This article is a general timeline of psychology.
Ancient history – BCE c. 1550 BCE – The Ebers Papyrus mentioned depression and thought disorders. c. 600 BCE – Many cities in Greece had temples to Asklepios that provided cures for psychosomatic illnesses. 540–475 Heraclitus c. 500 Alcmaeon – suggested theory of humors as regulating human behavior (similar to Empedocles' elements) 500–428 Anaxagoras 490–430 Empedocles proposed a first natural, non-religious system of factors that create things around, including human characters. In his model he used four elements (water, fire, earth, air) and four seasons to derive diversity of natural systems. 490–421 Protagoras 470–399 Socrates – Socrates has been called the father of western philosophy, if only via his influence on Plato and Aristotle. Socrates made a major contribution to pedagogy via his dialectical method and to epistemology via his definition of true knowledge as true belief buttressed by some rational justification. 470–370 Democritus – Democritus distinguished between insufficient knowledge gained through the senses and legitimate knowledge gained through the intellect—an early stance on epistemology. 460 BC – 370 BCE – Hippocrates introduced principles of scientific medicine based upon naturalistic observation and logic, and denied the influence of spirits and demons in diseases. Introduced the concept of "temperamentum"("mixture", i.e. 4 temperament types based on a ratio between chemical bodily systems. Hippocrates was among the first physicians to argue that brain, and not the heart is the organ of psychic processes. 387 BCE – Plato suggested that the brain is the seat of mental processes. Plato's view of the "soul" (self) is that the body exists to serve the soul: "God created the soul before the body and gave it precedence both in time and value, and made it the dominating and controlling partner." from Timaeus c. 350 BCE – Aristotle wrote on the psuchê (soul) in De Anima, first mentioning the tabula rasa concept of the mind. c. 340 BCE – Praxagoras 371–288 Theophrastus 341–270 Epicurus c. 320 Herophilus c. 300–30 Zeno of Citium taught the philosophy of Stoicism, involving logic and ethics. In logic, he distinguished between imperfect knowledge offered by the senses and superior knowledge offered by reason. In ethics, he taught that virtue lay in reason and vice in rejection of reason. Stoicism inspired Aaron Beck to introduce cognitive behavioral therapy in the 1970s. 304–250 Erasistratus 123–43 BCE – Themison of Laodicea was a pupil of Asclepiades of Bithynia and founded a school of medical thought known as "methodism." He was criticized by Soranus for his cruel handling of mental patients. Among his prescriptions were darkness, restraint by chains, and deprivation of food and drink. Juvenal satirized him and suggested that he killed more patients than he cured. c. 100 BCE – The Dead Sea Scrolls noted the division of human nature into two temperaments.
1st–5th century CE c. 50 – Aulus Cornelius Celsus died, leaving De Medicina, a medical encyclopedia; Book 3 covers mental diseases. The term insania, insanity, was first used by him. The methods of treatment included bleeding, frightening the patient, emetics, enemas, total darkness, and decoctions of poppy or henbane, and pleasant ones such as music therapy, travel, sport, reading aloud, and massage. He was aware of the importance of the doctor-patient relationship. c. 100 – Rufus of Ephesus believed that the nervous system was instrumental in voluntary movement and sensation. He discovered the optic chiasma by anatomical studies of the brain. He stressed taking a history of both physical and mental disorders. He gave a detailed account of melancholia, and was quoted by Galen. 93–138 – Soranus of Ephesus advised kind treatment in healthy and comfortable conditions, including light, warm rooms. c. 130–200 – Galen "was schooled in all the psychological systems of the day: Platonic, Aristotelian, Stoic, and Epicurean" He advanced medicine by offering anatomic investigations and was a skilled physician. Galen developed further the theory of temperaments suggested by Hippocrates, that people's characters were determined by the balance among four bodily substances. He also distinguished sensory from motor nerves and showed that the brain controls the muscles. c. 150–200 – Aretaeus of Cappadocia 155–220 Tertullian 205–270 Plotinus wrote Enneads a systematic account of Neoplatonist philosophy, also nature of visual perception and how memory might work. c. 323–403 – Oribasius compiled medical writings based on the works of Aristotle, Asclepiades, and Soranus of Ephesus, and wrote on melancholia in Galenic terms. 345–399 – Evagrius Ponticus described a rigorous way of introspection within the early Christian monastic tradition. Through introspection, monks could acquire self-knowledge and control their stream of thought which signified potentially demonic influences. Ponticus developed this view in Praktikos, his guide to ascetic life. c. 390 – Nemesius wrote De Natura Hominis (On Human Nature); large sections were incorporated in Saint John Damascene's De Fide Orthodoxia in the eighth century. Nemesius' book De Placitis Hippocratis et Platonis (On the Doctrines of Hippocrates and Plato) contains many passages concerning Galen's anatomy and physiology, believing that different cavities of the brain were responsible for different functions. 397–398 – St. Augustine of Hippo published Confessions, which anticipated Freud by near-discovery of the subconscious. Augustine's most complete account of the soul is in De Quantitate Animae (The Greatness of the Soul). The work assumes a Platonic model of the soul. 5th century – Caelius Aurelianus opposed harsh methods of handling the insane, and advocated humane treatment. c. 423–529 – Theodosius the Cenobiarch founded a monastery at Kathismus, near Bethlehem. Three hospitals were built by the side of the monastery: one for the sick, one for the aged, and one for the insane. c. 451 – Patriarch Nestorius of Constantinople: his followers dedicated themselves to the sick and became physicians of great repute. They brought the works of Hippocrates, Aristotle, and Galen, and influenced the approach to physical and mental disorders in Persia and Arabia
6th–10th century 625–690 – Paul of Aegina suggested that hysteria should be treated by ligature of the limbs, and mania by tying the patient to a mattress placed inside a wicker basket and suspended from the ceiling. He also recommended baths, wine, special diets, and sedatives for the mentally ill. He described the following mental disorders: phrenitis, delirium, lethargus, melancholia, mania, incubus, lycanthropy, and epilepsy c. 800 – The first bimaristan was built in Baghdad. By the 13th century, bimaristans grew into hospitals with specialized wards, including wards for mentally ill patients. c. 850 – Ali ibn Sahl Rabban al-Tabari wrote a work emphasizing the need for psychotherapy. c. 900 – Ahmed ibn Sahl al-Balkhi urged doctors to ensure that they evaluated the state of both their patients' bodies and souls, and highlighted the link between spiritual or mental health and overall health. c. 900 – al-Razi (Rhazes) promoted psychotherapy and an understanding attitude towards those with psychological distress.
11th–15th century 1025 – In The Canon of Medicine, Avicenna described a number of conditions, including hallucination, insomnia, mania, nightmare, melancholia, dementia, epilepsy, paralysis, stroke, vertigo and tremor. c. 1030 – Al-Biruni employed an experimental method in examining the concept of reaction time. c. 1180 – 1245 Alexander of Hales c. 1190 – 1249 William of Auvergne c. 1200 – Maimonides wrote about neuropsychiatric disorders, and described rabies and belladonna intoxication. 1215–1277 Peter Juliani taught in the medical faculty of the University of Siena, and wrote on medical, philosophical and psychological topics. He was personal physician to Pope Gregory X and later became archbishop and cardinal. He was elected pope under the name John XXI in 1276. c. 1214 – 1294 Roger Bacon advocated for empirical methods and wrote on optics, visual perception, and linguistics. 1221–1274 Bonaventure 1193–1280 Albertus Magnus 1225 – Thomas Aquinas 1240 – Bartholomeus Anglicus published De Proprietatibus Rerum, which included a dissertation on the brain, recognizing that mental disorders can have a physical or psychological cause. 1247 – Bethlehem Royal Hospital in Bishopsgate outside the wall of London, one of the most famous old psychiatric hospitals was founded as a priory of the Order of St. Mary of Bethlem to collect alms for Crusaders; after the English government secularized it, it started admitting mental patients by 1377 (c. 1403), becoming known as Bedlam Hospital; in 1547 it was acquired by the City of London, operating until 1948; it is now part of the British NHS Foundation Trust. 1266–1308 Duns Scotus c. 1270 – Witelo wrote Perspectiva, a work on optics containing speculations on psychology, nearly discovering the subconscious. 1295 Lanfranc of Milan writes Science of Cirurgie 1317–1340 – William of Ockham, an English Franciscan friar and scholastic philosopher and theologian, is commonly known for Occam's razor, the methodological principle that the simplest explanation is to be preferred. He also produced significant works on logic, physics, and theology, advancing his thoughts about intuitive and abstracted knowledge. c. 1375 – English authorities regarded mental illness as demonic possession, treating it with exorcism and torture. c. 1400 – Renaissance Humanism caused a reawakening of ancient knowledge of science and medicine. 1433–1499 Marsilio Ficino was a renowned figure of the Italian Renaissance, a Neoplatonist humanist, a translator of Greek philosophical writing, and the most influential exponent of Platonism in Italy in the fifteenth century. c. 1450 – The pendulum in Europe swings, bringing witch mania, causing thousands of women to be executed for witchcraft until the late 17th century.
16th century 1590 – Scholastic philosopher Rudolph Goclenius coined the term "psychology"; though usually regarded as the origin of the term, there is evidence that it was used at least six decades earlier by Marko Marulić.
17th century c. 1600–1625 – Francis Bacon was an English philosopher, statesman, scientist, lawyer, jurist, author, and pioneer of the scientific method. His writings on psychological topics included the nature of knowledge and memory. 1650 – René Descartes died, leaving Treatise of the World, containing his dualistic theory of reality, mind vs. matter. 1672 – Thomas Willis published the anatomical treatise De Anima Brutorum, describing psychology in terms of brain function. 1677 – Baruch Spinoza died, leaving Ethics, Demonstrated in Geometrical Order, Pt. 2 focusing on the human mind and body, disputing Descartes and arguing that they are one, and Pt. 3 attempting to show that moral concepts such as good and evil, virtue, and perfection have a basis in human psychology. 1689 – John Locke published An Essay Concerning Human Understanding, which claims that the human mind is a Tabula Rasa at birth.
18th century 1701 – Gottfried Wilhelm Leibniz published the Law of Continuity, which he applied to psychology, becoming the first to postulate an unconscious mind; he also introduced the concept of threshold. 1710 – George Berkeley published Treatise Concerning the Principles of Human Knowledge, which claims that the outside world is composed solely of ideas. 1732 – Christian Wolff published Psychologia Empirica, followed in 1734 by Psychologia Rationalis, popularizing the term "psychology". 1739 – David Hume published A Treatise of Human Nature, claiming that all contents of mind are solely built from sense experiences. 1781 – Immanuel Kant published Critique of Pure Reason, rejecting Hume's extreme empiricism and proposing that there is more to knowledge than bare sense experience, distinguishing between "a posteriori" and "a priori" knowledge, the former being derived from perception, hence occurring after perception, and the latter being a property of thought, independent of experience and existing before experience. 1783 – Ferdinand Ueberwasser designated himself Professor of Empirical Psychology and Logic at the Old University of Münster; four years later, he published the comprehensive textbook Instructions for the regular study of empirical psychology for candidates of philosophy at the University of Münster which complemented his lectures on scientific psychology. 1798 – Immanuel Kant proposed the first dimensional model of consistent individual differences by mapping the four Hippocrates' temperament types into dimensions of emotionality and energetic arousal. These two dimensions later became an essential part of all temperament and personality models.
19th century
1800s c. 1800 – Franz Joseph Gall developed cranioscopy, the measurement of the skull to determine psychological characteristics, which was later renamed phrenology; it is now discredited. 1807 – Georg Wilhelm Friedrich Hegel published Phenomenology of Spirit (Mind), which describes his thesis-antithesis-synthesis dialectical method, according to which knowledge pushes forwards to greater certainty, and ultimately towards knowledge of the noumenal world. 1808 – Johann Christian Reil coined the term "psychiatry".
1810s 1812 – Benjamin Rush became one of the earliest advocates of humane treatment for the mentally ill with the publication of Medical Inquiries and Observations Upon Diseases of the Mind, the first American textbook on psychiatry.
1820s 1829 – John Stuart Mill's father James Mill published Analysis of the Phenomena of the Human Mind (2 vols.).
1840s 1840 – Frederick Augustus Rauch (1806–1841) published Psychology, or a View of the Human Soul, including Anthropology 1843 – Forbes Benignus Winslow (1810–1874) published The Plea of Insanity in Criminal Cases, helping establish the plea of insanity in criminal cases in Britain. 1844 – Søren Kierkegaard The Concept of Anxiety, the first exposition on anxiety. 1848 – Vermont railroad worker Phineas Gage had a 3-foot rod driven through his brain and jaw in an explosives accident, permanently changing his personality, revolutionizing scientific opinion about brain functions being localizable. 1849 – Søren Kierkegaard published The Sickness Unto Death.
1850s 1852 – Hermann Lotze published Medical Psychology or Physiology of the Soul. 1856 – Hermann Lotze began publishing his 3-volume magnum opus Mikrokosmos (1856–64), arguing that natural laws of inanimate objects apply to human minds and bodies but have the function of enabling us to aim for the values set by the deity, thus making room for aesthetics. 1859 – Pierre Briquet published Traite Clinique et Therapeutique de L'Hysterie.
1860s 1860s – Franciscus Donders first used human reaction time to infer differences in cognitive processing. 1860 – Gustav Theodor Fechner published Elements of Psychophysics, founding the subject of psychophysics. 1861 – Paul Broca discovered an area in the left cerebral hemisphere that is important for speech production, now known as Broca's area, founding neuropsychology. 1869 – Francis Galton published Hereditary Genius, arguing for eugenics. He went on to found psychometrics, differential psychology, and the lexical hypothesis of personality.
1870s 1872 – Douglas Spalding published his discovery of psychological imprinting. 1874 – Wilhelm Wundt published Grundzüge der physiologischen Psychologie (Principles of Physiological Psychology), the first textbook of experimental psychology. 1878 – G. Stanley Hall was awarded the first PhD on a psychological topic from Harvard (in philosophy). 1879 – Wilhelm Wundt opened the first experimental psychology laboratory at the University of Leipzig in Germany.
1880s 1882 – The Society for Psychical Research was founded in England. 1883 – G. Stanley Hall opened the first American experimental psychology research laboratory at Johns Hopkins University. 1883 – Emil Kraepelin published Compendium der Psychiatrie. 1884 – Ivan Pavlov began studying the digestive secretion of animals. 1884 – Tourette's Syndrome was first described. 1885 – Hermann Ebbinghaus published Über das Gedächtnis (On Memory), a groundbreaking work based on self-experiments, first describing the learning curve, forgetting curve, and spacing effect. 1886 – John Dewey published the first American textbook on psychology, titled Psychology. 1886 – Vladimir Bekhterev established the first laboratory of experimental psychology in Russia at Kazan University. 1886 – Sigmund Freud began private practice in Vienna. 1887 – Georg Elias Müller opened the 2nd German experimental psychology research laboratory in Göttingen. 1887 – George Trumbull Ladd (Yale) published Elements of Physiological Psychology, the first American textbook to include a substantial amount of information on the new experimental form of the discipline. 1887 – James McKeen Cattell founded an experimental psychology laboratory at the University of Pennsylvania, the 3rd in the United States. 1887 – G. Stanley Hall founded the American Journal of Psychology with a $500 contribution supplied by Robert Pearsall Smith of the American Society for Psychical Research. 1888 – William Lowe Bryan founded the United States' 4th experimental psychology laboratory at Indiana University. 1888 – Joseph Jastrow founded the United States' 5th experimental psychology laboratory at the University of Wisconsin–Madison. 1888 – G. Stanley Hall left Johns Hopkins for the presidency of the newly founded Clark University in Worcester, Massachusetts 1889 – James Mark Baldwin published the first volume of his Handbook of Psychology, titled "Sense and Intellect". 1889 – Edmund Sanford, a former student of G. Stanley Hall founded the United States' 6th experimental psychology laboratory at Clark University. 1889 – Edward Cowles founded the United States' 7th experimental psychology laboratory at the McLean Asylum in Waverley, Massachusetts 1889 – Harry Kirke Wolfe founded the United States' 8th experimental psychology laboratory at the University of Nebraska.
1890s 1890 – Christian von Ehrenfels published On the Qualities of Form, founding Gestalt psychology. 1890 – William James published The Principles of Psychology. 1890 – James Hayden Tufts founded the United States' 9th experimental psychology laboratory at the University of Michigan. 1890 – G. T. W. Patrick founded the United States' 10th experimental psychology laboratory at the University of Iowa. 1890 – James McKeen Cattell left Pennsylvania for Columbia University where he founded the United States' 11th experimental psychology laboratory. 1890 – James Mark Baldwin founded the first permanent experimental psychology laboratory in the British Empire at the University of Toronto. 1891 – Frank Angell founded the United States' 12th experimental psychology laboratory at the Cornell University. 1891 – Edvard Westermarck described the Westermarck effect, where people raised early in life in close domestic proximity later become desensitized to close sexual attraction, raising theories about the incest taboo. 1892 – G. Stanley Hall et al. founded the American Psychological Association (APA). 1892 – Edward Bradford Titchener took a professorship at Cornell University, replacing Frank Angell who left for Stanford University. 1892 – Edward Wheeler Scripture founded the experimental psychology laboratory at Yale University, the 19th in United States. 1892–1893 – Charles A. Strong opened the experimental psychology laboratory at the University of Chicago, the 20th in the United States, at which James Rowland Angell conducted the first experiments of functionalism in 1896. 1894 – Margaret Floy Washburn was the first woman to be granted a PhD in Psychology after she studied under E. B. Titchener at Cornell University. 1894 – James McKeen Cattell and James Mark Baldwin founded the Psychological Review to compete with Hall's American Journal of Psychology. 1895 – Gustave Le Bon published The Crowd: A Study of the Popular Mind. 1896 – John Dewey published the paper The Reflex Arc Concept in Psychology, founding functionalism. 1896 – The first psychological clinic was opened at the University of Pennsylvania by Lightner Witmer; although often celebrated as marking the birth of clinical psychology, it was focused primarily on educational matters. 1896 – Edward B. Titchener, student of Wilhelm Wundt and originator of the terms "structuralism" and "functionalism" published An Outline of Psychology. 1897 – Havelock Ellis published Sexual Inversion. 1898 – Boris Sidis published The Psychology of Suggestion: A Research into the Subconscious Nature of Man and Society. 1899 – On 4 November Sigmund Freud published The Interpretation of Dreams (Die Traumdeutung), marking the beginning of psychoanalysis, which attempts to deal with the Oedipal complex.
20th century
1900s 1900 – Sigmund Freud published The Psychopathology of Everyday Life. 1903 – John B. Watson graduated from the University of Chicago; his dissertation on rat behavior has been described as a "classic of developmental psychobiology" by historian of psychology Donald Dewsbury. 1903 – Helen Thompson Woolley published her doctoral dissertation, The Mental Traits of Sex, for which she had conducted the first experimental test of sex differences. 1904 – Ivan Pavlov won the Nobel Prize for his studies of conditioning. This was the first Prize given for research adopted by psychologists. 1904 – Charles Spearman published the article General Intelligence in the American Journal of Psychology, introducing the g factor theory of intelligence. 1905- Mary Calkins was the first woman elected president of the American Psychological Association. 1905 – Alfred Binet and Theodore Simon created the Binet-Simon scale to identify students needing extra help, marking the beginning of standardized psychological testing. 1905 – Edward Thorndike published the law of effect. 1905 – Sigmund Freud published Three Essays on the Theory of Sexuality. 1906 – The Journal of Abnormal Psychology was founded by Morton Prince, for which Boris Sidis was an associate editor and significant contributor. 1908 – Sigmund Freud published the paper On the Sexual Theories of Children, introducing the concept of penis envy; he also published the paper 'Civilized' Sexual Morality and Modern Nervous Illness. 1908 – Wilfred Trotter published the first paper explaining the herd instinct. 1909 – Sigmund Freud lectured at Clark University, winning over the U.S. establishment.
1910s 1910 – Sigmund Freud founded the International Psychoanalytical Association (IPA), with Carl Jung as the first president, and Otto Rank as the first secretary. 1910 – Grace Helen Kent and J. Rosanoff published the Kent-Rosanoff Free Association Test 1910 – Boris Sidis opened the private Sidis Psychotherapeutic Institute at Maplewood Farms in Portsmouth, New Hampshire for the treatment of nervous patients using the latest scientific methods. 1911 – Alfred Adler left Freud's Psychoanalytic Group to form his own school of thought, accusing Freud of overemphasizing sexuality and basing his theory on his own childhood. 1911 – The American Psychoanalytic Association (APsaA) was founded. 1911 – William McDougall, founder of Hormic Psychology published Body and Mind: A History and Defence of Animism, claiming that there is an animating principle in Nature and that the mind guides evolution. 1912 – Max Wertheimer published Experimental Studies of the Perception of Movement, helping found Gestalt Psychology 1913 – Carl Jung developed his own theories, which became known as Analytical Psychology. 1913 – Jacob L. Moreno pioneered group psychotherapy methods in Vienna, which emphasized spontaneity and interaction; they later became known as psychodrama and sociometry. 1913 – John B. Watson published Psychology as the Behaviorist Views It, sometimes known as "The Behaviorist Manifesto". 1913 – Hugo Münsterberg published Psychology and Industrial Efficiency, considered today as the first book on Industrial and Organizational Psychology. 1914 – Boris Sidis published The Foundations of Normal and Abnormal Psychology, where he provided the scientific foundation for the field of psychology, and detailed his theory of the moment consciousness. 1917 – Sigmund Freud published Introduction to Psychoanalysis.
1920s 1920 – John B. Watson and his assistant Rosalie Rayner conducted the Little Albert experiment, using classical conditioning to make a young boy afraid of white rats. 1921 – Sigmund Freud published Group Psychology and the Analysis of the Ego. 1921 – Jacob L. Moreno conducted the first large scale public psychodrama session at the Komedienhaus in Vienna; he moved to New York in 1925. 1921 – Melanie Klein began to develop her technique of analyzing children. 1922 – Karen Horney began publishing a series of 14 papers (last in 1937) questioning Freud's theories on women, founding feminist psychology. 1922 – Boris Sidis published Nervous Ills: Their Cause and a Cure, a popularization of his work concerning the subconscious and the treatment of psychopathic disease. 1923 – Sigmund Freud published The Ego and the Id. 1924 – Jacob Robert Kantor founded interbehavioral psychology based on John Dewey's psychology and Albert Einstein's relativity theory. 1924 – Otto Rank published The Trauma of Birth, coining the term "pre-Oedipal". Freud had originally praised him for such, but changed his stance and as such caused their falling out. 1926 – Otto Rank gave the lecture "The Genesis of the Object Relation", founding object relations theory. 1927 – Ivan Pavlov published Conditioned Reflexes, containing his theory of classical conditioning. 1928 – Jean Piaget published Judgment and Reasoning in the Child. 1928 – Shoma Morita published Morita Therapy: The True Nature of Shinkeishitsu (Anxiety-based Disorders), which contains his peripheral theory of consciousness, while noting Freud's theory of the unconscious. (Translation by A. Kondo, Edited by P. LeVine in 1998, SUNY Press) 1929 – Edwin Boring published A History of Experimental Psychology, pioneering the history of psychology. 1929 – Lev Vygotsky founded cultural-historical psychology.
1930s 1930 – Edwin Boring discussed the Boring figure. 1931 – Gordon Allport et al. published the Allport-Vernon-Lindzey Study of Values, which defines six major value types. 1932 – Journal of Personality founded as first personality psychology research periodical originally titled Character and Personality. 1933 – Pyotr Gannushkin published Manifestations of Psychopathies. 1933 – Clark L. Hull published Hypnosis and Suggestibility, proving that hypnosis is not sleep and founding the modern study of hypnosis. 1933 – Wilhelm Reich published Character Analysis and The Mass Psychology of Fascism. 1934 – Lev Vygotsky published Thought and Language (Thinking and Speech). 1934 – Ruth Winifred Howard became the first African American woman to earn a PhD in psychology. 1935 – John Ridley Stroop developed a color-word task to demonstrate the interference of attention, the Stroop effect 1935 – Helen Flanders Dunbar published Emotions and Bodily Changes: A Survey of Literature on Psychosomatic Interrelationships; in 1942 she founded the American Psychosomatic Society (American Society for Research in Psychosomatic Problems), and was the first editor of the society's journal Psychosomatic Medicine: Experimental and Clinical Studies, founded in 1939. 1935 – Henry Murray and Christiana Morgan of Harvard University published the Thematic Apperception Test (TAT). 1935 – Theodore Newcomb began the Bennington College Study, which ended in 1939, documenting liberalization of women students' political beliefs, along with the effects of proximity on acquaintance and attraction. 1936 – Kurt Lewin published Principles of Topological Psychology, containing Lewin's Equation B = f (P, E), meaning that behavior is a function of a person in their environment. 1936 – Wilhelm Reich published The Sexual Revolution. 1936 – Kenneth Spence published an analysis of discrimination learning in terms of gradients of excitation and inhibition, showing that mathematical deductions from a quantitative theory could generate interesting and empirically testable predictions. 1936 – The Psychometric Society was founded by Louis Leon Thurstone, who proposed dividing general intelligence into seven primary mental abilities (PMAs). 1938 – B.F. Skinner published his first major work The Behavior of Organisms: An Experimental Analysis, introducing behavior analysis. 1939 – Alan Hodgkin and Andrew Huxley published a classic report in the journal Nature of the first recording of an action potential. 1939 – Neal E. Miller et al. published the frustration-aggression theory, which claims that aggression is the result of frustration of efforts to attain a goal. 1939 – David Wechsler developed the Wechsler-Bellevue Intelligence Scale. 1939 – On 1 September World War II began with the German invasion of Poland; on 20 September Adolf Hitler signed the Euthanasia Decree, written by psychologist Max de Crinis, resulting in the Aktion T4 euthanasia program; on 23 September Sigmund Freud committed physician-assisted suicide in London on the Jewish Day of Atonement; on 31 October his archrival Otto Rank died of a kidney infection in New York City after uttering the word "comical"; Wilhelm Reich fled to New York, coining the word orgone and building "orgone accumulators", which got him in trouble with the psychiatric establishment and the federal government.
1940s 1940 – Edwin Boring discussed the moon illusion. 1941 – Erich Fromm published Escape from Freedom, founding political psychology. 1941 – B.F. Skinner and William Kaye Estes introduced the conditioned emotional response (CER)/conditioned fear response (CFR) paradigm via electric shocks given to rats. 1942 – Ludwig Binswanger founded existential therapy. 1942 – Carl Rogers published Counseling and Psychotherapy, suggesting that respect and a nonjudgmental approach to therapy is the foundation for effective treatment of mental health issues. 1943 – J. P. Guilford developed the Stanine (Standard Nine) test for the U.S. Air Force to evaluate pilots. 1943 – Clark L. Hull published Principles of Behavior, establishing animal-based learning and conditioning as the dominant learning theory. 1943 – Leo Kanner published Autistic Disturbances of Affective Contact, the first systematic description of autistic children. 1943 – Abraham Maslow published the paper A Theory of Human Motivation, describing Maslow's hierarchy of needs. 1944 – Zach Andrew and Cameron Peter published Myer's Psychology Second Edition where they revolutionized the approach of learned Psychology 1945 – The Journal of Clinical Psychology was founded. 1946 – Kurt Lewin founded action research. 1946 – Stanley Smith Stevens published his levels of measurement theory. 1947 – Jerome Bruner published Value and Need as Organizing Factors in Perception, founding New Look Psychology, which challenges psychologists to study not just an organism's response to a stimulus but also its internal interpretation. 1947 – Kurt Lewin coined the term "group dynamics". 1947 Nikolai Bernstein summarized his research on the measurement of actions using his original devices that became a beginning of a new discipline of kinesiology 1948 – Alfred Kinsey of Indiana University published Sexual Behavior in the Human Male. 1949 – The Boulder Conference outlined the scientist-practitioner model of clinical psychology. 1949 – Donald Hebb published The Organization of Behavior: A Neuropsychological Theory, in which he provided a detailed, testable theory of how the brain could support cognitive processes, revolutionizing neuropsychology and making McGill University a center of research. 1949 – David Wechsler published the Wechsler Intelligence Scale for Children (WISC).
1950s 1950 – Karen Horney summarized her ideas in her magnum opus Neurosis and Human Growth: The Struggle Toward Self-Realization. 1950 – Erik Erikson published Childhood and Society, in which he introduced his theory on the stages of psycho-social development and the concept of an identity crisis. 1950 – Rollo May published The Meaning of Anxiety. 1951 – Solomon Asch published the Asch conformity experiments, demonstrating the power of conformity in groups. 1951 – Morton Deutsch published Interracial Housing: A Psychological Evaluation of a Social Experiment, producing scientific evidence of the bad effects of segregated housing, helping to end it in the U.S. 1951 – Carl Rogers published his magnum opus Client-Centered Therapy. 1951 – Lee Cronbach published his measure of reliability, now known as Cronbach's alpha. 1952 – The Diagnostic and Statistical Manual of Mental Disorders (DSM) was published by the American Psychiatric Association (APA), marking the beginning of modern mental illness classification; it was revised in 1968, 1980–7, 1994, 2000 and 2013. 1952 – Hans Eysenck started a debate on psychotherapy with his critical review, claiming that psychotherapy had no documented effect, and psychoanalysis had negative effects. 1953 – Alfred Kinsey published Sexual Behavior in the Human Female. 1953 – Nathaniel Kleitman of the U. of Chicago discovered rapid eye movement sleep (REM), founding modern sleep research. 1953 – David McClelland proposed need theory. 1953 – B.F. Skinner outlined behavioral therapy, lending support for behavioral psychology via research in the literature. 1953 – The Code of Ethics for Psychologists was developed by the American Psychological Association (APA). 1953 – Harry Stack Sullivan published The Interpersonal Theory of Psychiatry, which holds that an individual's personality is formed by relationships. 1954 – Abraham Maslow helped to found humanistic psychology, later developing Maslow's hierarchy of needs. 1954 – Paul E. Meehl published a paper claiming that mechanical (formal algorithmic) methods of data combination outperform clinical (subjective informal) methods when used to arrive at a prediction of behavior. 1954 – James Olds and Peter Milner of McGill University discovered the brain reward system, involving the brain's pleasure center. 1954 – Julian Rotter published Social Learning and Clinical Psychology, founding social learning theory. 1954 – Herman Witkin published Personality Through Perception, which claims that personality can be revealed through differences in how people perceive their environment; he went on to develop the Rod and Frame Test (RFT). 1954 – Bronisław Malinowski publishes Magic, Science and Religion on magical thinking and the psychology of religion. Earlier, he studied sets of rituals he referred to as magic, and distinguished these from purely religious rituals, with the latter's purpose being the coping with one's fundamental human crisis of apparent finiteness/mortality. 1955 – Lee Cronbach published Construct Validity in Psychological Tests, popularizing the concept of construct validity. 1955 – J. P. Guilford developed the Structure of Intellect (SOI) theory, which divides human intelligence into 150 abilities along three dimensions, operations, content, and products; it is discredited by the 1990s. 1955 – George Kelly founded personal construct psychology. 1956 – George Armitage Miller published the paper The Magical Number Seven, Plus or Minus Two, in which he showed that there is a limit on the amount of information that can be memorized at one time. 1956 – Rollo May published Existence, promoting existential psychology. 1957 – Leon Festinger published his theory of cognitive dissonance. 1957 – Stanley Smith Stevens published Stevens' power law. 1957 – Eric Berne developed Transactional analysis (TA), in which psychiatry patients can be treated for emotional distresses by analyzing and altering their social transactions. 1958 – John Cohen published Humanistic Psychology, the first book on the subject. 1958 – Harry Harlow gave the speech The Nature of Love, summarizing his isolation studies on infant monkeys and rejecting behavioristic and psychoanalytic theories of attachment. 1958 – Joseph Wolpe published his theory of reciprocal inhibition, leading to his theory of systematic desensitization for anxieties and phobias. 1959 – Viktor Frankl published the first English edition of Man's Search for Meaning [with a preface by Gordon Allport], which provided an existential account of his Holocaust experience and an overview of his system of existential analysis called Logotherapy. 1959 – Noam Chomsky published his review of B.F. Skinner's Verbal Behavior, an event seen as by many as the start of the cognitive revolution. 1959 – George Mandler and William Kessen published The Language of Psychology. 1959 – Lawrence Kohlberg wrote his doctoral dissertation, outlining Kohlberg's stages of moral development.
1960s 1960 – John L. Fuller and W. Robert Thompson published the seminal text Behavior Genetics. 1960 – Thomas Szasz inaugurated the anti-psychiatry movement with the publication of his book, The Myth of Mental Illness. 1961 – Albert Bandura published the Bobo doll experiment, a study of behavioral patterns of aggression. 1961 – Neal E. Miller proposed the use of biofeedback to control involuntary functions. 1962 – Wilfred Bion presented his unconventional theory of thinking. 1962 – Albert Ellis published Reason and Emotion in Psychotherapy, describing the theoretical foundations of his therapeutic system known as Rational Emotive Behavior Therapy. 1962 – George Armitage Miller published Psychology, the Science of Mental Life, rejecting the idea that psychology should study only behavior. 1962 – Abraham Maslow published Toward a Psychology of Being, presenting his ideas of self-actualization and the hierarchy of human needs. 1962 – Stanley Schachter and Jerome Singer proposed the two-factor theory of emotion, which considers emotion to be a function of both cognitive factors and physiological arousal; "People search the immediate environment for emotionally relevant cues to label and interpret unexplained physiological arousal." 1962 – Silvan Tomkins published volume one (of two) of Affect Imagery Consciousness, presenting his affect theory 1963 – Stanley Milgram published his study of obedience to authority, now known as the Milgram experiment. 1964 – Jean M. Mandler and George Mandler published Thinking: From Association to Gestalt. 1964 – Virginia Satir published Conjoint Family Therapy, the first of several books on family therapy, causing her to become known as the "Mother of Family Therapy" 1965 – Anna Freud published Normality and Pathology in Childhood: Assessments of Development, presenting the concept of developmental lines. 1965 – William Glasser published Reality Therapy, describing his psycho-therapeutic model and introducing his concept of control theory [later renamed to Choice Theory]. 1965 – Donald Winnicott published The Maturational Process and the Facilitating Environment, which became a main text in clinical psychodynamic developmental psychology. 1966 – Nancy Bayley became the first woman to receive the APA Distinguished Scientific Contribution Award for her contribution in developmental psychology. 1966 – Konrad Lorenz published On Aggression, which discusses his hydraulic model of instinctive pressures. 1966 – Masters and Johnson published Human Sexual Response. 1966 – Julian Rotter published a paper proposing the Internal-External Locus of Control Scale (I-E Scale). 1967 – Aaron Beck published a psychological model of clinical depression, suggesting that thoughts play a significant role in the development and maintenance of depression. 1967 – Edward E. Jones and Victor Harris published a paper defining fundam