Effects of Preparatory Communications on Reactions to a Subsequent News Event

Abstract

Due to opportune circumstances, it was possible to investigate experimentally the way in which a preparatory communication influenced reaction to a later event. In June 1949 opinion measures were obtained one week before and one week after exposure to an “optimistic” communication which took the position that Russia would not be able to produce a stock pile of atomic bombs for a long time to come. Follow-up measures from experimental and control groups were obtained three months later—a few days after President Truman announced that an atomic explosion had taken place in the Soviet Union. The results consistently indicate that the “optimistic” communication had the effect of producing “resistance” to the impact of the subsequent event: following the September announcement the experimental group showed significantly less change in the pessimistic direction than did the control group in their opinions about Russia's future A-bomb supply and the imminence of war. Alternative hypotheses regarding the effects of preparatory communications are also explored in this article.