The use of subtitles within multimedia presentations is a common practice to develop accessible instructional materials for individuals with disabilities. However, due to various deficits in cognitive processing, individuals with symptoms of attention-deficit/ hyperactivity disorder (ADHD) may not benefit from the use of subtitles to enhance their recall of information and transference of knowledge with reduced mental effort. This study evaluated learners in two different environments. The redundancy group included subtitles with a narrated multimedia presentation, and the nonredundancy group included the same presentation with narration only. The analysis of data collected indicated that an increase in ADHD symptoms resulted in an increase in mental effort and a decrease in recall and transfer. Based on these observations, designers should allow learners to control the use of subtitles in narrated multimedia presentations.