387 BC Plato suggested that the brain is the mechanism of mental processes.
335 BC Aristotle suggested that the heart is the mechanism of mental processes.
1774 AD Franz Mesmer detailed his cure for some mental illness, originally called mesmerism and now known as hypnosis.
1793 Philippe Pinel released the first mental patients from confinement in the first massive movement for more humane treatment of the mentally ill.
1808 Franz Gall wrote about phrenology (the idea that a person's skull shape and placement of bumps on the head can reveal personality traits.
1834 Ernst Heinrich Weber published his perception theory of 'Just Noticeable Difference,' now known as Weber's Law.
1848 Phineas Gage suffered brain damage when an iron pole pierces his brain. His personality was changed but his intellect remained intact suggesting that an area of the brain plays a role in personality.
1859 Charles Darwin published the On the Origin of Species, detailing his view of evolution and expanding on the theory of 'Survival of the fittest.'
1861 French physician Paul Broca discovered an area in the left frontal lobe that plays a key role in language development.
1869 Sir Francis Galton, Influenced by Charles Darwin's 'Origin of the Species,' publishes 'Hereditary Genius,' and argues that intellectual abilities are biological in nature.
1874 Carl Wernicke published his work on the frontal lobe, detailing that damage to a specific area damages the ability to understand or produce language
1878 G. Stanley Hall received the first American Ph.D. in psychology. He later founded the American Psychological Association.
1879 Wilhelm Wundt founded the first formal laboratory of Psychology at the University of Leipzig, marking the formal beginning of the study of human emotions, behaviors, and cognitions.
1883 The first laboratory of psychology in America is established at Johns Hopkins University.
1885 Herman Ebbinghaus introduced the nonsense syllable as a means to study memory processes.
1886 Sigmund Freud began performing therapy in Vienna, marking the beginning of personality theory.
1890 The term "Mental Tests" was coined by James Cattell, beginning the specialization in psychology now known as psychological assessment.
1890 Sir Francis Galton developed the technique known as the correlation to better understand the interrelationships in his intelligence studies.
1890 William James published 'Principles of Psychology,' that later became the foundation for functionalism.
1890 New York State passed the State Care Act, ordering indigent mentally ill patients out of poor-houses and into state hospitals for treatment and developing the first institution in the U.S. for psychiatric research.
1892 Foundation of the American Psychological Association (APA) headed by G. Stanley Hall, with an initial membership of 42.
1895 Alfred Binet founded the first laboratory of psychodiagnosis.
1896 Writings by John Dewey began the school of thought known as functionalism.
1896 The first psychological clinic was developed at the University of Pennsylvania marking the birth of clinical psychology.
1898 Edward Thorndike developed the 'Law of Effect,' arguing that "a stimulus-response chain is strengthened if the outcome of that chain is positive."
1900 Sigmund Freud published 'Interpretation of Dreams' marking the beginning of Psychoanalytic Thought.
1901 The British Psychological Society was founded.
1905 Alfred Binet's Intelligence Test was published in France.
1906 The Journal of Abnormal Psychology was founded by Morton Prince.
1906 Ivan Pavlov published the first studies on Classical Conditioning.
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 Edward Thorndike published first article on animal intelligence leading to the theory of Operant Conditioning.
1912 William Stern developed the original formula for the Intelligence Quotient (IQ) after studying the scores on Binet's intelligence test. The formula is
1912 Max Wertheimer published research on the perception of movement, marking the beginnings of Gestalt Psychology.
1913 John E. Watson published 'Psychology as a Behaviorist Views It' marking the beginnings of Behavioral Psychology.
1913 Carl G. Jung departed from Freudian views and developed his own theories citing Freud's inability to acknowledge religion and spirituality. His new school of thought became known as Analytical Psychology.
1916 Stanford-Binet intelligence test was published in the United States.
1917 Robert Yerkes (President of APA at the time) developed the Army Alpha and Beta Tests to measure intelligence in a group format. The tests were adopted for use with all new recruits in the U.S. military a year later.
1920 John B. Watson and Rosalie Rayner published the Little Albert experiments, demonstrating that fear could be classically conditioned.
1921 Psychological Corporation launched the first psychological test development company, not only commercializing psychological testing, but allowing testing to take place at offices and clinics rather than only at universities and research facilities.
1925 Wolfgang Kohler published 'The Mentality of Apes' which became a major component of Gestalt Psychology.
1927 Anna Freud, daughter of Sigmund Freud, published her first book expanding her father's ideas in the treatment of children.
1929 Wolfgang Kohler criticizes behaviorism in his publication on Gestalt Psychology.
1932 Jean Piaget published 'The Moral Judgment of Children' beginning his popularity as the leading theorist in cognitive development.
1932 Walter B. Cannon coined the term homeostasis and began research on the fight or flight phenomenon.
1935 Thematic Apperception Test (TAT) was published by Henry Murray.
1936 Egas Moniz published his work on frontal lobotomies as a treatment for mental illness.
1938 Electroshock therapy was first used on a human patient.
1939 Wechsler-Bellevue Intelligence Test was published which eventually became the most widely used intellectual assessment.
1939 The Canadian Psychological Associated was founded.
1942 Carl Rogers published 'Counseling and Psychotherapy' suggesting that respect and a non-judgmental approach to therapy is the foundation for effective treatment of mental health issues.
1942 Jean Piaget published 'Psychology of Intelligence' discussing his theories of cognitive development.
1942 Minnesota Multiphasic Personality Inventory (MMPI) was developed and fast became the most widely researched and widely accepted psychological assessment device.
1945 The state of Connecticut passed licensure legislation for psychologists, becoming the first state to recognize psychology as a protected practice oriented profession.
1945 The Journal of Clinical Psychology was founded.
1945 Karen Horney published her feministic views of psychoanalytic theory, marking the beginning of feminism.
1949 Boulder Conference outlines scientist-practitioner model of clinical psychology, looking at the M.D. versus Ph.D. used by medical providers and researchers, respectively.
1950 Erik Erikson published 'Childhood and Society,' where he expands Freud's Theory to include social aspects of personality development across the lifespan.
1952 A study on psychotherapy efficacy was published by Hans Eysenck suggesting that therapy is no more effective that no treatment at all. This prompted an onslaught of outcome studies which have since shown psychotherapy to be an effective treatment for mental illness.
1952 The Diagnostic and Statistical Manual of Mental Disorders (DSM) was published by The American Psychiatric Association marking the beginning of modern mental illness classification.
1952 Chlorpromazine (Thorazine) first used in the treatment of schizophrenia.
1953 B.F. Skinner outlined behavioral therapy, lending support for behavioral psychology via research in the literature.
1953 Code of Ethics for Psychologists was developed by the American Psychological Association.
1954 Abraham Maslow helped to found Humanistic Psychology and later developed his famous Hierarchy of Needs.
1957 Leon Festinger proposed his theory of 'Cognitive Dissonance' and later became an influence figure in Social Psychology.
1961 John Berry introduced the importance of cross-cultural research bringing diversity into the forefront of psychological research and application.
1961 Carl Rogers published 'On Becoming a Person,' marking a powerful change in how treatment for mental health issues is conducted.
1963 Alfred Bandura introduced the idea of Observational Learning on the development of personality.
1963 Lawrence Kolberg introduced his ideas for the sequencing of morality development.
1967 Aaron Beck published a psychological model of depression suggesting that thoughts play a significant role in the development and maintenance of depression.
1968 DSM II was published by the American Psychiatric Association.
1968 First Doctor of Psychology (Psy.D.) professional degree program in Clinical Psychology was established in the Department of Psychology at The University of Illinois - Urbana/Champaign.
1969 Joseph Wolpe published 'The Practice of Behavior Therapy.'
1971 First Doctorate in Psychology (Psy.D.) awarded (from The University of Illinois - Urbana/Champaign).
1973 APA endorsed the Psy.D. degree for professional practice in psychology.
1980 DSM III published by the American Psychiatric Association.
1983 Howard Gardner (professor at Harvard University) introduced his theory of multiple intelligence, arguing that intelligence is something to be used to improve lives not to measure and quantify human beings.
1988 American Psychological Society established.
1990 The emergence of managed care prompts the APA to become more political, leading to the idea of Prescribing Psychologists and equity in mental health coverage.
1994 DSM IV published by the American Psychiatric Association.
1995 First Psychologists prescribe medication through the U.S. military's psychopharmacology program.
1997 Deep Blue, the supercomputer at the time, beats the World's best chess player, Kasparov, marking a milestone in the development of artificial intelligence.
1998 Psychology advances to the technological age with the emergence of e-therapy.
1999 Psychologists in Guam gain prescription privileges for psychotropic medication.
2002 New Mexico becomes the first state to pass legislation allowing licensed psychologists to prescribe psychotropic medication.
2002 The push for mental health parity gets the attention of the White House as President George W. Bush promotes legislation that would guarantee comprehensive mental health coverage.