Basics A Historical Timeline of Modern Psychology A brief look at the people and events that shaped modern psychology By Kendra Cherry, MSEd Kendra Cherry, MSEd Facebook Twitter Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book." Learn about our editorial process Updated on May 17, 2022 Fact checked Verywell Mind content is rigorously reviewed by a team of qualified and experienced fact checkers. Fact checkers review articles for factual accuracy, relevance, and timeliness. We rely on the most current and reputable sources, which are cited in the text and listed at the bottom of each article. Content is fact checked after it has been edited and before publication. Learn more. by Emily Swaim Fact checked by Emily Swaim LinkedIn Emily is a board-certified science editor who has worked with top digital publishing brands like Voices for Biodiversity, Study.com, GoodTherapy, Vox, and Verywell. Learn about our editorial process Print Bettmann Archive / Getty Images The history of modern psychology spans centuries, with the earliest known mention of clinical depression appearing in 1500 BCE on an ancient Egyptian manuscript known as the Ebers Papyrus. However, it wasn't until the 11th century that Persian physician Avicenna made a connection between emotions and physical responses in a practice dubbed "physiological psychology." Understanding the history of modern psychology provides insight into how this field has developed and evolved over time. It also gives a better understanding of the thought processes of some of the most influential figures in the field, ultimately emerging into psychology as we know it today. The Birth of Modern Psychology Some say that modern psychology was born in the 18th century, which is largely due to William Battie's "Treatise on Madness," published in 1758. Others consider the mid-19th century experiments conducted in Hermann von Helmholtz's lab to be the origin of modern psychology. Still others suggest that modern psychology began in 1879 when Wilhelm Wundt—also known as the father of modern psychology—established the first experimental psychology lab. From that moment forward, the study of psychology would evolve, as it still does today. Important Events in the History of Modern Psychology A number of important, landmark events highlight psychology's transformation throughout the years. 19th Century In the 19th century, psychology was established as an empirical, accepted science. While measures would change, the model of research and evaluation would begin to take shape within this 100-year time span. 1878: G. Stanley Hall becomes the first American to earn a Ph.D. in psychology. 1879: Wilhelm Wundt establishes the first experimental psychology lab in Leipzig, Germany dedicated to the study of the mind. 1883: G. Stanley Hall opens the first experimental psychology lab in the U.S. at Johns Hopkins University. 1885: Herman Ebbinghaus publishes his seminal "Über das Gedächtnis" ("On Memory"), in which he describes learning and memory experiments he conducted on himself. 1886: Sigmund Freud begins offering therapy to patients in Vienna, Austria. 1888: James McKeen Cattell becomes the first professor of psychology at the University of Pennsylvania. He would later publish "Mental Tests and Measurements," marking the advent of psychological assessment. 1890: William James publishes "Principles of Psychology." Sir Francis Galton establishes correlation techniques to better understand the relationship between variables in intelligence studies. 1892: G. Stanley Hall forms the American Psychological Association (APA), enlisting 26 members in the first meeting. 1896: Lightner Witmer establishes the first psychology clinic in America. 1898: Edward Thorndike develops the Law of Effect. 1900 to 1950 The first half of the 20th century was dominated by two major figures: Sigmund Freud and Carl Jung. During this segment of modern psychology's history, these two theorists established the foundation of analysis, including Freud's examination of psychopathology and Jung's analytic psychology. 1900: Sigmund Freud publishes his landmark book, "Interpretation of Dreams." 1901: The British Psychological Society is established. 1905: Mary Whiton Calkins is elected the first woman president of the American Psychological Association. Alfred Binet introduces the intelligence test. 1906: Ivan Pavlov publishes his findings on classical conditioning. Carl Jung publishes "The Psychology of Dementia Praecox." 1911: Edward Thorndike publishes "Animal Intelligence," which leads to the development of the theory of operant conditioning. 1912: Max Wertheimer publishes "Experimental Studies of the Perception of Movement," which leads to the development of Gestalt psychology. 1913: Carl Jung begins to depart from Freudian views and develop his own theories, which he refers to as analytical psychology. John B. Watson publishes "Psychology As the Behaviorist Views," in which he establishes the concept of behaviorism. 1915: Freud publishes work on repression. 1920: Watson and Rosalie Rayner publish research on the classical conditioning of fear, highlighting the subject of their experiment, Little Albert. 1932: Jean Piaget becomes the foremost cognitive theorist with the publication of his work "The Moral Judgment of the Child." 1942: Carl Rogers develops the practice of client-centered therapy, which encourages respect and positive regard for patients. 1950 to 2000 The latter half of the 20th century centered around the standardization of diagnostic criteria for mental illness. The hallmark of this process was the publication of the American Psychological Association's Diagnostic and Statistical Manual of Mental Disorders (DSM). This foundational tool is still in use in modern psychology and helps direct diagnosis and treatment. 1952: The first "Diagnostic and Statistical Manual of Mental Disorders" is published. 1954: Abraham Maslow publishes "Motivation and Personality," describing his theory of a hierarchy of needs. Maslow is one of the founders of humanistic psychology. 1958: Harry Harlow publishes "The Nature of Love," which describes the importance of attachment and love in rhesus monkeys. 1961: Albert Bandura conducts his now-famous Bobo doll experiment, in which child behavior is described as a construct of observation, imitation, and modeling. 1963: Bandura first describes the concept of observational learning to explain aggression. 1968: The DSM-II is published. 1974: Stanley Milgram publishes "Obedience to Authority," which describes the findings of his famous obedience experiments. 1980: The DSM-III is published. 1990: Noam Chomsky publishes "On the Nature, Use, and Acquisition of Language." 1991: Steven Pinker publishes an article introducing his theories as to how children acquire language, which he later publishes in the book "The Language Instinct." 1994: The DSM-IV is published. 21st Century With the advent of genetic science, psychologists began grappling with the ways in which physiology and genetics contribute to a person's psychological being in the 21st century. 2002: Steven Pinker publishes "The Blank Slate," arguing against the concept of tabula rasa (the theory that the mind is a blank slate at birth). Avshalom Caspi offers the first evidence that genetics are associated with a child's response to maltreatment. Psychologist Daniel Kahneman is awarded the Nobel Memorial Prize in Economics for his research on how people make judgments in the face of uncertainty. 2003: Genetic researchers finish mapping human genes, with the aim of isolating the individual chromosomes responsible for physiological and neurological conditions. 2010: Simon LeVay publishes "Gay, Straight, and the Reason Why," which argues that sexual orientation emerges from prenatal differentiation in the brain. 2013: The DSM-5 is released. Among other changes, the APA removes "gender identity disorder" from the list of mental illnesses and replaces it with "gender dysphoria" to describe a person's discomfort with their assigned gender. 2014: John O'Keefe, May-Britt Moser, and Edvard Moser share the Nobel Prize for their discovery of cells that constitute a positioning system in the brain that is key to memory and navigation. Classic Psychology Experiments Modern Psychology Today Thanks to the contributions of the many experts along the way, the field of modern psychology has expanded into multiple subdivisions or specializations. Some of the numerous branches in modern psychology as it stands right now are: Abnormal psychology: Psychopathology and abnormal behavior Behavioral psychology: How behaviors are developed Clinical psychology: Assessment and treatment of mental disorders Cognitive psychology: How we think Counseling psychology: Treating clients in mental distress Developmental psychology: How people change throughout life Experimental psychology: Research of the brain and behaviors Forensic psychology: Psychology within legal settings Health psychology: How psychology influences health and illness School psychology: Psychology of children in educational settings Social psychology: Social influences on psychology 4 Sources Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Khalil RB, Richa S. When affective disorders were considered to emanate from the heart: The Ebers Papyrus. Am J Psychiatry. 2014;171(3):275. doi:10.1176/appi.ajp.2013.13070860 Macintyre I. The Monro dynasty and their treatment of madness in London. Neurosciences and History. 2015;3(3):116-124. Caspi A, McClay JL, Mill J, et al. Role of genotype in the cycle of violence in maltreated children. Science. 2002;297(5582):851-854. doi:10.1126/science.1072290 National Human Genome Research Institute. Human Genome Project timeline of events. Additional Reading American Psychological Association. 125th Anniversary APA Timeline. Shiraev E. A History of Psychology: A Global Perspective. 2nd ed. Sage Publishing. Suris A, Holliday R, North CS. The evolution of the classification of psychiatric disorders. Behav Sci (Basel). 2016;6(1):5. doi:10.3390/bs6010005 By Kendra Cherry, MSEd Kendra Cherry, MS, is a psychosocial rehabilitation specialist, psychology educator, and author of the "Everything Psychology Book." 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