Cerebral cortex

A Weeping Angel, named "Angel Bob", took the cerebral cortex from the body of cleric Bob and re-animated a version of his consciousness to communicate with the Eleventh Doctor. (TV: The Time of Angels)

Behind the scenes

 * According to NOTVALID: Know Your Enemy, a TARDIS data extract suggested that the Lone Cyberman had a super-computer fused to his cerebral cortex.