With the rapid growth of multimedia in education, the importance of investigating the effect of redundancy, repeating instructional messages to enhance conceptualization in instructional material design, is becoming more important. Various studies have been conducted recently regarding the effects of different forms of redundancy. A multimedia lesson presenting concurrent on-screen text, still graphics or animations, and narration is a typical setting in redundancy research. Concise redundancy is the revision of the on-screen text into a concise form which is presented to the learners concurrently with visualizations and narration. The purpose of this study was to investigate, while controlling for spatial ability, the effects of concise redundancy on students' retention and confidence when learning with highly complex multimedia materials. In addition, the effects of animation or still graphics along with text redundancy were examined. No significant differences were found between the graphic presentations (animation or series of stills) and text redundancy groups (full, concise, or none) on retention or levels of confidence. When examining the results taking into account high and low spatial abilities, no significant differences were found in terms of different graphic presentation (animation or series of stills) and different text redundancy groups (full, concise, or none). However, in one condition, low spatial ability learners exhibited significantly higher levels of confidence than high spatial ability learners when learning with narrated static graphics and concise redundancy. The current study should provide further guidance for researchers who are interested in examining narrated multimedia lessons containing concise redundancy when comparing static graphics to animated graphics. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]