That a joke or ...?

So (one) research says (or at least someone summarized a research in the following way):

 

I guess what punchline I am tempted to formulate is almost too evident, but just for clarity I'd hint a bit more by stuffing a few words in:

Individuals with higher (non-verbal) intelligence test scores are more likely to prefer predominantly instrumental (i.e. non-verbal) music styles.

Hm... :) doesn't it smell like a tautology creeping in softly?

I'm not saying the finding may not be correct though.

Anyway, here's a bit of Iron Maiden just in case you missed it ;)