The American psychologist Carl I. Hovland (1912-1961) was one of the pioneers in research on the effects of social communication on attitudes, beliefs, and concepts.

Carl I. Hovland was born in Chicago, III. He attended Northwestern University and completed his graduate studies at Yale University, receiving his doctorate in 1936. He then joined the faculty at Yale, where he remained throughout his entire career.

During the late 1930s and early 1940s Hovland made major contributions to several areas of human experimental psychology, such as the efficiency of different methods of rote learning. From his close association with Clark L. Hull and other psychologists working at the Yale Institute of Human Relations, Hovland developed a comprehensive view of the behavioral sciences that led him to extend the analytic experimental approach of research on human learning to underdeveloped areas of research in the human sciences.

Hovland's first opportunity to work intensively in the underdeveloped area of social psychology arose during World War II, when he took a leave of absence from Yale for over 3 years to serve as a senior psychologist in the War Department. His main role was to conduct experiments on the effectiveness of training and information programs that were intended to influence the motivation of men in the American armed forces. He assembled a group of six psychology graduate students who worked with him on these studies for several years. One of the most widely cited of the pioneering experiments on opinion change by Hovland and his group involved testing the effects of a one-sided versus a two-sided presentation of a controversial issue. The results contradicted contentions of totalitarian propagandists, who claimed that a communication that presents only one side of the issue will generally be more successful than one that mentions the opposing side of the argument. These wartime studies were reported in Experiments on Mass Communication (1949), written jointly by Hovland, A. A. Lumsdaine, and F. D. Sheffield.

After the war Hovland returned to Yale University, where he recruited several members of his wartime research team, with whom he continued to study the factors that influence the effectiveness of social communications. Among Hovland's best-known studies are those elucidating the influence of the communicator's prestige and the ways that prestige effects disappear with the passage of time. For example, Hovland and his collaborators showed that when a persuasive message is presented by an untrustworthy source, it tends to be discounted by the audience, so that immediately after exposure there is little or no attitude change; but then, after several weeks, the source is no longer associated with the issue in the minds of the audience and positive attitude changes appear. This delayed, or "sleeper," effect was shown to vanish, as predicted, if the unacceptable communicator was "reinstated" several weeks later by reminding the audience about who had presented the earlier persuasive material.

For 15 years Hovland and his group systematically investigated different ways of presenting arguments, personality factors, and judgmental processes that enter into attitude change. While pursuing his own research, Hovland continually encouraged his associates on the Yale project to select other problems in line with their own research interests. The work of Hovland's program was described in Communication and Persuasion (1953) by Hovland, Irving L. Janis, and Harold Kelly.

In the last decade of his life Hovland's research on verbal concepts and judgment led him into an intensive analysis of concept formation. Once again he played a pioneering role in developing a new field of research--computer simulation of human thought processes.

Further Reading

• A summary of the research developments and theoretical ideas that have grown out of Hovland's pioneering projects is presented in a comprehensive chapter by Irving L. Janis and M. Brewster Smith in Herbert C. Kelman, ed., International Behavior (1965). Hovland's work is also discussed in Arthur R. Cohen, Attitude Change and Social Influence (1964).