Adjust how many interacting elements you introduce at once

Introduce concepts with high element interactivity only after prerequisite elements are automated.

Why it works

Cognitive load theory distinguishes "element interactivity" — the number of elements that must be held in working memory simultaneously because they interact. High interactivity material is intrinsically complex: you cannot understand it by processing elements sequentially. For novices, this is the primary source of overload. For experts, automated schemas handle interacting elements as single chunks, so high interactivity material ceases to be cognitively expensive.

How to do it

1. Decompose a complex topic into its elemental components and identify which interact and which are independent.
2. Teach independent elements first, ensuring each is automated before introducing interactions.
3. Introduce interacting pairs, then triplets, only after the individual elements are handled without load.

Evidence

Element interactivity as a determinant of intrinsic cognitive load is a core concept in cognitive load theory and is supported by studies showing that high-interactivity material is more difficult and that segmenting it improves learning for novices but not for experts. Sweller & Chandler (1994) grounds this empirically, tracing why some material is intrinsically hard to the number of elements that must be held and reconciled at once. (mechanistic)

Element interactivity is theoretical — it is inferred from learning difficulty rather than measured directly. Its role as the key variable in load is widely accepted but somewhat circular in operationalization.

Sources

• Sweller (1994), "Cognitive load theory, learning difficulty, and instructional design", Learning and Instruction
• Sweller, J. (1994). Cognitive load theory, learning difficulty, and instructional design. Learning and Instruction, 4(4), 295–312.
• Sweller, J., & Chandler, P. (1994). Why some material is difficult to learn. Cognition and Instruction, 12(3), 185–233.

Common mistake

Treating all difficulty as intrinsic and permanent rather than as a function of element interactivity that can be reduced by building prerequisite automation first.