Decay, Interference, Forgotten Cues

According to Ultralearning, there are perhaps 3 mechanisms of forgetting:

  1. Decay - perhaps all memories just decay over time
  2. Interference - things that remind of you of the thing are crowded out by the same cues that now remind you of other things instead.
  3. Forgotten cues - you actually do have some memories locked away in your head, but the cue that gets you to that group of memories is gone. Suddenly you may rediscover that cue and all sorts of memories come flooding back.

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