John Sweller is an Australian educational psychologist whose cognitive load theory provides the empirical foundation for principles like “one idea per section” and “concrete before abstract” in instructional design.
Core ideas
- Cognitive load theory: working memory is limited — it can hold roughly 4–7 elements at a time. Instructional design should minimize extraneous cognitive load (processing caused by poor design) so learners can devote working memory to intrinsic load (the complexity of the material itself) and germane load (the effort of building understanding) [@sweller1988].
- Worked example effect: studying worked examples is more effective than solving equivalent problems, because examples reduce extraneous load. This grounds the vault’s emphasis on worked examples before exercises in lesson design.
- Split attention effect: when related information is separated (a diagram on one page, its explanation on another), learners must mentally integrate them, consuming working memory. Integrating information spatially reduces load.
Notable works
- “Cognitive Load During Problem Solving: Effects on Learning” (1988)
- Cognitive Load Theory (2011, with Paul Ayres and Slava Kalyuga)
Related
- readability — cognitive load theory explains why readability matters beyond surface features
- designing effective lessons — the vault’s lesson design draws on cognitive load principles