Caffeine and mental deficiency

Coca-Cola advert, c.1914The latest finding on the effects of caffeine in preventing memory loss among older women — which has been widely reported in the popular press (see e.g., BBC, CBCCBS, SciAm) — has an interesting parallel in the history of psychology: Harry Hollingworth’s study of caffeine for Coca-Cola in 1911.  This time, however, the direction and valence of the attention has been reversed.

Whereas caffeine now seems to be “good for you,” in 1909, the U.S. government seized 40 barrels and 20 kegs of Coca-Cola syrup because it was “bad.”  Part of the company’s defense strategy at the time was to hire Hollingworth, with his wife Leta Stetter Hollingworth as a paid-assistant, to examine the psychological effects of caffeine.  The resulting work has been upheld as an exemplar of experimental design.


  • Benjamin, L. T., Rogers, A. M., & Rosenbaum, A.  (1991).  Coca-Cola, caffeine, and mental deficiency: Harry Hollingworth and the Chattanooga trial of 1911.  Journal of the History of the Behavioral Sciences, 27(1), 42-55.

Harry Hollingworth’s 1911 investigation of the behavioral effects of caffeine is one of the earliest examples of psychological research contracted by a large corporation. The research was necessitated by a federal government suit against the Coca-Cola Company for marketing a beverage with a deleterious ingredient (i.e., caffeine). Although Hollingworth’s research played little role in the outcome of the Coca-Cola trials, it was important as a model of sophistication in experimental design by setting a standard for psychopharmacological research. It was also important in directing Hollingworth toward a life-long career in applied psychology.

See also:

  • Klein, A. G.  (2000).  Fitting the school to the child: The mission of Leta Stetter Hollingworth, founder of gifted education.  Roeper Review, 23(2), 97-103.

Discusses the achievements of L. S. Hollingworth regarding the teaching of gifted children. Born in Nebraska in 1886, Hollingworth was a psychologist, educator, and feminist. She was profoundly gifted. She smiled, imitated others, crawled, and used language far earlier than the average child, and she exhibited Dabrowskian overexcitabilities throughout her life. She is most remembered as the founder of gifted education. In 1922, Hollingworth initiated the Public School 165 Experiment, a 3-yr longitudinal study of gifted children in New York City. The collected data was a rich source for scholars. In 1936, Hollingworth initiated the Speyer School Experiment to teach gifted students using newly developed, student-centered curricula. The issues she identified and addressed are the very issues that continue to be debated and pondered in the profession, which include: identification of the gifted, the value of acceleration and enrichment programs, and mainstreaming issues.


About Jeremy Burman

Jeremy Trevelyan Burman is a senior doctoral student in York University’s Department of Psychology, specializing in the history of developmental psychology and its theory (especially that pertaining to Jean Piaget). Prior to returning to academia, he was a producer at the Canadian Broadcasting Corporation.