CHAPTER SEVENTEEN
Getting to the Hearts of Time Lord Personality Change: Regeneration on the Brain
SARITA J. ROBINSON
“We all change, when you think about it, we’re all different people….”
—Eleventh Doctor1
“A musician must make music, an artist must paint, a poet must write, if he is to be ultimately at peace with himself. What a man can be, he must be.”
—–psychologist Abraham Maslow2
Neuropsychology is a rapidly developing field of psychology which has started to reveal how the human brain works. Advances in techniques such as neuroimaging have given us windows on the brain that scientists from previous generations did not have. By comparing our understanding of human neuropsychology to an alien such as the one we know as the Doctor, we may be able to explore how his alien brain works and even speculate about the mechanisms involved in the process of regeneration.
Is the brain of an extraterrestrial similar to that of a human? In addition to having many physical differences from humans, most noticeably his binary vascular system with its pair of hearts, the Doctor has some cognitive (mental) differences. He processes information from books and computer systems much quicker than is possible for a human and appears to have a certain level of telepathic ability.3 These differences show us that Time Lords are both physically and psychologically different from humans.
Brain Scans and the Doctor
Does size matter when it comes to your brain? Logically, if someone has a bigger brain, you could expect that person to be more intelligent. However, this does not seem to be the case. One of the greatest scientists of the twentieth century, Albert Einstein, actually had a smaller brain than the typical adult male. After his death, his brain was examined, and some structural differences were observed. For example, Einstein had a larger than average left parietal lobe.4
So even though the Doctor might be assumed to have a human-size brain (based on the size of his skull), it could be that the Doctor’s brain is structured differently.
Or could it be that the Doctor uses more of his brain? Because humans use only 10 percent of their brains, right?
Wrong!
Although it is a popular myth that we only use 10 percent of our brain power, it is actually untrue.5 People who have even small amounts of brain damage can have major impairments in the way they function. All the parts of the brain are important, with each area responsible for a particular function. Take the occipital lobes (located at the back of the brain), for example; this area is responsible for visual processing. If a brain scan reveals damage to the occipital lobes, we would expect that person to have problems with his or her vision. But using our occipital lobes for processing visual information is only one of the things we do during a typical day. Humans tend to multitask, and so we must use various areas of our brains for all the different activities we undertake. Even if we just go walking in the park on a summer’s day, we will use visual and auditory processing to enjoy the sights and sounds, balance, and other motor skills required to walk. Next, the language-processing areas of the brain would be activated to produce (Broca’s area) and understand (Wernicke’s area) speech if we stop for a chat.9
Not until the early 1900s was it possible to look at the brain of a living person. The earliest technique, pneumoencephalography, was both dangerous and painful.6
After the 1940s, improvements in surgical techniques allowed brain surgeons to carry out operations that could alleviate conditions such as epilepsy. One neurosurgeon, Wilder Penfield, used an electrical probe during those operations to stimulate parts of the brain and then recorded which functions each part of the brain controlled. For example, an electric current in the temporal lobes caused patients (who were kept awake through surgery) to summon past memories.7
The Doctor is unlikely to have brain surgery just so that we can poke around in his head. However, a technique called functional magnetic resonance imaging (fMRI) allows us to see how different experiences change blood flow and oxygenation levels in the brain, letting us see which areas the brain uses for certain functions.8 Brain imaging has definitely come a long way in the last 100 years, but further advances are needed as the equipment is cumbersome and expensive.
As the Doctor appears to be quite psychologically different from us, we have to conclude that his brain must be structured differently. The only way to confirm this would be to do a brain scan. Although some enemies try to steal the Doctor’s head,10 they do not manage to complete scans of his brain.11 Here on Earth we don’t have the benefits of alien technology, and until recently the only way to look into someone’s brain was to cut open the skull, as the sidebar “Looking into Skulls” explains.
What Happens to the Doctor’s Brain During Regeneration?
During regeneration, the Doctor undergoes a rapid change in his physical appearance as the cells in his body are renewed. He also appears to show changes in his psychological makeup. Although the Doctor can retain his previous memories, the changes in his personality can be as marked as the physical changes. We also know that the process of regeneration can be difficult and painful, leading to emotional upset and physiological problems. In fact, some of the Doctor’s behaviors around the time of regeneration are similar to those seen in teenagers. Any parent of a teenager can tell you that the adolescent years are a period of emotional, cognitive, and biological changes. In the Doctor’s case, his transformation appears to be compressed into an acute phase lasting a few hours, followed by a longer period of recovery.12
Psychologists think that at around age twelve, individuals begin a process called synaptic pruning13 in which the neural connections that are not being used start to die off. For example, if a second language is learned early in life but not used in later years, during adolescence these language connections may be cut. It could well be that the Doctor, around the time of regeneration, undergoes an extreme form of synaptic pruning. In the case of the Doctor, it would appear that he has some control over which synaptic links to keep. Just as the process of synaptic pruning gets a teenager ready for adulthood, the process of regeneration may make the Doctor’s brain ready for the challenges he will face in his next regeneration. For example, we know that when the Eighth Doctor regenerates into the War Doctor, he actively regenerates into a form that will be able to face the challenges of the Time War.14
During adolescence the process of pruning can go wrong and lead to psychiatric disorders such as schizophrenia, a long-term disorder that can impact how a person thinks, feels, and behaves.15 It is possible that the Doctor could similarly face the problem of abnormal synaptic pruning following regeneration. The Doctor’s regeneration into the Sixth Doctor is especially problematic, with the Doctor appearing unstable and difficult, as demonstrated most dramatically when he attempts to strangle his companion, Peri, in the hours after his regeneration.16 It is possible that the violent and traumatic event of regeneration can lead to errors in synaptic pruning which take time to resolve.
Interestingly, neuroscientists now believe that the brain can continue to change and be shaped for the challenges we meet even after the teenage years. For example, brain regions involved in the recall of spatial information have been shown to change when London taxi drivers learn “The Knowledge” (the layout of all the roads in London).17 Specifically, taxi drivers had different neural architecture in an area of the brain well known for being important for memory: the hippocampus. So how does the process of regeneration affect the Doctor’s brain, and can we guess the possible structure and neurochemical balance of the Doctor in each of his regenerations?
Neophrenology
If no one has taken a picture of the Doctor’s brain, can we make any predictions about what it might look like? In the nineteenth century, the study of phrenology suggested that the external shape of the skull could be used to ascertain certain characteristics about a person. For example, if a person had a particular bump above his or her right eye, that would tell you something about that person’s sense of humor. Phrenology has been thoroughly discredited, but some contemporary neuropsychologists have coined the phrase neophrenology.18 Neophrenology suggests that by looking at a person’s brain structure, you may be able to predict differences in his or her mental abilities. Using this reasoning, we should be able to reverse engineer what the Doctor’s brain looks like by examining some of the behaviors he displays. The Doctor’s brain may look quite different in each regeneration, dependent on the particular skills and abilities peculiar to that Doctor.
1. Disinhibition
The First Doctor physically appears to be physically very old, emotionally very grumpy, and behaviorally not shy about telling people how annoying they are.19 As we get older, an area at the front of our brains, the frontal lobes, starts to shrink,20 and so some of the important functions that the frontal lobes control (e.g., planning, judging, actively recalling21) start to fail—among them, our inhibitions. It could well be that the Doctor, toward the end of his first life cycle, is starting to show problems with his inhibition control (disinhibition) and so becomes rude and unhelpful.
2. Music
The Second Doctor, who has on occasion been described as a clown and can come across as disorganized and bumbling, shows a love of music that sets him apart from other regenerations. In fact, he is often found playing his trusty recorder while trying to concentrate and in times of danger.22 Psychologists have found that learning to play music can lead to enhancements in certain mental abilities, such as spatial reasoning23 (ability to mentally navigate and visualize objects three-dimensionally from different angles24). Even people who do not play an instrument can benefit from listening to music. Research suggests that as little as ten minutes of exposure to Mozart may improve people’s reasoning ability.25 This improvement is thought to occur because the musical and spatial processing areas overlap in the brain, and the music therefore primes areas needed for spatial reasoning. Psychologists who have not replicated these findings suggest that any increases in cognition are due to the music increasing arousal levels, thereby making people more likely to pay attention.26 Whatever the reason, music does have a positive effect on the brain, and the Doctor’s mental abilities are likely to benefit from playing and listening to music during this incarnation.
Made to regenerate by the Time Lords and then exiled on Earth, the Third Doctor has a much reduced ability to travel in time and space. Trapped on Earth in the twentieth century, he is inventive to make the most of the rather primitive technology he has available.27 This incarnation of the Doctor does enjoy using the available resources to create new devices such as the Whomobile. Is it possible that great inventors have a different type of brain? That could be the case. Researchers have found that when we generate a new idea, there is activation in various areas of the brain, including the left inferior frontal gyrus, anterior cingulate cortex, and precentral gyrus.28 The inventive Third Doctor may have enhanced functioning in these areas of the brain.
4. Generosity
The Fourth Doctor is outgoing and friendly, with an infectious sense of humor. He is generous, especially with his jelly babies. But what makes a person generous? Some researchers think that differences in hormone levels affect how generous people are. In one study, participants were asked to split a sum of money with a stranger. The researchers found that those who were given a dose of oxytocin, the so-called cuddle hormone, were 80 percent more generous than those who were given a placebo.29 Other hormones, such as testosterone, have been found to reduce generosity.30
5. Mental Toughness
The Fifth Doctor enjoys playing cricket.31 People who have a high degree of mental toughness (a resilient attitude, self- belief, and personal motivation) tend to make good cricketers.32 We know little about the brain structure or neurochemistry of someone who has higher levels of mental toughness. Some studies have suggested a genetic component. Others indicate that the neurotransmitter serotonin, known to modify our responses to stress, may be involved.33
6. Instability
Immediately after the Doctor’s regeneration into his sixth incarnation, it is clear that things have not gone well. Mentally the Doctor is unstable in that he appears impulsive, irritable, bad-tempered, and aggressive. These changes occur because the Doctor is experiencing poor inhibition control (disinhibition), suggesting that the areas that regulate self-control over our actions, the prefrontal lobes, are in some way not working correctly.34 As well as aggression, damage to the prefrontal lobes can increase extraversion, which may explain this Doctor’s outlandish style with his multicolored coat and bright yellow trousers.35
7. Eccentricity
The Seventh Doctor’s new personality is eccentric, to say the least. Eccentric behavior can have a genetic component. People who have relatives who suffer from schizophrenia have often been found to have mild characteristics of schizotypal personality disorders, a condition defined by pervasive eccentricity.36 These eccentric behaviors could be the result of a lack of dopamine in the prefrontal lobes or occur because people with schizotypal personality traits have a smaller left temporal lobe.37 Therefore, it is possible that this incarnation of the Doctor has a smaller left temporal lobe or less dopamine than previous regenerations.
8. Memory Loss
The Doctor regenerates into his eighth incarnation when Dr. Grace Holloway performs ill-advised heart surgery.38 Unfortunately for him, the anesthetic nearly stops his regeneration, and he is left suffering temporarily from a form of amnesia known as transient global amnesia, suddenly, though temporarily, forgetting everything about himself.39 This form of amnesia is not caused by extensive neurological damage to the brain but by migraine or seizures or maybe, in this case, the regeneration process.
8½. Combat Readiness
Little is known about the War Doctor other than that the Sisterhood of Karn gives the Eighth Doctor the ability to control his regeneration so that he can become this warrior.40 His brain is likely to be designed to overcome the problems people face in war zones, such as mental fatigue. We know that people in combat situations can make errors when they are under strain. A lack of food, water, and sleep can impair cognitive functioning. For example, when a person is dehydrated, the brain actually shrinks and so is unable to carry out complex thoughts.41
Although in today’s world we are not able to redesign brains to make better soldiers, there are drugs available that can help with mental fatigue. Central nervous system stimulants such as amphetamines can be used to keep pilots awake during long missions, or modafinil, a drug used for sleep disorders, can help keep the brain in a more wakeful state.42 Another thing that the Doctor could do to increase his resilience to war is to reduce his level of fear. Some researchers believe that the level of fear that we experience is driven by our genes.43 Maybe the Doctor in this regeneration has reduced the number of his genes that are associated with fear reactions.
Shortly after meeting the Doctor, Rose asks, “If you are an alien, how come you sound like you’re from the North?” The Doctor replies, “Lots of planets have a North!”44 It appears that after his regeneration, he has had a marked change in his accent. Children’s accents can change if they move to a new regional area, but for most of us, by the time we hit adulthood, our accents are fixed. However, very occasionally, people have been known to develop a new accent overnight, normally as a result of a brain injury, such as a stroke. This condition is known as foreign accent syndrome, in which a brain trauma can lead to a sudden alteration in a person’s speech rhythm and prosody. A young Englishman who suffered a stroke suddenly developed a Caribbean accent (specifically similar to the accent found on St. Lucia). In this case, the foreign accent disappeared after seventy-two hours.45 It could well be that the changes in the Doctor’s brain structure during regeneration affect his accent.
10. Neurorehabilitation
Newly regenerated, the Tenth Doctor challenges the leader of the Sycorax to a duel during which the Doctor’s hand is chopped off. The Doctor is able to grow another hand as he is within fifteen hours of his regeneration.46 Unlike humans who have to learn how to use new limbs, the Doctor appears not to need any form of neurorehabilitation and can start to use his new hand immediately. Even humans can learn to adopt a hand that is not their own, but they require a period of adjustment during which they must adapt to using their new limbs. In the rubber hand illusion, a researcher strokes both the participant’s real hand (which is hidden) and the rubber hand, which the participant can see. Over time the participant starts to perceive the rubber hand as his or her real hand.47
When the Doctor turns into “a madman with a box”48 in his eleventh regeneration, he becomes youthful, lively, and impatient, getting quickly bored and bouncing continually from one task to the next.49 The impulsivity and hyperactivity he exhibits suggest that he has some traits of attention-deficit hyperactivity disorder (ADHD). Indeed, this regeneration of the Doctor can be quite childish. Children with ADHD can take a few years longer than others to mature into adulthood. Although the precise reason why ADHD occurs in humans is not known, it is thought that there could be differences in the neurotransmitter dopamine, a nervous system chemical that performs a variety of cognitive, emotional, and motor functions.50 This Doctor benefits from the high levels of energy that his hyperactive traits give him.
12. Autism Spectrum
The Twelfth Doctor appears to have unconsciously given himself the face of a man he previously saved in Pompeii to remind himself to show compassion.51 Whether despite that reminder or because of it, this Doctor appears to have problems with empathy and with understanding complex emotions. In fact, Clara writes a number of cards for him to help him give the right emotional response.52 This regeneration could give him some of the traits of the neurodevelopmental condition Asperger’s syndrome. Although the Doctor appears to have learned some compensatory strategies, he does appear to have a less than complete understanding of the social world compared to other Doctors. Psychologists have found that scientists (including mathematicians) are more likely to have Asperger’s or high-functioning autism compared with academics who are not scientists.53 In Asperger’s, it is thought that there are abnormalities in the brain’s white matter and this leads to differences in the way in which different areas of the brain talk to each other.54
Beyond Brains and Behavior
Neuropsychology is a relatively young area of psychology, and advances in techniques such as brain imaging are likely to lead to further advances in this field. It is clear from our current understanding of how the human brain works that the Doctor’s shares some similarities with ours but in other ways is very alien. One of the most striking differences between the Doctor and humans is his ability to regenerate. Although similar to the process of synaptic pruning in adolescence, regeneration is much more violent and traumatic, leading to exaggerated adolescentlike behaviors in the Doctor. Errors in the regeneration process as well as changes in brain structure as a result of regeneration lead to each Doctor having a markedly different personality in each regeneration. Our understanding of the human brain allows us to guess about the neuropsychological underpinnings of the Doctor’s behavior, but neuropsychological techniques must improve before brain and behavior can be more richly explained.
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1. Christmas special, “The Time of the Doctor” (December 25, 2013).
2. Maslow (1943), p. 382.
3. Classic serial 10–1, The Three Doctors (December 30, 1972—January 20, 1973); anniversary special, The Five Doctors (November 25, 1983); modern episode 1–11, “Boom Town” (June 4, 2005).
4. Witelson et al. (1999).
5. Beyerstein (1999); Blackburn (2014); Boyd (2008); Radford (1999).
6. Lyons et al. (2014); White et al (1973).
7. Penfield (1968).
8. Buxton (2002); Huettal et al. (2009).
9. DeWitt & Rauschecker (2013); Dronkers et al. (2000); Poeppel et al. (2008).
10. Classic serial 13–5, The Brain of Morbius (January 3–January 24, 1976).
11. Classic serial 11–5, Planet of the Spiders (May 4–June 8, 1974).
12. Classic serial 4–3, The Power of the Daleks (November 5–December 10, 1966); 7–1, Spearhead from Space (January 3–24, 1970); 12–1, Robot (December 28, 1974–January 18, 1975); 19–1, Castrovalva January 4–13, 1982); 21–7, The Twin Dilemma (March 22–30, 1984); 24–1, Time and the Rani (September 7–28, 1987); Doctor Who (1996 television movie); Christmas special, The Christmas Invasion (December 25, 2005); modern episode 5–1, “The Eleventh Hour” (April 3, 2010); 8–1, “Deep Breath” (August 23, 2014).
13. Blakemore & Choudhury (2006); Chechik et al (1999).
14. Anniversary special “The Day of the Doctor” (November 23, 2013).
15. McGlashan & Hoffman (2000).
16. Classic serial 21–7, The Twin Dilemma (March 22–March 30, 1984).
17. Maguire et al. (2006).
18. Friston (2002).
19. Classic serial 1–1, An Unearthly Child (November 23–December 14, 1963).
20. Von Hippel et al. (2008).
21. Goldberg (2002).
22. Classic serial 10–1, The Three Doctors (December 30, 1972–January 20, 1973).
23. Rauscher et al. (1993).
24. Gardner (2006).
25. Rauscher et al. (1993
26. Thompson et al. (2001).
27. Classic serial 7–1, Spearhead from Space (January 3–24, 1970); 10–1, The Three Doctors (December 30, 1972–January 20, 1973).
28. Beaty et al. (2014).
29. Zak et al. (2007).
30. Zak et al. (2009).
31. Classic serials 19–1, Castrovalva (January 4–January 12, 1982); 19–5, Black Orchid (March 1–March 2, 1982).
32. Weissensteiner et al. (2012).
33. Sheard (2012).
34. Brower & Price (2001).
35. Grafman et al. (1996).
36. American Psychiatric Association (2013).
37. Rosell et al. (2014).
38. Doctor Who (1996 television movie).
39. Romero et al (2013).
40. Minisode, The Night of the Doctor (November 14, 2005).
41. Lieberman et al. (2005).
42. Stickgold & Walker (2010).
43. Moreno (2006).
44. Modern episode 1–1, “Rose” (March 26, 2005).
45. Roque et al. (2012).
46. Christmas special, “The Christmas Invasion,” (December 25, 2005.
47. Botvinick & Cohen (1998).
48. Modern episode 5–1, “The Eleventh Hour” (April 3, 2010).
49. Modern episode 5–10, “Vincent and the Doctor” (June 5, 2010).
50. Barkley (2014).
51. Modern episode 9–5, “The Girl Who Died” (October 17, 2015).
52. Modern episode 9–3, “Under The Lake” (October 3, 2015).
53. Baron-Cohen et al. (2001).
54. Van Duin et al. (2014).