Isidore Gormezano was born on July 20, 1930, and graduated in 1948 from Stuyvesant High School, Manhattan, New York. He received the B.A. from New York University, University Heights College, in 1952. After serving in the Army Medical Corps in the U.S. Army from 1953 to 1955, he studied experimental psychology at the University of Wisconsin-Madison, where he received the M.A. in 1957. The following year he received the Ph.D. in Experimental Psychology at the same institution, with a minor in Mathematical Statistics.

From 1958 to 1966, he was a member of the faculty, starting as an instructor, at Indiana University at Bloomington. He attained the rank of professor by the time he completed his tenure at Indiana. On September 1, 1966, he was appointed professor in the Department of Psychology at the University of Iowa, where he remained for the rest of his academic career. In 1997, he was named The Kenneth W. Spence Professor of Psychology at Iowa.

His other teaching engagements included the University of California, Berkeley (visiting assistant professor, fall 1963 and winter-spring 1970), the University of Western Australia, Perth (distinguished visiting professor, fall 1975), University of California, Irvine (visiting professor, spring 1977), University of Miami, Coral Gables (visiting professor, spring 1990), and the University of New South Wales, Sydney (visiting professor, fall 1990).

Among I. Gormezano's many honors were the Pavlovian Investigator Award, The Pavlovian Society, for Distinguished Research Achievements (1992); The Howard Crosby Warren Medal, Society of Experimental Psychologists, for Distinguished Contributions to Experimental Psychology (1994); and a Founding Council Member of the I.P. Pavlov International Science Center, St. Petersburg, Russia (1993).