DURINGthe past decade, research in audio-visual communication has increased largely because of the research programs being conducted by the Armed Services, This 10-year period has also seen a changing research emphasis from the comparative study of different kinds of instructional technics and the attempts to justify the use of AV materials to the investigation of variables within the materials themselves and the methods of use in order to increase their instructional and persuasive effectiveness.Few general reviews of the research have been written since Stenius' article (140) of 1945. McClusky (92) analyzed the classical research, and Dale, Finn, and Hoban (33, 34) made a selective review of the literature to 1948. Bibliographies were compiled by the staff of the Instructional Film Research Program (25) and by Larson and Runden (86).Considerable evidence has accumulated on the effectiveness of AV materials as compared with conventional means of instruction and with other AV materials. This section will review the major studies comparing instructional technics,
Motion PicturesThe motion picture film research will be reviewed with three instructional objectives in mind: imparting a knowledge of facts; teaching perceptual-motor skills; and influencing motivation, attitudes, and opinions, which conforms roughly to the Hoban-VanOrmer pattern.Knowledge of Facts. The evidence during the past decade supported Hoban and VanOrmer's conclusion that films can teach factual information effectively over a wide range of subjectmatter content, age, abilities, and conditions of use. This factual learning, however, tends to be rather AUDIO-VISUAL MATERIALS tested, the investigators concluded that the film instruction increased teamwork and efficiency.Roshal (121) studied the effects of certain variables of learner representation on learning to tie knots and found (a) that a film is more effective if the task is portrayed from the viewing angle that would be assumed by the learner in performing the skill, and (b) that a presentation of the motions involved is more effective than presenting a series of static photographs. Two studies were made by Jaspen (72, 73) on the effects of a number of film variables on learning the assembly of the breech block of the 40mm antiaircraft gun by naval trainees. An experimental film was able to teach 98 percent of the men how to assemble the breech block. Jaspen concluded that a slow rate of development, the pointing out of errors to be avoided, the repetition of the assembly demonstration, and the participation by the learner in the performance of the task contribute significantly to the effectiveness of the film. Harby (50, 51) and Murnin, Hayes, and Harby (106) used the daylight projection of repetitive film loops in the teaching of such athletic skills as tumbling and basketball free-throw shooting. They found that a repeated motion picture demonstration was at least as effective as a live instructor's demonstration, but that the live instruction was superior when the technic of individual c...