Split Attention Effect

A cognitive load phenomenon in multimedia learning where learners must divide visual attention between two or more sources of information that should be integrated - for example captions at the bottom of the screen and a diagram in the centre. The cost of switching and mentally integrating separated sources consumes working memory that would otherwise be available for learning. The effect is more severe for d/Deaf and Hard-of-Hearing learners, who cannot offload any of the sources to the auditory channel and must shift visual attention between captions, slides, speaker, and visuals.