Before revision: Experiments Between the 1950s and the early 1960s, the Center conducted and experiment that compared students' knowledge of preliterate language after a lecture, seeing a videotape, hearing an audiotape, or reading the effectiveness of TV, radio, lectures and print in learning.
After revision: Experiments Between the 1950s and the early 1960s, the Center conducted and experiment that compared the effectiveness of TV, radio, lectures and print in learning.