Synergy between occlusion tests and neural review

Video

Showing improvements to occlusion tests and neural review in SuperMemo 19.

Video: Learning the anatomy of the hippocampus with occlusion tests and neural review in SuperMemo 19

This text and video are used to explain SuperMemo, a pioneer of spaced repetition software since 1987. For other videos see: SuperMemo Video

Highlights

• Occlusion tests in SuperMemo 19 (hippocampal anatomy)
• Learning statistics (several cloze deletions per minute, 97% retention)
• Neural review (CA1 + pattern)
• Creative outcomes (see bottom)

Summary

The process of learning brain anatomy, specifically the hippocampus, involves researching and finding a good diagram, and using incremental reading to generate elements for general understanding, with 96 elements created in 15 minutes 00:32.

To learn the graphical part, a template item is prepared, and occlusion tests are used to learn labels on the anatomical diagram, with the question "What structure is covered with the red rectangle?" 01:09.

The learning process involves using SuperMemo to generate occlusion test items, and reviewing the material, with the goal of achieving perfect memorization, resulting in 108 items and Retention of 97% (est. on Day #8) 06:22.

Details

• 00:00 The video demonstrates an improvement in learning graphic information in SuperMemo using occlusion tests. The presenter begins by preparing materials for learning brain anatomy.
• 00:15 A diagram is sourced from a scientific paper, enhanced with custom inscriptions, and supplemented with an AI-generated educational bulleted description for clarity.
• 00:32 Incremental reading generates 96 elements in 15 minutes to build a general understanding of the hippocampus, including questions about structures and functions.
• 00:50 General questions about hippocampal structures ensure a foundational understanding before starting graphic learning.
• 01:09 The presenter prepares a template item for occlusion tests ("What structure is covered with the red rectangle?") to learn labels on an anatomical diagram.
• 01:24 Occlusion tests are initiated via the Commander (Ctrl+Enter), targeting structures like Schaffer collaterals, mossy fibers, and the entorhinal cortex.
• 02:09 Additional structures (e.g., subiculum) and pathological changes are considered for inclusion in the occlusion tests.
• 02:42 A single occlusion test item is generated for each red rectangle, with answers like "Schaffer collateral."
• 02:57 The process is slow due to complex components but produces items like "What structure is covered with the red rectangle?" with answers such as "mossy fibers."
• 03:19 The presenter grades responses (e.g., mossy fibers) and considers omitting the answer field from the template for simplicity.
• 03:41 Some occlusion test questions (e.g., medial vs. lateral) are too easy, prompting the creation of a new "Point to..." template to increase difficulty.
• 04:00 A new test type ("Point to Lateral") is created for structures like C1-C4, using Shift+Alt+L to test and learn.
• 04:32 The "Point to lateral" test is demonstrated, with the presenter confirming the correct location and adding "lateral" for reinforcement.
• 05:01 A "Point to CA3" test is shown, with the presenter locating CA3 and adding the label for fun.
• 05:37 The slowness is attributed to fully functional components, which allow size adjustments or deletion to focus on key structures.
• 06:03 SuperMemo manages 120 components efficiently, storing the image only once to avoid disk pollution.
• 06:22 The final outcome includes 23 occlusion tests (e.g., "What structure is covered with the red rectangle?" and "Point to...") plus incremental reading material.
• 06:46 After a week, the knowledge is perfectly memorized, with 108 items, a 5.8% forgetting index, and 97% retention.
• 07:12 Repetition stats: 1.97 repetitions per item, 10-day intervals (shortened for demonstration), and a 2.9% last repetition forgetting index.
• 07:37 Most items are scheduled for May/June, with intervals up to 50 days and up to five repetitions, especially during neural review.
• 07:57 Lapses stem from poor initial formulations; some items (e.g., Schaffer collaterals) benefit from complete answers to avoid confusion.
• 08:20 Redundant items (e.g., "medial" visible on the image) are deleted to clean up the collection.
• 08:38 Further cleanup removes poorly formulated items retained for demonstration.
• 08:58 The memorized structures form a mental framework, enabling new conclusions about memory circuits (e.g., pattern separation, CA1 cells).
• 09:14 Neural review is planned to explore CA1 and pattern-related concepts, searching for "CA1" and "pattern" in the collection.
• 09:38 A neural review (Ctrl+F2) uncovers valuable articles on CA1 place cells and memory consolidation.
• 10:03 An article on CA1 place cells during sleep is prioritized for extraction due to its relevance.
• 10:29 A "monumental" finding links CA1 place cells’ correlation patterns during sleep to awake states, enhancing understanding.
• 10:53 The occlusion tests’ mnemonic structure amplifies the impact of neural review findings on learning and sleep.
• 11:08 The structural knowledge from occlusion tests makes neural review findings (e.g., cholinergic suppression) more meaningful.
• 11:30 Occlusion tests build a mnemonic foundation, transitioning to creative neural review for deeper insights into memory consolidation.

FAQ

Why blurry images?

• Q: How do you import high quality images? When I try to do it from textbook pdf, I get blurry images. Also is occlusion testing present in version 18 of SuperMemo?
• A: To avoid compressing images, you need to import them directly from the disk. SuperMemo always tries to save space. Perhaps in the future it can be disabled with a flag as huge disks are now a norm, and new generations hate lossy compressions. Occlusion has been available since 2000 (there is a video at supermemotheater), but it always used to be incremental. Only version 19 allows of generating items in bulk as in the presented video.

Massive review may violate 20 rules?

• Q: High priorities and short intervals (as in the video) seem like tool for crammers. Is that ok in the light of 20 rules? (see this video)
• A: Massive occlusion may be a tool for crammers or a tool for a passionate learning. The old incremental approach to occlusion is rational, but turns out deficient in working with complex structures, esp. if they are a top-priority framework for further learning. For a top priority diagram that is difficult to assemble in memory, you can launch a massive review at the start to build a coherent mnemonic memory structure. You can then keep adding new layers of knowledge incrementally and consolidate the structure with long-term benefits for retention and coherence. Density of review at first stages is beneficial in such cases. This gives you a chance to find "glue" as presented at 8:57 in the video ("generalization micro-circuit"). This comes from 20 rules: "Understand before you memorize"

Why complex terminology?

• Q: The hints on the buttons are impossible to understand. You should check Anki terminology! (see this video)
• A: We can use Anki wording in hints. However, there are just 2 main buttons to try. A frequent user is not likely to struggle
• Comment: See propositions by AI: Optimizing hints for occlusion tests

Outcome (Example)

The hippocampal circuit from Dentate Gyrus (DG) to CA3 to CA1 facilitates pattern separation, completion, and memory formation. DG orthogonalizes similar inputs, reducing overlap and enhancing pattern separation. CA3's recurrent network allows pattern completion through auto-association, recalling original memories from partial cues. CA1 integrates information from CA3 and sends output to cortical areas for memory formation. With consolidation, a shortcut develops from Entorhinal Cortex to CA1, enabling efficient recall of familiar information and bypassing the trisynaptic circuit.