Cerebration Mentor

The Cerebration Mentor (also known as a Cerebraton Mentor) was device capable of generating emotional impulses.

Its inventor, Professor Watkins, originally devised it as a sophisticated teaching aid. When the Cybermen learned of its existence, they asked their ally, Tobias Vaughn, to destroy it. However, Vaughn, eager to use it as a weapon against the Cybermen, kidnapped Watkins and forced him to perfect the device.

Although Vaughn was prevented from mass-producing the Mentor, he ended up using Watkins' prototype against the Cybermen. (DW: The Invasion)

The Cerebration Mentor can put emotions into a Cyberman, namely fear into a particularly unlucky Cyberman, causing it to go mad with fear.