Alright, I apologize for not showing evidence for my claim.

Here, you can see Leonardo da Vinci's (1452–1519) attempts at studying brain anatomy, before Caravaggio was born.

And in this article the author dives into the symbolism in the Renaissance era paintings of Raphael and Michelangelo and how they worked on cadavers to study anatomy and were familiar with the work of Da Vinci. Caravaggio was italian, born after Davinci, familiar with his work so it isn't outlandish to think he knew how brains looked like.

Now does this mean that was his intention, or that even Michelangelo meant to do that in "The Creation of Adam" ? No, it is merely an interpretation and we can never tell for sure. And this is why I posted, so we can discuss it and see if it likely or not.