There are as many bodies packed into this 40th floor auditorium as there are lit up windows in the surrounding skyscrapers. Here in 7 World Trade Center, peering into Ground Zero and glowing amidst a thrum of office buildings downtown, we are gathered for a talk organized by the New York Academy of Sciences. Neurologist V.S.Ramachandran will speak about the human brain via a number of patients and case studies he presents to us as stories, slides and snide asides. But first, a word—or several—about Ramachandran. The smiling emcee quotes reviewers of Ramachandran’s latest book, THE TELL-TALE BRAIN (“neuroscientist’s quest for what makes us human”), who lavish titles upon its stubbornly curious author such as: “the latter day Marco Polo journeying the Silk Road of Science,” the “modern Broca” and “the Galileo of cognition.” The 2007 Padma Bhushan recipient leaps onto the stage—gangly, curly hair, bright eyes. He starts with a basic introduction—how else can one begin to understand the brain?—cupping his hands together: “the brain is a three pound mass of jelly, flesh you can hold in your hand. It contemplates vast space, God…it contemplates itself contemplating. This is an organ of staggering complexity.” I’m only mildly distracted by his accent, an Indian-American hybrid with the occasional ‘r’ rolled long enough to expose his South Indian roots (holla). He maintains eye contact with the crowd and cracks sudden smiles at the audience when explaining particularly unexpected outcomes. His subject matter and presentation technique make him irresistible to listen to.
How do we understand such a rich organ, Ramachandran asks. There are three ways:
1) Brain imaging. Ramachandran alludes to the “brain imaging mania going around,” likening it to “giving an eight year old a knife and having him cut into everything!” But such an approach isn’t all bad, some accidents do lead to discovery.
2) Recording brain signals. It’s like eavesdropping on the activity of brain cells, Ramachandran says, and a different way to understand brain behavior.
3) “Structure function correlations.” Patients with brain lesions produce a highly selective loss of functionality, he explains, allowing for very specific and very revealing experiments. What is surprising and interesting about these syndromes—say, not being able to recognize a person by face, but instead by voice or gait—is a “lovely example of what we call neuroscience,” he gushes.
Ramachandran and his colleagues get to “play detective on these patients” in paradoxically elementary ways, using games and pokes to understand the brain’s nonstop electric activity. He mentions the tension between neurologists who study hundreds of patients and their data, and his own approach: astute observation on a few patients. Either way, “nine out of ten studies are a waste of time;” it’s with the 10th study that you “hit the jackpot.” Ramachandran stares at us for a moment. “I’m telling you only the success stories, obviously,” given his one-hour time slot. He pauses again. “By the way, am I going too fast?”
Cabgras Syndrome
Ramachandran’s focus is the third technique of brain study he described: understanding lesions in the brain that interrupt otherwise normal behavior, showing how the brain typically functions, how it adapts when something is amiss, and how human behavior is affected as a result. His first story is about a patient, one of his students, who has been in a car accident and injured his head. When he wakes from his coma, he seems fine, showing self-awareness, communicating clearly and playing chess with his professor. But, he insists that the woman standing in his hospital room who looks exactly like his mother is not her but an imposter, even though she is very much his mother.
The background, some argue, is Freudian: the Oedipal argument that seeing a woman who resembles your mother but also generates sexual arousal in you cannot be your mother. The part of the cortex that controls sexual attraction is damaged in this patient’s case, hence the peculiar reaction. “Thank God” for the cortex, Ramachandran says, “otherwise you’d be sexually aroused by your mother.”
“Now, this is a very ingenious explanation, as all Freudian theories are, as you New Yorkers well know,” he continues. But can it be taken seriously? What about when patients are unable to recognize their pets? Do we have to invoke ideas of “latent bestiality?” Ramachandran emphatically discards the Freudian theory, advocating his own. It features the Fusiform Gyrus, which recognizes objects, and the Amygdala, which fills in emotional significance—is the object a predator, prey, mate or boss?—so that you can understand who/what you are interacting with. When you are nervous and start sweating, for example, your body is anticipating muscular exertion from fleeing or pursuing the entity before you. So if the Fusiform Gyrus and Amygdala are no longer connected, what happens? You see a person standing in front of you—say, your mother—but there is no physical reaction—that is, skin temperature doesn’t go up, you don’t start sweating—nor is there an emotional one. Everyone sweats when they see their mother, Ramachandran reminds us; “you don’t have to be Jewish!” so such a lack of reaction leads you to conclude that the person standing in front of you cannot be your mother.
When testing patients with a normal Fusiform Gyrus for physical responses to people, neurologists have seen consistent results:
- Strangers – no galvanic response
- Lion – huge jolt in electrical activity
- Mother – start sweating!
Ramachandran’s student has no trouble recognizing his mother on the phone. The connection between his Auditory Cortex and Amygala is intact, so he can recognize her voice on the phone and respond with the expected, appropriate physical and emotional reaction. The Fusiform Gyrus is specific to visual recognition, so when confronted visually, the patient’s delusion kicks in: that woman is not my mother.
Phantom Limbs
Not all amputations are injury or disease-driven. Ramachandran describes patients who demand to have a limb removed. Other than their desire to have an arm amputated, he insists, “ they’re perfectly normal,” and I wonder what ‘normal’ means to someone who studies the brain! Why would someone ask to have something taken away from their body? Could there be a Freudian explanation, where the patient is looking for attention? What about the Freudian idea that the stump remaining resembles a huge penis “This is bullshit,” he declares, and seeing our raised eyebrows, clarifies that “I’m not making these up!”
Phantom limbs extend from arms and legs to internal organs like the uterus, even menstrual cramps. What’s the Freudian explanation now, Ramachandran challenges the audience. “Again, all of you know, that’s nonsense.”
Ramachandran closes his eyes, demonstrating how his brain can construct an image of where he is—self awareness—and what he looks like—body image—without explicit visual feedback. But what happens if, eyes open or closed, you perceive a natural part of your body as unnatural? He explains that if the brain doesn’t receive signals from a part of the body, it can seem intrusive to the person. Such a discrepancy in neuro-signal reception can make a part of the body seem “too much a part of me,” as one patient complains. Take the left arm as an example: brain signals above the elbow are normal, but below the elbow are missing, so the patient reacts adversely to his lower arm. It makes sense that he wants it removed.
Clicking to the next slide in his presentation, Ramachandran shows us a man’s face with a map drawn on his cheek. It is a complete mapping of an amputated left hand that the brain now perceives on this patient’s cheek. Ramachandran pauses. “Actually there are several maps [mapping brain and body signals] but I’ll pretend there’s only one for this lecture.” He explains that the hand area of the brain is hungry for stimulation and totally deprived, since the hand has been amputated, so the face region of the brain, adjacent to the hand region, becomes over-stimulated. Signals cross over from the hand to the face region of the brain, and when the patient with an amputated left hand is touched on the cheek, he feels sensation in his phantom left hand.
“It’s kinda fun to do these things,” Ramachandran admits when describing how he touched his patient’s cheek with ice cubes. The cold water trickled down the patient’s cheek, which the patient felt as water trickling down his arm. When Ramachandran had his patient lift his arm up, and then touched his cheek with an ice cube, the patient felt the trickle of water down his cheek as a gravity-defying trickle up his amputated arm. This is how sophisticated the mapping of the brain is, Ramachandran announces triumphantly.
His next story is about a patient with an amputated foot. He shows us the mapping of body parts in the brain and we can see that the region receiving sensations from genitals is neighbors with the region receiving sensations from the foot. “Makes you wonder about foot fetishes,” and tap dancing, Ramachandran quips. The patient had described to Ramachandran how sex felt:
His orgasm is “now much bigger than it used to be,” Ramachandran shared with another neurologist.
“It’s all in his head,” the neurologist scoffed to Ramachandran.
“Of course it is!” Ramachandran rejoined with a totally straight face.
“Phantom paralysis,” when a phantom limb is paralyzed, sounds like an oxymoron, but isn’t. First we must understand what “learned paralysis” is: the visual feedback when signals are sent from the Cerebellum to an unresponsive arm that informs the patient that his arm is paralyzed. This persists once the arm has been amputated, so when a paralyzed arm is amputated, the phantom arm feels paralyzed too.
How can we address this problem? Create a virtual reality to access phantom limbs? For $2 million? “Forget that,” Ramachandran told himself when he was first investigating the problem; surely there was a smarter and cheaper solution. “Then we hit on the idea of using a $2 mirror.”
A mirror plays the critical role of providing visual feedback during neuro-rehabilitation. A patient missing his left arm can “see” it by placing his arm in Ramachandran’s mirror box creation, that reflects his right arm 180 degrees and positions it, in the mirror box, where his left arm would be. A patient can experience his phantom limb moving (out of an uncomfortable position) by moving his intact arm inside the mirror box. Brilliant in its simplicity but Ramachandran prefers to joke: moving a phantom arm is, “if you think about it, a completely useless skill.”
Not so useless for one patient who took the mirror box home to exercise his phantom arm with. He called Ramachandran two weeks later, happy to announce that his phantom arm, until now in excruciating pain, had disappeared! The qualifier? His phantom fingers had relocated to his shoulder! “Can you redesign the mirror box to reach that height?” the patient asked Ramachandran.
The mirror box can ease the pain the phantom limbs experience, reduce their inflammation and regulate skin temperature overall, by providing feedback to the brain that the phantom limb is neither intrusive nor unreal. Swollen phantom limb? Equip the mirror box with appropriate lenses so make the body part look smaller, and the phantom limb’s swelling “reduces.” The phantom limb is a “curious disorder,” Ramachandran says, his voice rising and falling like he is narrating a story about a wild animal with that respectful tone of wonder and wisdom. That the brain can be taught to unlearn the pain is a “completely zany idea!” He cautions us about the heavy press mirror neurons have received recently, but reminds us, sardonically, that such “media hype doesn’t mean it’s not important!” Glancing at the podium, Ramachandran addresses us with an aside. “By the way, is this count down or count up? Oh, count down. Looks good, I still have another 18 minutes—” and he jumps back into his lecture. It takes me a moment to realize he’s looking at a clock on the podium, the only thing in the room more informed than him this evening!
We discuss a fundamental human trait, empathy, and learn about its corresponding empathy neurons: seeing someone else do something, such as touch a hot plate, causes your neurons fire and allows you to imagine the sensation of the hot plate, while, simultaneously, your own body sends null signals to the brain indicating that you are in fact NOT touching anything hot, so what you are seeing happen to someone else is NOT your reality. One set of neurons partially veto another, so we experience empathy instead of projection. This becomes tricky for people with phantom limbs, where absent body parts cannot produce null signals, and the brain cannot distinguish his own experiences from another person’s as clearly.
“I’m not saying mirror neurons --> culture --> civilization!” but Ramachandran believes that empathetic behavior by the brain is vital to emotional development and human interaction.
Describing what he has dubbed “Gandhi neurons” that dissolve the barrier between “your consciousness and mine,” he warns that it “smacks of Eastern mysticism.”
He glances at the clock. “Ok, next topic.”
Synesthesia
Ramachandran opens with a conclusion: Synesthesia is genetic, and also 8 times more common in artists, poets and novelists. He shares the proposed causes of synesthesia:
1) Synesthetes are crazy. Ramachandran rejects this categorically: “that’s not a theory.” In neuroscience, he says, if a patient sounds crazy, it’s because the neurologist isn’t smart enough to figure out what the problem is.
2) Synesthetes did lots of acid and smoked lots of pot. Ramachandran allows for this theory to make more sense at Berkeley than UCSD, but so what? Synesthesia is not a consistent outcome, so the correlation is not up to snuff.
3) Synesthetes played with the same fridge magnets as kids, he jokes. But that isn’t consistent with the disorder being genetic!
4) In that case, is synesthesia just a metaphorical view of the world? Ramachandran shrugs: “what the hell is a metaphor?”
Ramachandran shows us how a synesthete would look at an arrangement of numbers identifying patterns that we take longer to see (the triangle of 2’s in this diagram). “If they’re crazy,” he wonders, “how can they be better [at this brain exercise] than us?”
His theory is that there is accidental cross-wiring between the number and color areas of the brain, which are adjacent to each other. When he shows a patient a color, the number area of the patient’s brain lights up instead. In a fetus there are tremendous redundancies of connections in the brain which are pruned away by pruning genes. But what happens if these genes are defective?
Shakespeare said, ‘It is the East and Juliet is the sun.’ Ramachandran points out that Shakespeare didn’t say ‘yellow ball of fire.’ (“Schizophrenics would say that, but that’s another story.”) We say that cheddar cheese tastes sharp—“what?!”—and people understand that that means. So returning to the theory that novelists, artists and poets are more likely to be synesthetes, it becomes clear that they are more likely to use metaphor, and therefore more likely to be novelists, artists and poets!
“I have 3 minutes left but I don’t know what to talk about,” Ramachandran says, glancing as his clock once again. He closes with the reminder that neuroscientists can begin to make progress by asking the right questions, correlating psychophysics, phenomenology and more, to continue to explore and understand the brain, that most complex of human organs.