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Can the Brain Explain Your Mind?

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Cyril Ruoso/JH Editorial/Minden Pictures/Getty Images
A satin bowerbird collecting blue legos to decorate his bower and attract a mate. Colin McGinn writes: ‘Peacocks, bees, and bowerbirds possess rudimentary aesthetic responses, [Ramachandran] suggests, and we are not so different.’

Ramachandran goes on to treat autism as a deficiency in the mirror neuron system: the difficulties of play and conversation, and the absence of empathy characteristic of autism derive, Ramachandran holds, from a failure of cerebral response to others. The autistic child cannot adopt the point of view of another person, and fails properly to grasp the self-other distinction, and that is what mirror neurons enable. Ramachandran claims confirmation of his theory in the lack of “mu-wave suppression.” In normal people the brainwave known as the mu wave undergoes suppression any time a person makes a voluntary movement or watches another perform the same movement, whereas in autistics, mu-wave suppression occurs only when performing actions, not when observing the action of others. The brain signature of empathy is thus absent in autistics. Autism accordingly results from an anatomically identifiable dysfunction—dead mirror neurons, in effect.

Ramachandran also postulates that the emotional peculiarities of autistics may be caused by disturbances to the link between the sensory cortices and the amygdala and limbic system, both centers involved in emotion. The normal pathways are blocked or modified in some way, so that the usual pattern of emotional response to stimuli is thrown off-kilter—trivial stimuli that human eyes register as uninteresting become affectively charged. Once again, anatomy rules, not psychology (so autism has nothing to do with bad parenting or Freudian struggles).

What can the structure of the brain tell us about language? In his treatment of this subject Ramachandran ranges over Broca’s area of the brain (responsible for syntax) and Wernicke’s area (semantics), various types of aphasia, the question of whether we are the only species with language, nature versus nurture, and the relationship between language and thought. Then Ramachandran squares up to the vexed problem of origins: How did language evolve? His solution is nothing if not bold: bouba-kiki supplies the magic solution. We need an account of how a lexicon got off the ground, and cross-modal abstraction is the answer. The bouba-kiki experiment

clearly shows that there is a built-in, nonarbitrary correspondence between the visual shape of an object and the sound (or at least, the kind of sound) that might be its “partner.” This preexisting bias may be hardwired. This bias may have been very small, but it may have been sufficient to get the process started.

In this view, words began by way of abstract similarities between visually perceived objects and intentionally produced sounds—we call things by sounds that are like what they name, abstractly speaking. Ramachandran introduces the word “synkinesia” to refer to abstract likenesses between types of movement—as, for example, between cutting with scissors and clenching the jaws. The suggestion, then, is that speech exploits not merely sight-sound similarities but also similarities between movements of the mouth and other bodily movements: the “come hither” hand gesture of curling the fingers toward you with palm up is said to be mirrored by the movements of the tongue as the word “hither” is uttered. This is not claimed to be the sole engine of language development, but it is said to provide an initial vital stage—how vocabulary began.

As to syntax, Ramachandran proposes that the use of tools afforded its initial foundation, particularly the use of “the subassembly technique in tool manufacture,” for example, affixing an ax head to a wooden handle. This composite physical structure is compared to the syntactic composition of a sentence. Thus tool use, bouba-kiki, synkinesia, and thinking all combine to make language possible—along with those ubiquitous mirror neurons. Just as fine-tuned hearing evolved from chewing in the reptilian jawbone structure (an “excaption” in the jargon of evolutionists)—as bones selected for biting became co-opted in the small bones of the ear—so human language grew from prelinguistic structures and capacities, building upon traits selected for other reasons. The jump to speech was therefore mediated, not abrupt.

Not content merely with explaining the origin of language, Ramachandran next ventures into the evolution of our aesthetic sense. He seeks a science of art. Enunciating nine “artistic universals,” he propounds what he allows is a “reductionist” view of art, attempting to provide brain-based laws of aesthetic response. Peacocks, bees, and bowerbirds possess rudimentary aesthetic responses, he suggests, and we are not so different. Thus we respond well to “grouping” and “peak shift”: we like similarly colored things to go together, and we are entranced by certain kinds of exaggeration of ordinary reality (as with caricatures) or other unrealistic images in art (like the Venus of Willendorf, as cited by Nigel Spivey in How Art Made the World). These biases result from our evolutionary ancestry as arboreal survivors—seeing lions through leaves and so on. Our taste for abstract art is compared to the propensity of gulls to be attracted to anything with a big red dot on it, since mother gulls have such a dot on their beak: “I suggest this is exactly what human art connoisseurs are doing when they look at or purchase abstract works of art; they are behaving exactly like the gull chicks.”

Throughout this cheerfully reductive discussion Ramachandran makes no real distinction between the arousal value of a stimulus and its strictly aesthetic value—he takes emotional power to be equivalent to aesthetic quality, at least at a primitive level. He eventually gets around to considering whether such a conflation is acceptable, making the brief remark: “It may turn out that these distinctions aren’t as watertight as they seem; who would deny that eros is a vital part of art? Or that an artist’s creative spirit often derives its sustenance from a muse?” In other words, he sees no important distinction between the aesthetic quality of a work of art and its attention-grabbing capacity—it’s all big red dots and enlarged buttocks (as in his discussion of sculptures of the Indian goddess Parvati), and the distinctions between, say, Titian and Picasso have no place.

Finally, we have an even more speculative chapter on the brain and self-consciousness. Again, we read of many strange syndromes: “telephone syndrome,” in which a man can only recognize his father when talking to him on the phone; “Cotard’s syndrome,” in which a person thinks that he or she is dead; obsessed individuals who want to have a healthy limb amputated (“apotemnophilia”); “Fregoli syndrome,” in which everyone looks like a single person; “alien-hand syndrome,” in which a person’s hand acts against his will. These curious cases are supposed to shed light on the unity of the self and self-awareness, even on consciousness itself. Ramachandran asserts that alien-hand syndrome “underscores the important role of the anterior cingulate in free will, transforming a philosophical problem into a neurological one.” The anterior cingulate, he observes, is a C-shaped ring of cortical tissue that “lights up” in many—almost too many—brain input studies.

What should we make of all this? It is undoubtedly fascinating to read of these bizarre cases and learn about the intricate neural machinery that underlies our normal experience. It is also, in my opinion, perfectly acceptable to propose bold speculations about what might be going on, even if the speculation seems unfounded or far-fetched; as Ramachandran frequently remarks, science thrives on risky conjecture. But there are times when the impression of theoretical overreaching is unmistakable, and the relentless neural reductionism becomes earsplitting. This is progressively the case as the book becomes more ambitious in scope. Ramachandran will often qualify his more extreme statements by assuring us that he is only proposing part of the full story, but there are moments when his neural enthusiasm gets the better of him.

For instance, mirror neurons are clearly an interesting discovery, but are they really the explanation of empathy and imitation?* Isn’t much more involved? Does an expert impersonator simply have more (or more active) mirror neurons than the average human? What about the ability to analyze an observed action, not merely repeat it? Where does flexibility in deepness of imitation come from (it cannot be those reflexive mirror neurons)? Imitation, moreover, comes in many forms, of different degrees of sophistication, and we cannot assimilate the trained mime to the baby’s reflex of poking out her tongue at the sight of her mother doing the same.

The discussion of art seems largely about another subject entirely—what elicits human attention. What about the place of abstract art in the history of painting? There is much more to it than gulls and red dots. In the case of language, one wonders how the bouba-kiki effect will explain words that have nothing in common with what they denote—the vast majority of cases. And how can anything about neurons firing in the brain account for conscious experience?

Ramachandran acknowledges no limit to neural reductionism, but there is a very big issue here that he slides over: the mind–body problem. His suggestion that by identifying the part of the brain involved in voluntary decision we turn a philosophical problem into a neurological one could only be made by someone who does not know what philosophical problem is in question—to put it briefly, whether or not determinism conceptually rules out freedom of the will. That question cannot be answered by pointing to one case of brain damage or another. Learning about the parts of the brain responsible for free choice will not tell us how to analyze the concept of freedom or whether it is possible to be free in a deterministic world. These are conceptual questions, not questions about the form of the neural machinery that underlies choice. His book has all the charm of an enthusiast’s tract—along with the inevitable omissions, distortions, and exaggerations.

There is another theme running through the book about which I think Ramachandran is insufficiently thoughtful. His subtitle is “A Neuroscientist’s Quest for What Makes Us Human” and he repeatedly asks what makes us “unique” and “special.” The question is muddled. If the word “human” is just the name for the biological species to which we belong, then the answer presumably is our DNA—just as DNA is what makes tigers tigers. Species identity is a matter of genetics. If we ask instead what makes humans unique, then that question too is poorly posed: every species is unique, since no species is another species. Tigers are as uniquely tigerish as humans are uniquely human.

Ramachandran comes closer to his intended question when he speaks of our “marvelous uniqueness”: that is, he is asking what makes us superior to other species. I have three comments about this formulation. First, it risks anthropocentrism of a dubious (and possibly pernicious) kind: Aren’t certain other species superior to us in some respects—speed, agility, parenting, fidelity, peacefulness, or beauty? Just because a trait such as advanced mathematical ability belongs to us alone is no reason to claim some transcendent value for that trait. One would need to see some sort of defense of the claim that what is peculiar to us is thereby uniquely valuable. Is there really, in the end, a sensible notion of species superiority?

  1. *

    Patricia S. Churchland in Braintrust: What Neuroscience Tells Us About Morality (Princeton University Press, 2011) is commendably cautious about the explanatory power of mirror neurons to explain imitation and empathy (see chapter 6), though she is in general a neural enthusiast. 

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