seems the script writers got two different (but possibly similar sounding) types of mnemonic confused.
an example of remembering something associatively might be - say for example I am trying to remember the artist of a painting I like but it isn't coming to mind. I think of the information i do know (movement, other artists, time period) in order to trigger the memory.
about roman room - which is what watson is describing
(imagining a house or place and depositing bit of info/memory there:
about using mind mapping (a way to memorize and then retrieve associatively)
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