Japanese can talk with their heads as well.

A cute video I once saw had a mother telling her daughter - in Japanese - “use your head” as the little toddler tried to work a box open. The little girl bent forward and started banging her head on the box.

The Japanese use the head in conversation often.

頭がいい[あたまがいい, atama ga ii] be smart; be quick, have a good head

A good head is one that works well = smart or just quick.

Smart in Japanese, said sumaato, is not the same. It means to be slender or thin and has nothing to do with one’s mental abilities.

I had a friend who tried to fake his way into speaking Japanese once, trying to impress his good Christian in-laws. He didn’t know how to say “give me the bill (for the food), so he said biiru wo kudasai. He didn’t get the bill and he didn’t impress his in-laws when the staff brought him a couple of beers.
So you would you rather be smart or smart?