Playing before Moana was the short Inner Workings, the Leo Matsuda-directed story about how every part of us has a different desire and goal. Mainly, the conflict is between the impulsive, pleasure-seeking heart, and the brain, which thinks everything will end in death. Now, we have concept art to help us look more closely at these organs.
First, some upset-looking intestines from Nick Orsi:
https://www.tumblr.com/nicholasorsi/153648396912/
And, also from Orsi, you can take a look at the brain, heart, kidneys, and full body.
Mike Yamada has shared some scene concepts and a full map of Paul, the man whose organs are yo-yoing him around:
From story artist Jeremy Spears are these wood carvings:
[via Cartoon Brew]