One thing that could be helpful here is some external test of the vividness of your mental imagery. Is, for example, drawing a scene from memory known to be such a test? (I guess you'd have to get good at drawing first, but that might help with the imagery stuff too.)
Great idea about an external test. But I'm very, very bad at drawing things that look like real things.
This is the public group instrumental rationality diary for July 16-31.
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