endocast

/ˈɛndoʊˌkæst/
noun
  1. A cast or model of the inside of a hollow object, especially the inside of a skull, used to study brain shape or structure.
    • Scientists made an endocast of the ancient skull to learn about the brain size.
    • By studying an endocast, researchers can estimate the intelligence of extinct species.
    • The museum displayed a 3D-printed endocast of a dinosaur brain cavity.