Robert Yerkes: His Life and Contributions to Psychology

Table of ContentsView AllTable of ContentsBest Known ForEarly LifeCareerContributions to PsychologySelected Publications

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Table of Contents

Best Known For

Early Life

Career

Contributions to Psychology

Selected Publications

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Robert Yerkes (May 26, 1876 - February 3, 1956) was an American psychologist best remembered for his work in the areas of intelligence testing and comparative psychology. He is also known for describing the Yerkes-Dodson law with his colleague John Dillingham Dodson. The Yerkes-Dodson law suggests that there is a relationship between arousal levels and performance.

While Yerkes believed that the tests measured native intelligence, later findings revealed that education, training, and acculturation played an important role in performance.Intelligence testing in general has come under major scrutiny in recent years given its dubious foundational connections to racism.

Robert Yerkes grew up on a farm in Breadysville, Pennsylvania. He attended Ursinus College originally intending to become a medical doctor. After graduating in 1897, Harvard University offered him a spot doing graduate work in biology. During his studies at Harvard, he took an interest in animal behavior and began studying comparative psychology. In 1902, Yerkes earned his Ph.D. in psychology.

After graduating, Yerkes took a number of positions to pay the debts he had acquired while completing his education. He started as an instructor at Harvard, later getting promoted to assistant professor of comparative psychology, and taught courses in general psychology during the summer at Radcliffe College. He also took a part-time job as the director of psychological research at the Boston Psychopathic Hospital in Boston, Massachusetts.

In 1917, he was elected President of theAmerican Psychological Association. After the U.S. entered World War I, Yerkes urged the APA to get involved in contributing psychological expertise to the war effort. A number of committees were formed, including one designed to measure intelligence in order to identify Army recruits who were particularly suited for special positions.

Robert Yerkes contributed greatly to the field of comparative psychology. He founded the first primate research laboratory in the United States and served as its director from 1929 until 1941. The lab was later renamed the Yerkes National Primate Research Center.

His work with John D. Dodson led to the development of what is known as the Yerkes-Dodson Law. This law states that performance increases with arousal, but only up to a certain point. When arousal levels become too high, performance actually decreases.

A Mixed Legacy

Yerkes, R. M., Bridges, J. W., & Hardwick, R. S. (1915).A Point Scale for Measuring Mental Ability. Baltimore: Warwick & York.

Yerkes, R. M. (1916).The Mental Life of Monkeys and Apes: A Study of Ideational Behavior. Delmar, NY: Scholars' Facsimiles and Reprints.

Yerkes, R. M. (Ed.) (1921)Psychological Examining in the United States Army.U.S. Government Printing Office.

Yerkes, R. M. (1941). Man-power and military effectiveness: The case for human engineering.Journal of Consulting Psychology, 5(5), 205-209.

Yerkes, R. M. (1943).Chimpanzees: A Laboratory Colony. New York: Johnson Reprint Corporation.

2 Sources

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Yerkes RM, Dodson JD.The relation of strength of stimulus to rapidity of habit-formation.Journal of Comparative Neurology and Psychology.1908;18:459-482. doi:10.1002/cne.920180503Warne RT, Burton JZ, Gibbons A, Melendez DA.Stephen Jay Gould’s analysis of the Army Beta Test in The Mismeasure of Man: Distortions and misconceptions regarding a pioneering mental test.Journal of Intelligence. 2019;7(1):6. doi:10.3390/jintelligence7010006

Yerkes RM, Dodson JD.The relation of strength of stimulus to rapidity of habit-formation.Journal of Comparative Neurology and Psychology.1908;18:459-482. doi:10.1002/cne.920180503

Warne RT, Burton JZ, Gibbons A, Melendez DA.Stephen Jay Gould’s analysis of the Army Beta Test in The Mismeasure of Man: Distortions and misconceptions regarding a pioneering mental test.Journal of Intelligence. 2019;7(1):6. doi:10.3390/jintelligence7010006

Fancher, RE.The intelligence men: Makers of the IQ controversy.New York: W. W. Norton & Company; 1985.

Greenwood J.Psychologists go to war.Behavioral Scientist. Published May 22, 2017.

McGuire, F. (1994). Army alpha and beta tests of intelligence. In: Sternberg RJ, ed.Encyclopedia of Human Intelligence. Vol 1. New York: Macmillan; 1994:125-129.

Murchison, C (ed.). (1930).History of Psychology in Autobiography. Vol 2. Worcester, MA: Clark University Press; 1930:381-407.

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