One of the 4 techniques, associated with learning gain, used by the timely practice system - with the aid of the timely practice app.
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See the mp4 below on how timely practice applies Rohrer and Taylors' research
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and increasing interval retrieval practice or spaced repetition system (SRS) which explains Ebbinghaus' forgetting curve and how SRS makes use of this to improve learners' memories.
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"Since the spacing effect was first discovered by Ebbinghaus in 1885, research has consistently shown that learning performance improves if multiple study sessions are separated in time (or “spaced”) rather than massed together. The effect occurs for adults, pre-schoolers and infants, and primary and secondary school children. A brain imaging study suggests the spacing effect in verbal learning is due to enhanced maintenance rehearsal (i.e. additional thinking about the material) in spaced, relative to massed presentations."
https://v1.educationendowmentfoundation.org.uk/uploads/pdf/NSED_LitReview_Final.pdf (page 29 to 30)
More readable references
Review of "Make it Stick" The Science of Successful Learning
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