By Stacey Brantley


In 1958, Jean Berko Gleason published ‘The Wug Test’, a landmark study that is considered to have laid the foundation for the modern study of linguistics.  The test was used to determine whether children between the ages of four and seven could extend the rules of English morphology on their own by adding morphemes to make nouns plural, make verbs past tense or nouns possessive.  By using imaginary animals and nonsense words that Gleason herself created, she has been able to demonstrate that children have a tacit understanding of language and are able to produce words they have never heard before and therefore could not have memorized.

How the basic Wug Test is conducted:

Children are shown the picture card reproduced above.  The experimenter points to the picture and reads the text.  The child should supply the missing word.

Following the publication of the study, there were those who claimed that the results proved Noam Chomsky’s theory that human language is coded in the genes and that we are genetically programmed to acquire and use language. Connectionists and linguists disagreed and attempted to find other explanations for interpreting the results, such as exposure, appropriate examples, higher order rules (abstractions and algorithms) and analogies.

Gleason puts herself somewhere in the middle of the two camps terming herself an Interactionist.  She believes that we are born with a certain capacity for language but that ultimately language is acquired through interaction with other people talking to us.  In a 2011 interview with ETJ Journal, she stated, “You can also view the Wug test results as evidence that children have the ability to abstract and generalize as part of their all purpose cognitive armamentarium, or you can think that the results are more evidence that language is a separate faculty, because what children are doing linguistically seems so much more sophisticated than their other cognitive attainments.”

Five decades later, the Wug Test is still a standard in children’s linguistic testing and Gleason, who is Professor Emerita of Psychology at Boston University, continues her research into language acquisition.  She has also done work on aphasia, with focus on lexical retrieval.

If you would like to listen to an interview with Jean Berko Gleason or take The Wug Test yourself  click here.


Berko Gleason, Ph.D., Jean. Home page. N.p., Web. 20 Apr. 2014.

Berko, J. (1958). The child’s learning of English morphology. Word, 14, 150-177. Extracted from Carnegie Mellon University childes.psy.cmu.edu/topics/ Web. 20 Apr. 2014.

Harkins, Dan. “What is The Wug Test.” Wisegeek.com. Conjecture Corporation.16 Mar. 2014. Web. 19 Apr. 2014.

“Jean Berko Gleason – Unfolding Language, Unfolding Life.” Narr. Krista Tippett. On Being. American Public Media, 3 Jan. 2013. Web. 18 Apr. 2014.

Love, Jessica. “What Toddlers Know They Don’t Know About Plurals.” The American Scholar. Phi Beta Kappa. N.d. Web. 19 Apr. 2014.

Murphy, Robert, S. “The Wug Test and Major Developments Since Then: The Jean Berko Gleason Interview.” ETJ Journal. Vol. 9. Issue 1. ISSN: 1883-0099. (2001). N.pag. Web. 18 Apr. 2014.

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