<P> It is mentioned that the TARDIS assists the Doctor during the regenerative process, as suggested by the Second Doctor's statement to this effect shortly after regenerating from the First . This is reiterated by Jack Harkness' insistence that the Doctor be taken into the TARDIS having been shot by a Dalek in "The Stolen Earth". Of the six occasions on which the Doctor has regenerated outside the TARDIS: one is forced on him by the Time Lords (Second to Third Doctor, The War Games); one requires a Time Lord to give the Doctor's cells a "little push" to start the process (Third to Fourth, Planet of the Spiders); one results in his being dependent on the TARDIS's "Zero Room", a chamber sealed from all outside forces, to help him recover (Fourth to Fifth, Castrovalva); one occurs a few hours after he has actually "died" (Seventh to Eighth, the 1996 television film; the delay at is, however, shown to have been caused by anaesthetic, rather than the Doctor's distance from the TARDIS); one is induced by the Sisterhood of Karn after reviving the Doctor from actual death (Eighth Doctor, "The Night of the Doctor"). The Seventh to Eighth regeneration remains the only one that takes place significantly far away from the TARDIS, without any obvious interaction from other Time Lords and results in the Doctor suffering near - complete amnesia for nearly a day until an event inside the TARDIS triggers his memories to return . The future Eleventh Doctor is killed in mid-regeneration, showing he is vulnerable to death while regenerating and as such his need for the TARDIS may be for safety rather than aid . However it is later revealed that this regeneration was indeed a simulation since the Doctor who was shot was actually a Teselecta robot . The Eleventh Doctor starts his regeneration outside the TARDIS though he does end it inside it . In the case of the Twelfth Doctor, he briefly begins his regeneration after being electrocuted by a Mondasian Cyberman away from the TARDIS, but holds it off . When his actual regeneration starts, he emerges from the TARDIS as he struggles to hold it back . When the Twelfth Doctor finally does regenerate, it is within the TARDIS . As the Doctor contemplates his regeneration, the TARDIS appears to make its opinion on the matter known by flashing its lights at the Doctor, eliciting a response from him . </P> <P> The exact mechanism that makes regeneration possible is not stated in the television series, but it is generally assumed in the spin - off media that the ability to regenerate may be linked to what is known as the "Rassilon Imprimatur", the symbiotic nuclei of a Time Lord that bonds him or her to a TARDIS, and allows his or her body to withstand the molecular stresses of time travel (The Two Doctors, 1985). </P> <P> In "The Christmas Invasion" (2005) it is stated that the regenerative cycle generates a large amount of energy that suffuses the Time Lord's body, and also shown that residual effects from a regeneration allow him to grow back a hand within the first 15 hours after the initial start of the regeneration . Accordingly, in "Let's Kill Hitler", River Song is able to repel bullets after regenerating . She is later able to send off an energy wave soon after her regeneration, though this particular feat may be one of the abilities gained during the first 15 hours after a regeneration . </P> <P> In the series four finale of the revived series, "Journey's End", an injured Tenth Doctor manages to avert a full regeneration by channelling "excess regenerative energy" into his severed hand, allowing him to heal without changing form . The limb ends up developing into a half - human clone when Donna Noble touches it; the event, a "two - way" "Human - Time Lord Meta - Crisis", also gives Donna a Time Lord's mind . </P>

Does the doctor have a new set of regenerations