Date | Milestone
387 | Plato (Greece) argues that the brain is the center of mental process.
335 | Aristotle (Greece) argues that the heart is the center of mental process.
1637 | René Descartes (France) publishes A Discourse on Method. Descartes asserts that ideas are innate to humans from birth.
1690 | John Locke (England) publishes An Essay Concerning Human Understanding. Locke asserts that ideas come from experience and the human ability to reason.
1774 | Franz Mesmer (Austria) presents a treatment for mental illnesses, originally called mesmerism and now known as hypnosis.
1794 | Philippe Pinel (France) publishes Memoir on Madness. It argues for humane treatment of mentally ill patients. Pinel made significant contributions to the classification of mental disorders.
1808 | Franz Joseph Gall (Germany) proposes the idea of phrenology, the belief that the shape of a person’s skull reveals personality traits.
1848 | Phineas Gage (United States) suffers massive brain damage when his brain is pierced by a large iron rod. This leaves his intellect intact, but his personality is changed. From this, researchers study how areas in the brain play a role in personality.
1856 | Hermann von Helmholtz (Germany) publishes Handbook of Physiological Optics. His many works make important contributions, including reports on the physiology of vision and hearing, and measurement of nerve impulse speed.
1859 | Charles Darwin (England) publishes On the Origin of Species. Darwin asserts that species evolve, and that living beings all share a common ancestor.
1861 | Paul Broca (France) presents his findings regarding the area in the left frontal lobe of the brain that is critical for the production of spoken language. This is now called Broca’s area.
1869 | Francis Galton (England) publishes Hereditary Genius. He asserts that intelligence is inherited. Galton is credited with the expression “nature and nurture” to correspond with “heredity and environment.”
1874 | Carl Wernicke (Germany) presents his findings that damage to a specific area in the left temporal lobe damages the ability to comprehend or produce language. This is now called Wernicke’s area.
1879 | Wilhelm Wundt (Germany) founds the first formal laboratory for psychological study at the University of Leipzig. Wundt, the first person to refer to himself as a psychologist, helped to establish psychology as an independent field of study.
1883 | The first formal U.S. psychology laboratory is established at Johns Hopkins University.
1885 | Hermann Ebbinghaus (Germany) publishes On Memory. Ebbinghaus made numerous contributions to the areas of learning and memory.
1887 | G. Stanley Hall (United States) founds the American Journal of Psychology. Hall was the first North American to receive a PhD in psychology.
1890 | William James (United States) publishes Principles of Psychology. His research contributes to the study of functionalism. He is also the first person to teach a psychology course in the United States.
1892 | The American Psychological Association (APA) is organized by G. Stanley Hall. The APA’s stated mission is to promote the advancement, communication, and application of psychological science and knowledge to benefit society and improve lives.
1894 | Margaret Floy Washburn (United States) is the first woman to receive a PhD in psychology. She made contributions in the fields of animal behavior and motor theory development.
1896 | John Dewey (United States) publishes The Reflex Arc Concept in Psychology. He focused on the areas of education and helped develop the psychological philosophy of functionalism.
1898 | Edward Thorndike (United States) publishes Animal Intelligence. His work proposes that animals and humans learn similarly and leads to the development of operant conditioning.
1900 | Sigmund Freud (Austria, England) publishes The Interpretation of Dreams. Freud is considered the founder of psychoanalysis.
1901 | Mary Whiton Calkins (United States) publishes An Introduction to Psychology. In 1905, she is the first female elected as president of the American Psychological Association.
1903 | Alfred Binet (France) publishes Experimental Studies of Intelligence. Binet made contributions to the study of intelligence, including the creation, along with colleague Theodore Simon, of the Binet-Simon intelligence scale.
1906 | Ivan Pavlov (Russia) publishes his first studies on classical conditioning.
1912 | Carl Jung (Switzerland) publishes Psychology of the Unconscious. Jung is considered the founder of analytical psychology.
1912 | Tsuruko Haraguchi (Japan) receives a PhD in psychology. She is the first Japanese woman to receive a PhD in any subject.
1913 | John Watson (United States) publishes The Behaviorist Manifesto. This puts forth a new area called behaviorism. In 1920, he and his colleague and wife, Rosalie Raynor, conducted the controversial “Little Albert” experiment.
1920 | Francis Cecil Sumner (United States) receives a PhD in psychology. He is the first African American to earn a PhD in psychology. His work focuses on race psychology and education reform.
1921 | Hermann Rorschach (Switzerland) publishes Psychodiagnostik. This work introduces the Rorschach Inkblot Test.
1923 | Jean Piaget (Switzerland) publishes The Language and Thought of the Child. Piaget contributed in the area of child development, and championed child education.
1926 | Leta Stetter Hollingworth (United States) publishes Gifted Children. Her work in the psychology of women helped to dispel myths that had been used to argue against women’s rights.
1927 | Anna Freud (Austria, England), the sixth and youngest child of Sigmund Freud, publishes Introduction to the Technique of Child Analysis. Freud developed the field of child psychoanalysis.
1929 | Christine Ladd-Franklin (United States) publishes Color and Color Theories. Ladd-Franklin makes contributions in the field of color vision, in addition to other fields.
1929 | Wolfgang Köhler (Germany) publishes Gestalt Psychology. This work criticizes behaviorism.
1932 | Walter B. Cannon (United States) publishes The Wisdom of the Body. This work introduces the term homeostasis and discusses the fight-or-flight response.
1933 | Inez Beverly Prosser (United States) becomes the first African American woman to receive a doctoral degree in psychology from a U.S. institution.
1936 | Anna Freud (Austria, England) publishes her influential book, The Ego and the Mechanisms of Defense.
1936 | Egas Moniz (Portugal) publishes work on the first human frontal lobotomies.
1936 | Herman George Canady (United States) publishes The Effect of “Rapport” on the I.Q.: A New Approach to the Problem of Race Psychology. He was the first psychologist to examine the role of the examiner’s race as a bias factor in IQ testing. His work provided suggestions for establishing a more equal testing environment.
1938 | Ugo Cerletti (Italy) and Lucio Bini (Italy) use electroshock treatment on a human patient.
1939 | David Wechsler (Romania, United States) publishes the Wechsler-Bellevue intelligence test, which will later evolve into the Wechsler Intelligence Scale for Children (WISC) and the Wechsler Adult Intelligence Scale (WAIS).
1940 | George I. Sanchez (United States) publishes Forgotten People: A Study of New Mexicans. Also in 1940, he receives a tenured, full professorship at the University of Texas, where he becomes the first professor of Latin American Studies.
1943 | Starke Hathaway (United States) and J. Charnley McKinley (United States) publishes the Minnesota Multiphasic Personality Inventory (MMPI).
1945 | Karen Horney (Germany, United States) publishes Our Inner Conflicts. Her work criticizes Freud’s theory of female sexual development.
1946 | Mamie Phipps Clark (United States) founds the Northside Center for Child Development. The first program of its kind in Harlem, it offers necessary therapy and assistance to children and families.
1948 | Alfred Kinsey (United States) publishes Sexual Behavior in the Human Male, and then Sexual Behavior in the Human Female in 1953 with colleagues.
1948 | B. F. Skinner (United States) publishes Walden Two. It describes a utopian community based on positive reinforcement and an experimental attitude. The book encourages the application of psychological principles to everyday life.
1949 | Donald O. Hebb (Canada) publishes The Organization of Behavior: A Neuropsychological Theory. It offers a new and influential conceptualization about how the nervous system functions.
1950 | Erik Erikson (Germany, United States) publishes Childhood and Society. He made contributions that advanced the study of human development across the lifespan.
1951 | Carl Rogers (United States) publishes Client-Centered Therapy. His work advanced the humanist movement.
1952 | The American Psychiatric Association publishes the first Diagnostic and Statistical Manual of Mental Disorders (DSM), an influential text that is updated periodically.
1953 | Janet Taylor Spence (United States) publishes her Taylor Manifest Anxiety Scale in the Journal of Abnormal Psychology. Her contributions advanced the fields of anxiety and gender studies.
1954 | Abraham Maslow (United States) publishes Motivation and Personality. It proposes a hierarchy of needs, ranging from physiological needs to self-actualization.
1954 | Gordon Allport (United States) publishes The Nature of Prejudice. He was one of the first psychologists to study personality.
1955 | Kenneth Clark (United States) publishes Prejudice and Your Child. His earlier research and experiments with his colleague and wife, Mamie Phipps Clark, explored issues of race for African American children. The findings of that research were included as evidence in the Supreme Court decision Brown v. Board of Education (1954) by proving that segregation psychologically harms children.
1957 | B. F. Skinner (United States) publishes Schedules of Reinforcement. He contributed in the areas of behavior analysis and the experimental analysis of behavior.
1957 | Leon Festinger (United States) proposes his theory of cognitive dissonance; in 1959, he and his colleague James Carlsmith conducts a landmark experiment to test this theory at Stanford University.
1958 | Lawrence Kohlberg (United States) proposes his theory of moral development.
1960 | Beatrice Ann Wright (United States) publishes Physical Disability: A Psychological Approach. Her contributions include developing appropriate and culturally relevant ways of working with differently abled people.
1961 | Aaron Beck (United States) creates the Beck Depression Inventory, which is still used widely. Beck’s contributions include the development of cognitive therapy and cognitive-behavioral therapy, along with making advances in the study of clinical depression and anxiety disorders.
1967 | Zing-Yang Kuo (China) publishes The Dynamics of Behavior in Development. He contributed in the areas of animal and comparative psychology.
1967 | Raymond Cattell (England, United States) publishes Objective Personality and Motivation Tests. He made contributions in the field of personality, putting forth a taxonomy of 16 different personality traits that could explain differences in peoples’ personalities.
1969 | Eleanor Gibson (United States) publishes Principles of Perceptual Learning and Development. With colleague Richard Walk (United States), Gibson conducts research on infant depth perception, known as “The Visual Cliff.”
1971 | Phillip Zimbardo (United States) conducts the Stanford Prison Experiment in the basement of an academic hall to examine the effects of authority in a prison environment.
1971 | Albert Bandura (Canada, United States) publishes Social Learning Theory. His contributions advance the field of social cognitive psychology, and he is well known for his experiments regarding aggression.
1972 | Elliot Aronson (United States) publishes The Social Animal. His contributions lead to advances in the theory of cognitive dissonance and explore the importance of situational factors on behavior.
1974 | Eleanor Maccoby (United States) and Carol Jacklin (United States) publish The Psychology of Sex Differences. Their contributions lead to advances in the fields of gender studies and developmental psychology.
1974 | Stanley Milgram (United States) publishes Obedience to Authority: An Experimental View. Milgram may be best known for his controversial experiments on obedience, which researched to what extent people would obey orders, even if the orders were dangerous or immoral.
1976 | Robert V. Guthrie (United States) publishes Even the Rat Was White, the first history of African American psychologists in the United States.
1979 | James J. Gibson (United States) publishes The Ecological Approach to Visual Perception. His contributions lead to advances in the field of visual perception.
1979 | Elizabeth Loftus (United States) publishes Eyewitness Testimony. Her contributions lead to advances in the field of memory, misinformation, and eyewitness memory.
1983 | Howard Gardner (United States) publishes Frames of Mind. This work outlines his theory of multiple intelligences.
1984 | Hiroshi Azuma (Japan) publishes “Psychology in a Non-Western Country” in the International Journal of Psychology. He made contributions in the areas of cross-cultural psychology.
1986 | Durganand Sinha (India) publishes Psychology in a Third World Country: The Indian Experience. He studied indigenous psychology; self, family, and social values; and human and socioeconomic development. He was central to the modern development of psychology from an Indian perspective.
1987 | Marius Romme (Amsterdam) founds the Hearing Voices Network with Sandra Escher, a science journalist, and Patsy Hage, a person who hears voices. The network serves as a peer-mentor organization for persons who have auditory hallucinations and their supporters. The network soon spreads across the world.
1988 | Muzafer Sherif (Turkey, United States) publishes The Robbers Cave Experiment with colleagues. One of the founders of modern social psychology, he advanced the fields of social judgment theory and realistic conflict theory.
1988 | The Association for Psychological Science (APS), previously the American Psychological Society, is founded. Its stated mission is to promote, protect, and advance the interests of scientifically oriented psychology in research, application, teaching, and the improvement of human welfare.
1989 | Kimberlé Williams Crenshaw (United States) publishes the paper “Demarginalizing the Intersection of Race and Sex.” She is one of the founders of critical race theory, developing the theory of intersectionality.
1990 | Reiko True (Japan, United States) publishes “Psychotherapeutic Issues with Asian American Women” in the journal Sex Roles. Her work has advanced mental health services for Asian Americans and other minorities.
1991 | Martin Seligman (United States) publishes Learned Optimism. This work introduces the field of positive psychology.
1991 | Qicheng Jing (China) publishes Landmarks of Psychology: Contemporary Great Masters in Psychology. He made contributions in highlighting the international aspect of psychology, advancing the exchange of international psychology, and lifting Chinese psychology onto the world stage.
1997 | Beverly Daniel Tatum (United States) publishes Why Are All the Black Kids Sitting Together in the Cafeteria? This work examines the development of racial identity.
1997 | U.S. president Bill Clinton apologizes for the Tuskegee Syphilis Study, an infamous study done on African Americans that violated participants' rights and led to the publishing of the Belmont Report in 1979, a U.S. code of ethics for human participants in research.
2003 | Kuo-Shu Yang (China, Taiwan) publishes Progress in Asian Social Psychology with colleagues. A pioneer in indigenous Chinese and Taiwanese psychology, he also devoted his life to social reform in Taiwan.
2007 | Alice Eagly (United States) publishes Through the Labyrinth: The Truth about How Women Become Leaders with colleague Linda Carli (United States). Her contributions have advanced the understanding of prejudice, sex differences, leadership styles, feminism, and stereotypes.
2008 | U.S. president George W. Bush signs Mental Health Parity Act, requiring insurance to equally cover both mental and physical health.
2008 | Lisa Diamond publishes Sexual Fluidity: Understanding Women’s Love and Desire. Her research has advanced the understanding of sexual identity, sexual orientation development, and human bonding.
2010 | Derald Wing Sue (United States) publishes Microaggressions in Everyday Life: Race, Gender, and Sexual Orientation. His contributions have advanced the fields of multicultural counseling and research.
2010 | Claude Steele (United States) publishes Whistling Vivaldi and Other Clues to How Stereotypes Affect Us. He has advanced the areas of stereotype threat and its impact on the academic performance of minority students.
2010 | The replication controversy impacts how a variety of disciplines, including psychology, validate existing studies.
2011 | Michael Gazzaniga (United States) publishes Who’s in Charge? Free Will and the Science of the Brain. His studies advance understanding of the functions of each brain hemisphere, and how they work independently and in collaboration.
2011 | Daniel Kahneman (Israel) publishes Thinking, Fast and Slow. His contributions have advanced the fields of judgment and decision making. With colleague Amos Tversky (Israel), Kahneman has established a cognitive basis for common human errors that arise from heuristics and biases.
2013 | DSM-5 is published by the American Psychiatric Association.
2014 | A radio soap opera, “Musekeweya” is created by clinical psychologist Ervin Staub (Hungary, United States) and disseminated to Rwandan listeners to counteract hate speech and intolerance.
2015 | The American Psychological Association bans psychologist participation in national security interrogations.
2015 | Mona Amer (Egypt) and Germine Awad (United States) publish The Handbook of Arab American Psychology. It is the first major publication to comprehensively discuss the Arab American experience from a primarily psychological lens.
2015 | David Trafimow (United States) bans null hypothesis significance testing for the journal Basic and Applied Social Psychology. This begins the debate about how to better determine if a hypothesis is supported or rejected.
2016 | U.S. president Barack Obama signs the 21st Century Cures Act, which provides essential prevention services and treatments for populations in need and support.
2016 | Mahzarin Banaji (India, United States) publishes Blindspot: Hidden Biases of Good People with colleague Anthony Greenwald (United States). Her work has advanced awareness of implicit or unconscious bias.
2017 | Arkansas (United States) opens the first intimate partner violence shelter for men in the United States. The shelter also runs a domestic violence hotline for men.
2018 | Mental Health at Work (United Kingdom) is launched by The Royal Foundation. The nonprofit provides support to employers and employees to help them improve well-being in their workplace and encourage conversations about mental health.
2019 | Jennifer Eberhardt (United States) publishes Biased: Uncovering the Hidden Prejudice That Shapes What We See, Think, and Do. Her research advances the fields of race, bias, and inequality.
2020 | In Mexico, a mental health bill that would have removed a person’s right to consent to treatment was stopped by human rights activists.
2020 | Telemental health availability broadens treatment options during the coronavirus pandemic.
2021 | American Psychological Association apologizes for contributions to systemic racism, and vows to achieve the social equality, health equity, and fairness that all human beings deserve.