memory drum

- source

• The memory drum is a psychological equipment for the study of cued memory, paired association, and serial learning, also known as a memory device. It was designed in 1894 by German psychologist Georg E. Müller and his student Frederich Schumann.
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• possible some Spaced Repetition (or alternative) analog spaced repetition stuff?
• see this is in 📝 Repetition and Spaced Review in the Learning of Connected Discourse:

  • It was considered that the teaching machine, in a manner similar to a memory drum, would permit control over such presentation variables as amount and order of material exposed

    • also in design and mechanics, seems somewhat similar to Skinner teaching machine