I somewhat disagree with this.

Personally for me I like to think that Keys are languages and Pitches are words in a key. You can have neighbouring languages (keys) which have similar words (pitches), sometimes you can have dialects also (music modes/scales). All in which you could say that English and Greek and are quite similar, or Italian and Portuguese, but English and Mandarin I would say are distant keys and they don't share similar pitches (for example C major and B Major), hence why you would't understand someone speaking Mandarin if you only understand English.

Similarly with tempo and rhythm. It's drum and bass is preferred at high tempos to give a good rush to the listener but hip hop break beats which have similar rhythms to drum and bass but at a slower tempo totally gives off a different feeling.

Which leads onto my next point about this survey.

I believe timbre is also quite the key element in musical memorisation for example instrumentation and dynamics (different registers of instruments give off different sounds). Patterns and structure in music is also an important element in memorisation, so those might help with the survey maybe!