyes from gazing at the sun through coloured glasses and this coincided with a psychological disorder. He lived as a hermit in a darkened room for 3 years and could not concentrate or control his attention and thinking. He became deeply religious and this led him to attack materialism and to explore the ultimate nature of the soul.

Fechner sought to prove that physical aspects of the world are fictions and that mental events are the sole reality. Ironically, he found a way to make experience concretely measurable. He spent 9 intensive years working on the problem and the result was the development of statistical and experimental techniques which were rigorous and could measure psychological variables such as the subjective experience of sensation. This was based on the work of his Leipzig colleague Weber who studied the human capacity to make accurate discriminations. He noticed that if we try to compare, for example, two lines of almost equal length, we often fail to notice any difference. The smallest (i.e., “just”) noticeable difference (JND) is 1/50th the length of the length of one of the two lines. Fechner wanted to scale sensory experience. In other words, by how many degrees is one sensation greater than another? (e.g., two trumpets are not necessarily twice as loud as one).

Perhaps the intensity of a sensation (brightness or loudness) increases, not proportionally to the intensity of a source, but more slowly. So an arithmetic increase in mental intensities may correspond to a geometric increase of physical energies. He devised three experimental techniques using Weber and Herbart’s idea of a “limen” or “threshold” between the: (1) “Absolute threshold” or measurable intensity of a stimulus needed for a sensation to occur at all and the (2) “differential threshold” or amount by which a stimulus must increase in intensity for a person to perceive a change. The strategy was to measure the degree to which an increase in sensation is less than an increase in the stimulus.

Method of Limits – Change a stimulus by discrete measured steps until the subject reports a change in intensity of the experienced sensation. The scale of the stimulus is the number of j.n.d.s that sensation is above 0, the value of the limen. Before Fechner, sensations were items in the stream of consciousness open to vague introspection and describable only in terms of words from everyday speech. Now they were reactions capable of objective investigation and indirect measurement. As a consequence, psychology could become an experimental and quantifiable science. An environmental variable related to behaviour was isolated and manipulated by the experimenter and its attributes were indirectly measured. Changes in the stimulus could be correlated with changes in a response dimension. Fechner also established the study of experimental aesthetics.

Hermann Von Helmholtz (1821-1894) was one of the greatest 19th century scientists. His primary field was physics, optics and acoustics. Pure science offered few possibilities for a career and so he chose medicine. He built his reputation in physiology. In 1850, he measured the speed of the nervous impulse. As a consequence, sensation, thought and movement follow each other and do not occur simultaneously. This led to experiments on reaction time. The subject reacts to a specific stimulus by a sign or movement making possible the indirect investigation of intervening processes. In 1851, he invented the ophthalmoscope to examine people’s eyes. He developed a theory of colour vision… three receptor mechanisms in the eye give rise to red, green and blue which combine to produce all colours.

Helmholtz developed the Doctrine of Unconscious Inference which holds that when we perceive our conscious experience contains much that is not either in the stimulus situation or a contribution of receptor mechanisms. Past experience is unconsciously added to the total reaction. Central processes “interpret” or “process” the information to produce a finished perception. For example, in stereoscopic vision – a geometer can estimate depth or distant objects but in perception these estimates are instant. In other words, we construct events based on experience. He strongly opposed nativistic (i.e., innate) doctrines (such as Kant’s position on innate disposition to space perception) and handed this view over to the Leipzig School. Sensation was prior to unconscious inference and perception was dependent upon it.

Wilhelm Wundt & the Leipzig School (1832-1920) He was the first experimental psychologist. He left 500 works, established the first lab designed to study psychological problems in Leipzig (1879) and trained the first PhDs in psychology. He also established the first journal in psychology (Philosophishe Studien) to publish papers based on research in his lab. He was the only child of a Lutheran pastor. He led a quiet and studious life as a boy. He was described as humourless, indefatigable, and aggressive. He also studied medicine but was drawn to physiology. He spent 13 years at Heidelberg before taking a professorship in Leipzig in 1875.

He developed a systematic approach to method and experimental research but he also had a strong interest in “cultural” psychology related to language and myth. Based on his approach, psychology became the study of immediate experience involving the analysis of conscious processes into elements and the determination of their manner of connection. We have different modes of sensation (vision, audition, olfaction) and these modes have attributes along dimensions such as intensity, duration and extension. Analytical introspection of these elements of experience involved presenting a controllable and measurable stimulus to a subject under conditions known to the experimenter and a response is observed or reported. The introspection of events between S and R is done. Scientific instruments made the reporting of mental states and observation of responses more accurate. The Berlin School - It is important to emphasize the controversy between the associationists and their German experimentalist followers like Wundt and the forerunners of the Gestalt school.

Franz Brentano (1838-1917) and Carl Stumpf (1848-1936) Brentano attacked the empiricist view that consciousness may be analyzed into contents like sensations, feelings, and images as the basic elements of experience. Instead, mental acts should be the fundamental category. Although we experience sensations, what is fundamental is the activity of seeing colours, shapes and objects, hearing sounds and feelings ourselves moving. The activity of the mind in judging, sensing, imagining, remembering, and so on, is the true object of psychological study. The mind is creative and interpretive – this is the beginning of humanistic psychology.

Wilhelm Dilthey (1833-1911) was a German historian, psychologist, student of hermeneutics, and philosopher. Dilthey could be considered an empiricist, in contrast to the idealism common in Germany at the time, but his empirical work differs from British empiricism in its central epistemological assumptions, drawn from the German tradition from Kant onwards. Dilthey was inspired by the work of Friedrich Schleiermacher on hermeneutics, which had been neglected. Both philosophers are linked to German Romanticism. The school of Romantic hermeneutics stressed that an interpreter – not necessarily a Cartesian subject – could use insight, combined with cultural and historical context, to bring about truer understanding of a text.

Dilthey called the process of inquiry Schleiermacher had founded 'the Hermeneutic circle'. The "general hermeneutics" that Schleiermacher proposed was a combination of the hermeneutics used to interpret Sacred Scriptures (e.g. the Pauline epistles) and the hermeneutics used by Classicists (e.g. Plato's philosophy). Dilthey saw its relevance for the human sciences (Geisteswissenschaften) in particular, as opposed to the natural sciences. Dilthey's work influenced Martin Heidegger's approach to hermeneutics in Being and Time, though Heidegger more thoroughly 'temporalized' the possibilities of interpretation.

Dilthey was very interested in what we would call sociology today, although he strongly objected to being labelled a sociologist because the sociology of his day was mainly that of Auguste Comte and Herbert Spencer. He objected to their evolutionist assumptions about the necessary changes that all societal formations must go through, as well as their narrowly natural-scientific methodology. Also, the word tended (and tends) to be used as a kind of umbrella term; since the term sociology covered so much it had little analytical clarity. Comte's idea of Positivism was, according to Dilthey, one-sided and misleading. He did, however, have good things to say about his colleague Georg Simmel's versions of sociology. (Simmel was a colleague at the University of Berlin and Dilthey admired his work even though many academics were opposed to Simmel altogether, in part owing to anti-Semitism and in part because Simmel did not conform to the academic formalities of the day in some of his published work.)

Distinction between natural science and "human" science: A life-long concern was to establish a proper theoretical and methodological foundation for the 'human sciences' (e.g. history, law, literary criticism), distinct from, but equally 'scientific' as, the 'natural sciences' (e.g. physics, chemistry). He suggested that all human experience divides naturally into two parts: that of the surrounding natural world, in which "objective necessity" rules, and that of inner experience, characterized by "sovereignty of the will, responsibility for actions, a capacity to subject everything to thinking and to resist everything within the fortress of freedom of his/her own person".

Dilthey strongly rejected using a model formed exclusively from the natural sciences (Naturwissenschaften), and instead proposed developing a separate model for the human sciences (Geisteswissenschaften). His argument centered around the idea that in the natural sciences we seek to explain phenomena in terms of cause and effect, or the general and the particular; in contrast, in the human sciences, we seek to understand in terms of the relations of the part and the whole. (In the social sciences we may also combine the two approaches, a point stressed by Max Weber.) His principles, a general theory of Understanding (Verstehen) could, he asserted, be applied to all manner of interpretation ranging from ancient texts to art work, religious works, and even law. His interpretation of different theories of aesthetics in the seventeenth, eighteenth, and nineteenth centuries was preliminary to his speculations concerning the form aesthetic theory would take in the twentieth century.

Oswald Külpe (1862-1913) and the Würzburg School Külpeand his associates further demonstrated the limitations of the empiricist emphasis on the contents of consciousness. One student showed that in judging which of two weights was the heavier, no sensory or imaginal contents occurred in the judgment process. Vague attitudes passed through consciousness (e.g., hesitation or doubt). But the answer did not result from comparing images of the two reaction in weighing. In sum, research in both Külpe’s lab and in France (Binet) and America (Woodworth) showed that in judgment and cognitive tasks subjects reported that important aspects of the process did not yield or were not based upon a comparison of sensory images. This led to an emphasis on non-sensory character of many items in consciousness during cognitive tasks. We have thought elements that do not belong to the same category as sensations or image. This led to the idea of “imageless thought” was based on processes that Wundt and Helmholtz failed to discriminate.

The Würzburg School convinced many that the conditions which influence our behaviour in thinking and choice are not present in consciousness. Wundt and his students fought back. For example, Titchener repeated many of the Würzburg experiments and found sensory contents of the kind that fit his associationist theory. But this dispute, in which introspection under lab conditions failed to produce agreement about the data observed, led many to regard introspection as a weak technique. Behaviourism By emphasizing that little occurred between the stimulus and the reaction in their experiments, the Würzburg School shifted the emphasis from the contents of consciousness to conduct or response. Their theory that much goes on below the threshold of consciousness reinforced psychoanalytic ideas but also set the stage for behaviourism.

Charles Darwin and the Evolutionary Doctrine (1809-1882) In 1859 Darwin published The Origin of Species by Natural Selection. While the evolutionary concept existed long before Darwin, he was the first to popularize it and introduce evidence for it. Influences: (1) He was influenced by Lyell’s Principles of Geology (1830-1833) in which it was argued that the strata of rock found in the earth’s crust had been formed through a long history of physical crisis. This suggested to Darwin that organic matter might also have evolved from simple to complex forms through a succession of historical changes over a long period of time.

During 1831-36 he voyaged on a scientific expedition to the South Seas on the Beagle. His observation of a wide variety of species in the isolated set of islands led him to wonder whey each species of plant and animal is so perfectly adapted to the conditions of the environment. He also noticed that out of every generation of species some survive and reproduce while others die before hand. What principle governs the selection of species?

(2) In 1838 he read Malthus’s Essay on the Principles of Population (1798). Malthus felt that a portion of the population must die to leave sufficient food for the survivors. Disease, infant mortality, starvation and war keep the balance of population and food. There is a struggle for the control of the means of subsistence in which the stronger survive at the expense of the weak. This led Darwin to the hypothesis that “favourable variation would tend to be preserved and unfavourable ones destroyed. The result would be the formation of a new species.”

Three Basic Principles in Darwin’s Theory of Evolution 1. Variation: i. The number of species vary among themselves. ii. Variations survive only if they are well adjusted to the environment. 2. Struggle for Existence: Due to the fact that plants and animals produce more offspring than can survive there is competition for the means of subsistence between: i. Individual versus individual ii. Species versus species iii. Living thing versus the environment 3. Natural Selection: Any being, if it varies in a manner profitable to itself will survive and will be ‘naturally selected’. He felt there were influences in nature analogous to artificial selection by humans in breeding domestic animals with special qualities. Human breeders do no initiate variations but strengthen desirable variation which exists.

His next work The Descent of Man (1871) was a blow to man’s ego. Humans were descended from ape-like ancestors which implies that man’s intellectual powers were different only in degree and not in kind from certain vertebrates. The public was shocked at the open contradiction of the doctrine that man had been specifically created by G-d and many feared the consequences for society of this “lowering” of the human status.

He also wrote a classic work, The Expression of the Emotions in Man and Animals (1872) which was empirical and descriptive without being experimental. It involved an application of the method of field studies in the natural history of psychology. He collected observations and categorized the sounds emitted by various animals in situations where general reactions such as fear or sexual excitement are dominant. He also looked at human vocalization during emotional reactions and noted how variations in loudness and pitch were associated with expressions of particular emotions.

Darwin concluded that physical responses were specific to certain situations and often there was a direct comparison between human and animal expressive signs. He used data from psychiatrists reporting about mental patients and from explorers who provided anthropological information about “primitive people” (i.e., a racist reference to people from small scale societies). He also carried out observation of his own children on typical infant reactions (his wife did this) such as screaming when hungry or frustrated. He also used photographs he took of a variety of subjects reacting emotionally or actor following instructions to express particular emotions. He then gave minute descriptions of facial expressions, bodily tension and posture during emotional expression. His conclusion was that physical reactions must be innate and inherited.

What is the importance of Darwin to Psychology? He presented an entirely new approach to the subject matter of psychology. 1. He made observable factors the primary data (overt behaviour) because him main interest was in observing and describing behaviour. As a consequence, the approach of a zoologist was extended to human and animal psychology. 2. His approach to his data was genetic or developmental. He explained any characteristic behaviour by showing how it originated in the individual or species and traced how it developed under the influence of the environment to its present form. This historically oriented approach is now established in clinical and developmental psychology.

3. In contrast to Locke’s tabula rasa, Darwin emphasized heredity so that much of importance in human nature is passed on from parent to offspring. This initiated the nature versus nurture controversy in modern psychology. How much of our behaviour is organized by genetic and constitutional factors and how much from learning? Darwin believed that both were important but that heredity was neglected. 4. Relating to environmental factors, he introduced the broad concepts of: i. Adjustment ii. Adaptation This approach conceives of human beings as dynamic and actively striving to meet problems of the physical and social environment.

Darwin also considered the role of success or failure in adjustment. The older psychology viewed humans as self-conscious and introspective beings who interpret experience in terms of reason and sentiment. So the mind or field of consciousness was removed from the outer world of which it had only indirect and imperfect knowledge. Darwin introduced the concept of humans as striving through actions toward specific goals determined by interaction with the environment.

The new questions in psychology became: How are habits and skills learned? What factors motivate behaviour? In what ways are humans different from each other in their capacity to adjust and why? Darwin’s general theory made the study of behaviour an important part of psychology. Question: In what respect do animals have similar behavioural capacities to humans? Intelligence? This led to the field of comparative psychology. Man could no longer be studied as an isolated phenomenon, a superior mind cut off from the rest of nature.

Darwin drew attention to variations within species that are crucial to survival. This led to the idea that individual humans vary along specific dimensions — general ability, specific aptitudes, character, and ‘stability’ of temperament. The older psychology was interested in generalizations which applied to all humans. Darwin introduced new questions about individuals. This characterized the distinction between idiographic and nomothetic approaches to psychology.

The Rise of American Psychology

Sir Francis Galton (1822-1911) - Wealthy half-cousin of Darwin and was both a geographer and explorer (Africa). - He was also interested in meteorology and produced the first weather maps of the British Isles. - As a result of his extensive travel, his interests turned toward anthropology. - He observed differences between (1) cultural groups and (2) people within a culture. - His goal was to evaluate individual differences among people using precise measurements. - This was the start of the field of psychometrics which is defined as the application of statistics to measure individual differences with reference to behavioural variables.

Beyond the special skills recognized by the faculty psychology of the times (music, math, athletic skills), Galton insisted on a primary general intellectual ability that he believed was inherited. This implied that: (1) behavioural and mental traits could be inherited and (2) differences between individuals could be measured. He offered the following proof for his argument: He selected men of outstanding ability and looked at the frequency of success among their relatives. i. 31% had illustrious fathers ii. 48% had eminent sons He concluded that outstanding ability is inherited.

Problem: Galton used a restricted sample. In Victorian England selection for professions depended on connections and this applied both to education and entry to key jobs. Note that Galton did not include either women or successful businessmen from industry and commerce. So: He over emphasized hereditary factors and under emphasized environmental factors. Also, elementary education was only made compulsory in 1880 by the Liberal Party in England.

In 1884, at an International Health Exhibition in London, Galton introduced an Anthropometric Lab with equipment of his own invention where he started mental testing and collected individual difference data of diverse attributes: 1. Body measurement and muscular strength 2. Sensory capacities such as the ability to discriminate between different intervals of pitch 3. Reaction time Galton’s Lab

Galton had a young American assistant, J.M. Cattell, who had studied with Wundt and he carried Galton’s work to the USA in 1888. Cattell carried out extensive pioneer work on mental tests and one of his pupils, E.L. Thorndike, was a major test developer. So Galton was the source of the American testing movement. Summary of his contributions: 1. Correlations 2. Rating scales 3. Questionnaires 4. Use of the normal curve 5. Mental tests

COMPARATIVE PSYCHOLOGY Darwin had directed people’s attention to the problem of explaining animal behaviour (e.g., how do animals adjust to their environment?) Descartes had viewed animals as complicated automatons. But, do animals have the capacities for learning new habits? Do they vary in intelligence? How do they compare with humans? The British started the field of comparative psychology which considers animals in relation to humans.

Douglas Spalding (1840-1877) 1. He demonstrated instinctual behaviour in small chicks who reacted defensively by flying away and hiding upon first being shown a hawk. This innate fleeing response was independent of learning or imitation. 2. He also demonstrated imprinting. Very soon after emerging from the egg, chicks demonstrated a following response for objects or even humans. G.J. Romanes (1849-1899) He combined the experimental method with systematic theory. He regarded adjustment as dependent on the ability to discriminate and classify stimulus from the senses.

Lloyd Morgan (1852-1936) He provided the classic cannon for research in animal behaviour. “In no case can we interpret an action as the outcome of the higher faculty, if it can be interpreted as the outcome of the exercise of one which stands lower in the psychological scale.” So careful observation either under (1) experimental circumstances or (2) in the field, were the only acceptable data. It is essential to avoid any form of anthropomorphism which is attributing human traits to animals. He distinguished between innate and acquired behaviour. He formally defined instincts which are an aspect of innate behaviour. (1) Common to all members of a species (2) Fairly uniform and repetitive in nature (3) Made in response to a specific stimulus (4) Have a clear connection with the anatomical structure and physiological functioning of the animal

Morgan disagreed with any implications of mysterious “inner powers” or unknown neural mechanisms. He laid the foundation for later work on animal learning. He used the terms: (1) “trial and error” to describe how responses which do not achieve the end required are dropped from the sequence. (2) “reinforcement” of successful modes of response through the pleasure-pain mechanism. So: (1) He introduced many of the ideas underlying behaviourism and (2) used the word behaviour to indicate the main data of psychological research. Darwin and his followers, through their observation of phenomena, emphasis on behaviour and openness to new ideas, had a strong influence on the development of psychology in the USA.

PSYCHOLOGY IN THE USA The earliest teaching of psychology in the USA was undertaken by philosophers who adhered to the beliefs of the Scottish School and used the texts of Thomas Brown and Thomas Reid. A distinctive tradition emerged in the USA which broke free from British Empiricism in theory and German experimentalism in method, resembling more closely Galton and Darwin. American psychology dealt with the mind in use - a pragmatic and functional approach. By 1910, the earliest American psychology included: (1) experimental human, (2) experimental animal, and (3) mental tests, and they were becoming aware of Freud. It may be noted that the first lab in Canada was established at the University of Toronto in 1890 by Alfred Baldwin.

Why did American psychology deviate from the German pattern? Many had travelled to Leipzig to learn from Wundt and were enthusiastic about the experimental method and laboratory techniques. But ultimately they evolved from a description of the generalized mind to the assessment of personal abilities in the successful adjustment of the individual to the environment. The determining factor was the American adoption of ideas about evolution. But why then did the English lag behind the Americans? The answer is that America was ready for ideas about evolution because it was a pioneer country and the strong pioneer would be the only person able to survive. This stress on individualism pushed the philosophy of pragmatisim (do what works) and functionalism (what works, is!). From the perspective of pragmatism the validation of any knowledge must be in terms of its consequences, values and utility.

This represents a modern form of the sources of change present in the Renaissance. (1) forces against hereditary right and for the recognition of personal achievement. (2) forces against theological dogma and for scientific inquiry (3) forces reinforced by the discovery of new land and wealth in the New World and Far East.

THE AMERICAN SCHOOL OF FUNCTIONALISM What and why did the functionalist movement grow up in America? How was it replaced by behaviourism? Definition: What is a functionalist psychology? According to Woodworth (1948), “A psychology that attempts to give an accurate and systematic answer to the question “What do men do?” and “Why do they do it?” More specifically, it is concerned with the function of an organism’s behaviour and consciousness in its adaptation to its environment. So a concern is displayed for the utility of consciousness and behaviour.

William James (1842-1910) He was the father of American psychology. He was an intellectual force who demonstrated that there is a science of psychology and illustrated its scope and method. He came from a wealthy and gifted family. Henry James, the novelist, was his brother. He set up a laboratory at Harvard University in 1875-76 and taught the relations of physiology and psychology. Major contributions: (1) He opposed the rigidity and narrowness of Wundt’s German experimentalism. (2) He sketched out fruitful lines of development which pointed ahead to the two American movements of functionalism and behaviourism.

(3) He laid the foundation for individual psychology typical of personality and clinical psychology (as distinct from psychometrics). (4) He made the biological sciences the main foundation and model for psychology. William James’ Approach Approached materials free from the straight jacket of sophisticated theories or questions based on technical jargon. He avoided structuring raw data in terms of hidden assumptions. Wundt, for example, pressed his data into an elaborate framework constructed to conform to abstract and fashionable canons of “scientific method”. James’ desire to view data as raw and unprocessed reflected the biological scientist’s insight that a natural history phase precedes a more sophisticated laboratory experiment phase in the development of life sciences.

As psychology was just beginning, James wanted simple description and classification of basic facts together with the definition of crucial problems. This attitude determined (1) the wide variety of data in his books and (2) his freedom from the philosophical theories behind British Empiricism and German experimentalism. So James collected a wide variety of empirical data including experimental results, anthropology and clinical reports, physiological and zoological knowledge. This directed his thinking toward: (1) defining the problems that arise directly from such interrelated data. (2) showing what are the gaps in empirical evidence related to a specific problem and (3) suggesting what sort of data are relevant toward filling them in He always avoided unobservable operations or processes which cannot be even indirectly tested. He stuck close to his facts. Discipline versus Problem Orientation.

He disposed of all fashionable theories about the nature of the “mind” as irrelevant to psychology and argued that “there is an unmediated correspondence between the succession of states in consciousness with the succession of total brain processes.” This affirmed the biological nature of psychology. He studied the purpose of consciousness (its biological use). Conscious choice versus habit. Consciousness becomes involved when there is a new problem and a need for a new adjustment. So, in sum, he treats psychology as a natural science concerned with the living organism as it strives to adjust to its environment.

Psychological functions are refinements of basic biological functions. Mental life is a biological function which enables man to adjust to the environment. He distinguished: (1) peripheral sensory system (2) perceptual organization of sensory stimuli (afferent process) (3) cognitive function as the refinement of perceptual organization (4) movement, the afferent process, is a basis for the treatment of instinct, emotion and voluntary action. Note also the ideomotor theory whereby sensory and ideational processes spontaneously express themselves in action unless inhibited.

History of Psychology 2008