Mind Analysis Machine

During the Time Paradox Incident, Daleks operating on Earth in an alternate timeline used a Mind Analysis Machine to forcibly ascertain the identity of the Third Doctor, which was done when the familiar images of the First and Second Doctors were projected on their screen. (PROSE: Doctor Who and the Day of the Daleks, TV: Day of the Daleks)

The device was similar in practice to the Time Lords' Thought Channel, which was used at the request of the Second Doctor to present the "evil" he had fought against in his trial. (TV: The War Games)

Scrutinising Dalek history, the Time Lords were aware (PROSE: Dalek Combat Training Manual) that the mind analysis machine was designed to elicit information from uncooperative subjects. It was not especially effective against those with a strong will, however, and would practically kill such an individual in the process of retrieving even basic information. (TV: Day of the Daleks) This technology was later refined as an interrogation machine which could be used effectively to determine the veracity of answers given by a prisoner. (PROSE: Doctor Who and the Destiny of the Daleks, TV: Destiny of the Daleks) It also led to the creation of a duplication machine that could display the memories of a given subject on a monitor and create a copy of their mind to be implanted into a Dalek duplicate. (TV: Resurrection of the Daleks) Later still, specialised units were adapted so that thought patterns could be read by bringing the skull into contact with the Daleks' suction cups. (TV: Doomsday, Daleks in Manhattan)

Behind the scenes

 * A section from the contemporary closing title sequence appears in the background on the screen of the Daleks' mind analysis machine at the end of episode three. The title sequence imagery was removed in the Special Edition, which also used different images of the First and Second Doctors.
 * The mind analysis machine sequence represented the first occasion that images of William Hartnell or Patrick Troughton had appeared in the show since their departures from it (with the exception of the image of Hartnell when the Second Doctor looks into the mirror in The Power of the Daleks). The next occasion they were seen on-screen (and the only other occasion this occurred in the Pertwee era) was when they both guest starred in The Three Doctors.
 * The use of the Mind Analysis Machine was parodied in an installment of Doctor Whoah!, where the Doctor is flustered as his mind wonders toward a romanticised image of the Brigadier in his underpants, and he tries to convince the Daleks that it is nothing more than "a brilliant fiction" he concocted to distract them.