The Tell-Tale Brain: A Neuroscientist's Quest for What Makes Us Human

by V.S. Ramachandran

Picasso’s Cubist pictures were anything but realistic. His women—with two eyes on one side of the face, hunchbacks, misplaced limbs, and so on—were considerably more distorted than any Chola bronze or Mogul miniature. Yet the Western response to Picasso was that he was a genius who liberated us from the tyranny of

realism by showing us that art doesn’t have to even try to be realistic. I do not mean to detract from Picasso’s brilliance, but he was doing what Indian artists had done a millennium earlier. Even his trick of depicting multiple views of an object in a single plane was used by Mogul artists. (I might add that I am not a great fan of Picasso’s art.)

Is there a logical reason for grouping colors? Is it just marketing and hype, or is this telling you something fundamental about the brain? This is the “why” question. The answer is that grouping evolved, to a surprisingly large extent, to defeat camouflage and to detect objects in cluttered scenes. This seems counterintuitive because

when you look around, objects are clearly visible—certainly not camouflaged.

Or that absurd but tenaciously popular factoid about how people only use 10 percent of their brains—whatever that’s supposed to mean. (When reporters ask me about the validity of this claim, I usually tell them, “Well, that’s certainly true here in California.”)

I now realize that my drawing illustrates one of the most important laws in aesthetic perception: the abhorrence of coincidences. Imagine that Figure 8.2a depicts a real visual scene. Look carefully and you’ll realize that in real life, you could only see the scene in Figure 8.2a from one vantage point, whereas you could see the one in Figure 8.2b from any number of vantage points. One viewpoint is unique and one is generic. As a class, images like the one in

are much more common. So Figure 8.2a is—to use a phrase introduced by

Horace Barlow—“a suspicious coincidence.” And your brain always tries to find a plausible alternate, generic interpretation to avoid the coincidence. In this case it doe...

The notion that many aspects of the human psyche might arise from a push-pull antagonism between complementary regions of the two hemispheres might seem like a gross oversimplification; indeed, the theory itself might be the result of “dichotomania,” the brain’s tendency to simplify the world by dividing things into polarized opposites (night and day, yin and yang, male and female,

and so on). But it makes perfect sense from a systems engineering point of view. Control mechanisms that stabilize a system and help avoid oscillations are the rule rather than the exception in biology.

anosognosia.

FREGOLI SYNDROME: DOCTOR, EVERYONE LOOKS LIKE AUNT CINDY

Cotard syndrome.

On the one hand, less extreme forms of depersonalization—in which the patient feels like an “empty shell” but, unlike a Cotard patient, retains insight into his illness—can occur in the complete absence of depression.

The explanation I propose is to think of Cotard syndrome as an extreme and more general form of Capgras syndrome. People with Cotard syndrome often lose interest in viewing art and listening to music, presumably because such stimuli also fail to evoke emotions.

DOCTOR, IAMONE WITH GOD

temporal lobe epilepsy (TLE).