At Harvard, he continued his focus on experimental psychology, and took an interest in the nascent trend toward operationism.
[1] In 1930, he was awarded an eight-month Guggenheim Fellowship to pursue "investigations into the expressive properties of musical structure by means of methods which are being developed by the Gestalt psychologists in Germany.
During World War II, he served on the Committee for Military Psychology (a group organized by the Emergency Committee of the National Research Council), where he helped draw up psychological guidelines to test "the capacity of men required to man guns, sound detectors and other equipment.
[9][10] He was invited to Ankara by the Turkish Education Ministry and Muzafer Sherif (one of Pratt's former graduate students at Harvard University), and was the first visiting professor sent to Turkey under the auspices of the Department of State's Division of Cultural Cooperation.
[11][12] Upon returning to the United States, he was appointed professor of psychology at Princeton University, where he taught from 1947 to 1962.