Horizontal Decalage:

Noun:

The horizontal decalage refers to the difference in cognitive development between the diverse domains of a child’s abilities when progressing from one stage to another, particularly during the learning process.

In detail:

Horizontal decalage suggests that developmental changes don’t occur uniformly across all areas of a child’s knowledge or skills. Instead, there is often a discrepancy in the acquisition of abilities within the same developmental stage. This phenomenon suggests that children don’t progress at the same pace in all areas and might develop certain skills earlier or later than others, even within the same stage of development.

Example:

For instance, when children learn language, they might first develop basic vocabulary related to objects before mastering more complex grammatical structures. Similarly, in mathematical development, children might understand addition concepts before grasping multiplication or division. This discrepancy within stages demonstrates the concept of horizontal decalage.