‘When Dual Sensory Mode with Limited Text Presentation Enhance Learning’

Abstract

Advances in the knowledge of human memory suggest that under some circumstances, more processing capacity is effectively available to learners if instructional materials use multiple modalities (e.g. auditory for text and visual for pictures). According to cognitive load theory, some conventional approaches to instructional design are ineffective as they place an unnecessary load on a learner's working memory and cause learning to be hindered. Previous research, particularly in technically-based areas, has demonstrated that duplicating the same text in both visual and auditory formats may inhibit learning (audiovisual redundancy effect). However, it is not yet clear whether partial on-screen textual information (e.g., key words or phrases) presented simultaneously with fully narrated text would generate a similar negative effect or be beneficial for learning, especially when the language of instruction is a foreign or second language for the learners. Accordingly, the reported study examined whether supporting the narrated textual explanations of the related graphics in a visual form as key words or phrases would be more effective to learning in a realistic setting (and with English as a foreign language for the students) than the exact visual duplication of the narrated text. University students learned steps of psychosexual development since childhood up to adolescence period through audio text and graphics presented using PowerPoint slides and three different versions of the visual text: 1) the full text equivalent to the narrated explanations; 2) the reduced version of the text that presented phrases expressing major ideas in the text; and 3) key words representing main concepts. The pre and post- tests were conducted to evaluate levels of learner prior knowledge and post-instruction performance. The results indicated that the auditory explanations of the graphics supported by visual display of main phrases related to the explanations resulted in significantly better learning that either exact full visual duplication of the text or presenting only a limited number of key words. The study shows that supporting the audio explanations of graphics with visually presented on-screen phrases expressing main ideas of the text could be the most effective way of instructing learners for whom the language of instruction is a foreign or second language.