The tumour that made a murderer
By all accounts, Charles Joseph Whitman was, for much of his short life, a model citizen. He was a polite, intelligent youth; he was an Eagle Scout; he married his childhood sweetheart at age 17; he joined the Marine Corps and became a sharpshooter. Then, after leaving the service, he became an architectural engineering student at the University of Texas at Austin.
But then, on the night of 31 July 1966, he stabbed his wife and his mother to death; and, the next day, packed a bag full of guns and climbed the main tower building of the university. On his way up the tower he killed three people. Once at the top, he used a high-powered rifle to kill another 10 people, and wound 33. One of the injured was a heavily pregnant young woman, shot through the stomach, killing the unborn child. Whitman then shot her fiancé dead as she lay wounded. Eventually police managed to reach him and kill him.
You've probably heard plenty of stories like this, and Whitman does fit the profile of a spree killer: a young, white, male gun-owner. But what distinguished him was that, the night he murdered his wife and mother, he wrote a note. That note said:
I don't really understand myself these days. I am supposed to be an average reasonable and intelligent young man. However, lately (I can't recall when it started) I have been a victim of many unusual and irrational thoughts.
It was after much thought that I decided to kill my wife, Kathy, tonight … I love her dearly, and she has been as fine a wife to me as any man could ever hope to have. I cannot rationaly [sic] pinpoint any specific reason for doing this.
Whitman requested that his body be subjected to a post-mortem examination, because he had been suffering for months with terrible headaches and strange violent urges, and he thought something had changed in his brain:
I talked with a Doctor once for about two hours and tried to convey to him my fears that I felt come [sic] overwhelming violent impulses. After one visit, I never saw the Doctor again, and since then have been fighting my mental turmoil alone, and seemingly to no avail.
He seems to have been right. As David Eagleman recounts in his book Incognito: The Secret Lives of the Brain, the post-mortem was carried out, and a tumour the size of a 10p coin was found in his brain. The tumour was in a part of the brain called the thalamus, and pressed against another part, the amygdala, which is involved in regulating our fear and anger responses. We will never know for sure what caused him to snap, but the rational, thinking part of Whitman's mind appears to have been overwhelmed by a little lump of tissue which pushed him to kill.
The woman who couldn't recognise her own reflection
Humans are incredibly good at seeing faces. So good, in fact, that we seem them almost everywhere. We see Jesus in burnt toast and smiley faces in punctuation. :-) Faces leap out at us, and we struggle to look away. Eye-tracking studies show that even newborn babies will choose to look at faces and facelike things over other patterns. Our brains don't see faces like they see the rest of the world. We have what appears to be a dedicated mechanism for spotting, recognising, and remembering individual faces.
But sometimes, when a part of the brain called the fusiform gyrus, towards the bottom of your skull, is damaged – in a stroke, for example – it removes this mechanism. People become almost completely incapable of telling one face from another. It is far worse than the normal "I'm terrible at remembering faces", and can have serious social consequences. One sufferer, in an interview with New Scientist, said she mistook other men for her partner, or walked past men she'd been on dates with the previous night. And, she said, she often doesn't recognise the woman she sees in the mirror. Another sufferer said that watching films is a joyless chore for him, because he spends the whole time trying to work out which character is which. "I had assumed Ocean's 11 was designed to be a movie where you're not supposed to be able to keep track of the characters," he wrote.
Sufferers tend to create workarounds – so they will recognise people from their gait, or from their clothes or hair, or the context they meet them in. When those things change it can be thoroughly confusing.
About 2.5% of people are believed to suffer from prosopagnosia, but many are unaware of it, because they have never experienced any other way of life: Oliver Sacks, the author of The Man Who Mistook His Wife for a Hat, is one sufferer. If you think you may suffer from it, you can take a test on the Faceblind prosopagnosia research centre website.
The woman who thought her husband was an impostor
In 1923, a pair of French doctors, Joseph Capgras and Jean Reboul-Lachaux, described a very strange patient. Madame M reported that her husband had been replaced by an impostor. Not only her husband, in fact, but her family, her friends and her neighbours. Unlike prosopagnosia sufferers, Madame M was quite capable of recognising all of their faces. But she didn't believe that they were the "real" them.
Many more cases of the syndrome, subsequently named after Capgras, have been described since then. One, Mrs D, refused to sleep in the same bed as her "impostor" husband and locked her bedroom door against him, asking her son to bring her a gun.
The condition is frequently linked to mental illnesses such as schizophrenia, and to specific brain damage. The neuroscientist Vilayanur Ramachandran, author of The Tell-Tale Brain: A Neuroscientist's Quest for What Makes Us Human, believes that the problem is caused by a failure of two brain systems to link up. There's the fusiform gyrus – the bit that goes wrong in prosopagnosia – which allows us to recognise faces. And then there's another bit of our brain, the limbic system and amygdala, which deals with our emotional response to that person. Seeing a person you love, such as your husband or mother, should provoke an emotional response. But if the link between the face-recognition bit and the emotional-response bit is broken, seeing your mother might not provoke an emotional response.
Ramachandran hypothesises that this broken link is what causes Capgras. "When [a Capgras patient] looks at his mother … even though he realises that she resembles his mother, he does not experience the appropriate warmth, and therefore says 'well, if this is my mother, why is it I'm not experiencing any emotion? This must be some strange person.'"
The man who thought he was dead
A Japanese patient in 2012 reported a very worrying symptom: He told doctors he was dead. "I guess I am dead," he said. "I'd like to ask for your opinion." Since dead people are usually unable to tell people about it, the doctors looked into other possible diagnoses, and found that he had suffered an infarction, a kind of stroke, in the right hemisphere of his brain.
This delusion has been recorded several times, although it is not straightforwardly "believing you are dead". In many patients, it manifests as a belief that parts of their body have disappeared, or other "nihilistic delusions concerning the body". The first appears to have been in 1788, when Charles Bonnet, a Swiss philosopher, reported that an elderly woman had declared herself to be dead and insisted her family mourn her. Eventually they gave in, and pretended to do so, while she complained about the colour of her shroud.
A century or so later, a French neurologist, Jules Cotard, recorded the case of a woman who believed herself to have no internal organs, and also to be immortal. The condition was named after him: Cotard's syndrome, or Cotard's delusion. Other sufferers have claimed that they don't have any blood, or that they haven't gone to the toilet in years. One 88-year-old man "was convinced he was dead and felt very anxious because he was not yet buried". Another patient was "convinced her brain had vanished, her intestines had disappeared, and her whole body was translucent. She refused to take a bath or shower because she was afraid of being soluble and disappearing through the water drain."
Like Capgras syndrome, Cotard seems to be a problem of emotional responses becoming detached from perceptions, and seems to be linked to damage to the fusiform gyrus and amygdala. But instead of the patient losing the sense of familiarity when they see family members, they don't get that sense when they look at themselves, or at parts of themselves.
The tumour that made a family man a paedophile
In 2000, a man in America started behaving very differently. A previously happily married man, a schoolteacher and stepfather, after he turned 40 he began visiting prostitutes and uncontrollably collecting child pornography. Then, worst of all, he made sexual advances to his prepubescent stepdaughter. His wife had him evicted from his home, and he was convicted of child molestation and sentenced to a course of rehabilitation. On that course, he made more sexual advances, towards other clients and towards staff, and was sent to prison.
Before he was imprisoned, though, he complained of increasingly bad headaches and worse urges – it was reported that he feared he would rape his landlady – and took himself to hospital. Doctors found an egg-sized tumour in a brain region known as the orbifrontal cortex, which is linked to impulse control, judgment, and social interaction. They removed the tumour, and all of the inappropriate sexual urges disappeared. Some months later he moved back into his home, with his wife.
A year later, he again reported headaches, and again displaying paedophilic behaviour. A scan revealed that a part of the tumour had been missed, and it was growing back. When surgeons removed it again, the urges went away again. Russell Swerdlow, one of the neurologists on his case, said that the man was aware that his actions were wrong, but that "in his words, the 'pleasure principle' overrode his restraint". "We're dealing with the neurology of morality here," he went on.
Damage to the frontal lobes often reduces our ability to restrain our impulses and urges. David Eagleman uses examples like this to point out that the notion of "responsibility" is a slippery one: Is the man above "responsible" for his actions? Is a patient with frontotemporal dementia? Since we are our brains, what happens to "us" when our brain changes? Should the law be changed to reflect current neuroscientific thinking?
The man who could only say one syllable
When Louis Victor Leborgne died in 1861, aged 51, he had been virtually speechless for 21 years. Not completely speechless: He could speak one word, "tan". Over and over again: "Tan. Tan." In the months before he died, a doctor called Pierre Paul Broca, a language specialist, had become interested in his case. Leborgne was apparently still intelligent, still aware of his surroundings, still capable of telling where he was and how long he'd been there. But he'd lost all use of language, reported Broca:
He could no longer produce but a single syllable, which he usually repeated twice in succession; regardless of the question asked him, he always responded: tan, tan, combined with varied expressive gestures. This is why, throughout the hospital, he is known only by the name Tan.
After Leborgne's death, Broca examined his body, and found a lesion in the posterior inferior frontal gyrus – a brain region now known as "Broca's area".
Later research has shown that it's a bit more complicated than simply "Broca's area is the language centre". Lots of the surrounding regions are involved in language production. But Broca was among the first to realise that language is localised in the brain. His research also represents one of the first demonstrations that our minds aren't all-purpose intelligences, but are apparently made of lots of separate parts with highly specific tasks.
People who are blind but say they're not, and people who aren't blind but think they are
Sufferers of Anton–Babinski syndrome are blind. The vision centres of their brain are damaged: They cannot see. But they don't realise that. Patients will deny it if asked, and if not asked, will behave as though they are sighted. In his book The Divine Banquet of the Brain, the neurologist Macdonald Critchley describes how patients' delusions end up being revealed:
Attention is aroused however when the patient is found to collide with pieces of furniture, to fall over objects, and to experience difficulty in finding his way around. He may try to walk through a wall or through a closed door on his way from one room to another. Suspicion is still further alerted when he begins to describe people and objects around him which, as a matter of fact, are not there at all.
The disorder is the result of damage to the occipital lobe. It has a perfect opposite in the shape of "blindsight", which is the result of damage to the striate cortex. Patients who suffer from blindsight will claim to be entirely blind (usually on one side of their visual field), and will deny being able to see the objects in front of them, but when forced to guess what the object is, will tend to get it right.