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2 references
Bjork and Bjork explain why conditions that improve immediate performance can produce weak long-term learning, while conditions that introduce manageable difficulty can strengthen retention and transfer.
Desirable difficulties trigger encoding and retrieval processes that make memory more durable and flexible. Examples include spacing rather than massing practice, interleaving related categories or problem types, varying conditions of practice, and requiring generation or retrieval instead of repeated presentation. These methods often feel less fluent and produce more errors during acquisition, so learners and teachers may misjudge them as ineffective. The adjective desirable is essential: a challenge helps only when learners have enough prior knowledge and support to respond productively.
For educators, the chapter recommends evaluating methods with delayed, transferable performance and calibrating difficulty to the learner rather than equating smooth practice with lasting learning.
Bjork and Bjork explain why conditions that improve immediate performance can produce weak long-term learning, while conditions that introduce manageable difficulty can strengthen retention and transfer.
Desirable difficulties trigger encoding and retrieval processes that make memory more durable and flexible. Examples include spacing rather than massing practice, interleaving related categories or problem types, varying conditions of practice, and requiring generation or retrieval instead of repeated presentation. These methods often feel less fluent and produce more errors during acquisition, so learners and teachers may misjudge them as ineffective. The adjective desirable is essential: a challenge helps only when learners have enough prior knowledge and support to respond productively.
For educators, the chapter recommends evaluating methods with delayed, transferable performance and calibrating difficulty to the learner rather than equating smooth practice with lasting learning.
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From sources to a coherent pathway