ABSTRACT
In 1970, Tichenor, Donohue, and Olien published a programmatic study of the social structure of public affairs and science knowledge entitled “Mass Media Flow and Differential Growth in Knowledge.” By that time more than 20 years of mass communication effects research had implicitly demonstrated “the apparent failure of mass publicity to inform the public at large,” with the particular fi nding that media campaigns tend to reach precisely those “least in need of it… [whereas] those missed were the ones the plan tried to reach” (1970, p. 161). They argued, however, that this outcome was no mere “failure” of an information campaign, but rather the product of the social structure of mass communication. Terming this effect the knowledge gap, they formulated a hypothesis, a set of assumptions, explanatory factors, and a pair of testable statements that could explain-and perhaps even help alleviate-this relative deprivation of knowledge between social strata.
