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Inside the Executive Brain

1.

In 1967, Elkhonon Goldberg, then a twenty-year-old student of neuropsychology in Moscow, met a young man, another student only a few years older than himself. Vladimir, Goldberg tells us, had been standing on the platform of the Moscow subway, tossing a soccer ball from hand to hand, when the ball fell onto the rails. Jumping down to retrieve it, Vladimir was hit by a train and sustained severe damage to the front part of the brain, the frontal lobes, both of which had to be amputated.

The career of every clinician,” Goldberg writes, “is punctuated by a few formative cases. Vladimir was my first formative case. Unwittingly, through his tragedy, he introduced me to the rich phenomena of frontal-lobe disease, triggered my interest in the frontal lobes, and so helped shape my career.” While Vladimir spent most of his time staring blankly into space (though when disturbed he might release a stream of profanities or hurl a chamberpot), Goldberg found that he could sometimes engage him with “a casually profane, locker-room-style banter…[and] a friendship of sorts developed between a brain-damaged student and a student of brain damage.”

Goldberg’s mentor, the great Russian neuropsychologist A.R. Luria, was becoming increasingly interested in the frontal lobes, considered to be the “highest” parts of the brain, and suggested that his study might become Goldberg’s project too. This project has now lasted a third of a century, and has taken Goldberg into some of the profoundest and strangest realms of brain-mind functioning and its mishaps. Like Luria, he has employed a mixture of specially tailored and ingenious tests with minute naturalistic observation, alert to the vagaries of frontal lobe function not only in the clinic but in the streets, in restaurants, in the theater, everywhere. (Goldberg speaks of himself here as a “cognitive voyeur.”) All this is leavened with exceptional imaginative and empathic powers, in his effort to see the world through his patients’ eyes. With thirty years of observation and experience, he has achieved a level of insight which, one feels, would have delighted and amazed his mentor, Luria.

In his new book The Executive Brain: Frontal Lobes and the Civilized Mind,1 Goldberg takes us on a journey, his own journey, from those early Moscow days to the present, a journey at once intellectual and personal. He provides a brilliant exposition of the complex functions of the frontal lobes, the most recently evolved and especially human part of the brain, examining the great range of frontal lobe “styles” in normal people, the tragic incidents that may occur with neurological disease or brain damage, the ways in which their function can be tested, and, not least, the ways in which they can be strengthened—many of which Goldberg himself has pioneered, not only in brain-damaged patients but in those with healthy brains as well.

Goldberg’s notions of “cognitive fitness”—having one’s cognitive faculties honed, available, maximally efficient—and a “cognitive gym,” with a series of visual and intellectual computer games and exercises, are particularly challenging and important. Rich case histories, along with brief but revelatory neuropsychological anecdotes, form the narrative heart of the book, but they are frequently interleaved with personal narratives of every sort. This makes The Executive Brain a highly engaging and intimate memoir, a sort of intellectual autobiography no less than a grand piece of scientific reporting and “popular” science.

The Executive Brain is dedicated to Luria, and opens movingly with a memory of a conversation with him in 1972—Goldberg was twenty-five at the time, and Luria seventy, at once his illustrious mentor and a most affectionate and supportive father figure. Luria pressed Goldberg to join the Communist Party, offering to nominate him, and underscored the necessity of this for any career advancement in the Soviet Union. (Luria was himself a member of the Party, more from expedience, perhaps, than from conviction.) But Goldberg was (and remains) a rebel at heart, not disposed to make compromises, however advantageous, if they went against his inner instincts. Such intransigence was costly in the Soviet Union, and had landed his father in the Gulag.

After putting Luria off a dozen times, he finally told him outright that he would not join the Party. Further—though this, of course, he did not say—he had decided to leave Russia, despite a profound love for his motherland and language. It was virtually impossible for a highly valued member of society, a doctoral student at Moscow University, to leave the country. But Goldberg left Moscow University, left Moscow, and worked at a menial job, changing his identity from that of an intellectual to that of an unskilled laborer. His story of how he did this, and in a way that would avoid compromising Luria in any way, forms the extraordinary and compelling introduction to The Executive Brain, a book which ends twenty-six years later, in 1998, with a return visit to Moscow and the country he left half a lifetime before.

2.

It is only in human beings (and great apes, to some extent) that the frontal lobes, the most recently evolved part of the nervous system, reach so striking a development. They were also, by a curious parallel, the last parts of the brain to be recognized as important—even in my own medical student days, they were called “the silent lobes.” “Silent” indeed they may be, for they lack the simple and easily identifiable functions of the more primitive parts of the cerebral cortex, the sensory and motor areas, for example (and even the “association areas” between these), but they are overwhelmingly important. They are crucial for all higher-order purposeful behavior—identifying an objective, projecting a goal, forging plans to reach it, organizing the means by which such plans can be carried out, monitoring and judging the consequences to see that all is accomplished as intended.

This is the central role of the frontal lobes, one which releases the organism from fixed repertoires and reactions, allows the mental representation of alternatives, imagination, freedom. Thus the metaphors that run through Goldberg’s book: the frontal lobes as the brain’s CEO, capable of taking “an aerial view” of all the other functions of the brain and coordinating them; the frontal lobes as the brain’s conductor, coordinating the thousand instruments in the brain’s orchestra. But above all, the frontal lobes are the brain’s leader, bringing the person into the novelty, the innovations, the adventures of life. Without the great development of the frontal lobes in the human brain (coupled with the development of the language areas), civilization could never have arisen.

The ability of the individual to form intentions is invested in his frontal lobes, and these are crucial for higher consciousness, for judgment, for imagination, for empathy, for identity, for “soul.” Thus in the famous case of Phineas Gage—a railway foreman who while setting an explosive charge in 1848 had a two-foot tamping iron blown through his frontal lobes when the charge backfired—Gage’s intelligence was preserved as well as his ability to move and talk and see.2 But there were other, profound changes in him. He became reckless and improvident, impulsive, profane; he could no longer plan or think of the future; and for those who had known him before, “he was no longer Gage.” He had lost himself, the most central part of his being, and (as is the case with all patients with severe damage to the frontal lobes) he did not know it.

Such an “anosognosia,” as it is called, is at once a mercy (such patients do not suffer or anguish over or lament their loss) and a major problem, for it undercuts understanding and motivation, and makes attempts to remediate the condition much more difficult.

Goldberg also brings out how, because of the unique richness of the frontal lobes’ connections to different parts of the brain, other conditions which have their primary pathology elsewhere, even in the subcortex, may evoke or present themselves as frontal lobe dysfunctions. Thus the inertia of parkinsonism, the impulsiveness of Tourette’s syndrome, the distractibility of ADHD (Attention Deficit Hyperactivity Disorder), the perseveration of OCD (Obsessive-Compulsive Disorder), the lack of empathy in autism or chronic schizophrenia—all can be understood, in large part, Goldberg feels, as being caused by the resonances, the secondary disturbances, in the function of the frontal lobes. Much evidence is adduced in favor of this view, not only from clinical observation and testing but from the latest results in functional brain imaging, and Goldberg’s insights here illuminate these syndromes in a new way, and may be very important in clinical practice.

While patients with massive frontal lobe lesions show an unawareness of their condition, this is not so for patients with parkinsonism, Tourette’s syndrome, OCD, ADHD, and for many with autism; indeed such patients can articulate and often analyze with great accuracy what is going on in themselves. Thus they can tell us what patients with primary frontal lobe pathology cannot—what it actually feels like from the inside to have these differences and vagaries of frontal lobe function.

Goldberg presents these discussions, which might otherwise be difficult or dense, with great vividness and humor, and with frequent accounts of his own experience. He tells the story of Charlie, a previously puritanical young ex-Marine, who, following a heart injury, commits a hold-up so inept, so imprecise, that he is caught, inevitably, almost immediately. Goldberg calls this a “frontal lobe crime,” but the court that sentences Charlie has no more realization than his family, or Charlie himself, that his crime, his changed behavior, was a consequence of his head injury. Later, in the prison rehab center, Charlie offers penis-shaped lollipops to all the female employees, his “id,” as Goldberg says, no longer under the control of his frontal lobes.

Then there is the story of Kevin, a successful executive who was thrown from his horse in Central Park. When he awoke from a ten-week coma, Kevin was in some ways reduced to the emotional level of a boy—“he [now] related to his wife like a twelve-year-old, and competed with his children for her attention…[and] in many ways interacted with his own children as an equal”—while retaining the powers and desires of a man. At other times, he behaved like an automaton, ordering, for example, every item on a menu, not because he wanted them all but because they were there, in his perceptual “field,” and he had no choice but to respond in this enforced, helpless fashion.

In the midst of his discussion of “field-dependent” behavior, and of the incontinent distractibility so characteristic of those with severe frontal lobe damage, Goldberg speaks of dogs and their relatively “afrontal” behavior, where “out of sight” is “out of mind.” He contrasts this with the behavior of apes, and tells us how, on a trip to Thailand, he once “befriended and was befriended by” a young male gibbon, the pet of a restaurant owner in Phuket:

Every morning the gibbon rushed forth to shake hands. All limbs and a small body, he would then engage in a brief spider-like dance, which, in my self-flattering way, I interpreted as an expression of joy at seeing me. But then, despite his proclivity for restless play, he would settle next to me and with extreme concentration would study the minute details of my clothes: a watchband, a button, a shoe, my glasses (which, in one of my unguarded moments, he took off my face and tried for lunch). He stared at the items intently and systematically shifted his gaze from one detail to another. When one day a bandage appeared around my index finger, the young gibbon studiously examined it. Despite his status of a “lesser” ape (in contrast to the bonobos, chimpanzees, gorillas, and orangutans, which are known as the “great” apes), the gibbon was capable of sustained attention.

Most remarkably, the gibbon invariably turned back to the object of his curiosity following a sudden distraction, say, a street noise. He would resume his exploration precisely where it had been interrupted, even when the interruption was more than a split second in length. The gibbon’s actions were guided by an internal representation, which “bridged” his behavior between before and after the distraction. “Out of sight” was no longer “out of mind”!

Goldberg is a dog lover, and has owned several dogs, but for him “the interaction with the gibbon was so qualitatively different from, and so strikingly richer than, anything I had ever experienced with dogs, that I briefly entertained the idea of buying the gibbon and bringing him to New York to be my pet and companion.”

This proved to be impossible, and Goldberg (whom I knew by this time) was very sad that he could not do so. I felt a great sympathy for him because I had had an almost identical experience with an orangutan myself, and had more than half-wished we could at least send postcards to each other.

3.

There are other major themes in The Executive Brain which first surfaced when Goldberg was a student, and which he has been exploring and elaborating ever since. These have to do with the different sorts of challenge which an organism faces: not only novel situations (and the need to arrive at novel solutions), but also the need to have set, economical routines for dealing with familiar situations and demands. Goldberg sees the right hemisphere of the brain as especially well equipped to deal with new situations and solutions, and the left side of the brain with routine tasks and processes. There is, in his view, a continual cycling of information, of understanding, from the right to the left hemisphere. “The transition from novelty to routinization,” he writes, “is the universal cycle of our inner world.” One sees this whenever a new skill is learned—driving a car, playing an instrument, identifying ferns—all of which become “automatic” after a while. This runs counter to the classical notion that the left hemisphere is the “dominant” one and the right hemisphere the “minor” one, but it is consistent with the clinical finding that damage to the right hemisphere may have much stranger and profounder effects than the relatively straightforward effects of damage to the “dominant” hemisphere. Thus it is the integrity of the “minor” hemisphere, so-called, which Goldberg feels is particularly crucial for the sense of self or identity—its integrity, and the integrity of the frontal lobes.

Another central theme of The Executive Brain is related to what Goldberg sees as the two radically different, but complementary, modes of cerebral organization. Classical neurology (and its precursor, phrenology) sees the brain as consisting of a multitude, a mosaic, of separate areas or systems or modules, each dedicated to a highly specific cognitive function such as color vision, and all relatively isolated, with very limited interactions. Such an organization is evident in the more primitive parts of the brain, such as the thalamus (which consists of many discrete and separate nuclei) and the older parts of the cerebral cortex. Thus small, discrete lesions in the visual cortex can produce equally discrete losses of color vision, movement vision, depth vision, etc. But such a system, Goldberg argues, would be rigid, not flexible, and have little capacity to deal with novelty or complexity, to adapt or learn. Such a system, he maintains, would be wholly inadequate to support identity or higher mental life.

Already in the 1960s, as a student, Goldberg was starting to envision a very different sort of organization in the newer and “higher” parts of the brain, the neocortex (which starts to develop in mammals and reaches its highest development in the human frontal lobes). A careful analysis of the effects of damage to the neocortex suggests that there are no longer discrete, isolated modules or domains here, but rather a gradual transition from one cognitive function to another, corresponding to a gradual, continuous trajectory along the cortical surface.

How do we recognize a thing—a hat, a flower? It is easy to show that there is no single location, no module, no “hat center,” so to speak, in the brain. For if a patient develops a so-called visual agnosia (as did my patient, the man who mistook his wife for a hat), he may be unable to recognize anything visually, even though the elementary visual sensations (and even the capacity to draw) are perfectly intact. But as soon as other senses are called into action—the sense of touch, or hearing, or smell, or taste—the object is recognized, categorized, without the least difficulty. Thus the look of a hat and the feel of a hat are separately represented in the brain, and one may lose one without the other. One’s mental representations are not located in a single spot but are distributed widely on the surface of the cortex—and yet the areas for visual recognition, for tactile recognition, for audio recognition, all slide into one another, grade continuously. All interact, all are orchestrated, normally, into a seamless unity.

Thus Goldberg’s central concept is one of a cognitive continuum, a gradient. This radical idea enthralled the young Goldberg the more he thought of it: “I began to think of my gradients as the neuropsychological analogue of the Mendelev periodic table of elements.” This theory of gradients was incubated and tested for twenty years, and was only written up by Goldberg in 1989, when he had gathered much detailed evidence to support it. But the groundbreaking paper in which he launched his theory was largely ignored, despite the great explanatory power it promised.

When I wrote an essay in 1995 about “forgetting and neglect” of discoveries in science, I cited, among many other examples of it, the failure to comprehend or see the relevance of gradiential theory when it was published.3 Luria himself found it incomprehensible in 1969, when Goldberg first presented it to him. But there has been a great change, a paradigm shift (as Kuhn would say) in the last decade, partly connected with theories of global brain function such as Ger-ald Edelman’s,4 partly with the development of neural nets as modeling systems, or “massively parallel” computer systems, i.e., systems capable of performing complex analyses with hundreds of variables (as, for instance, with global weather prediction). The concept of interacting cerebral gradients rather than isolated modular functions—Goldberg’s vision as a student—is now much more widely accepted.

Modularity still exists, Goldberg emphasizes, as a persistent but archaic principle of cerebral organization, which was gradually supplanted or supplemented by a gradiential principle later in evolution. “If this is so,” he remarks, “then an uncanny parallel exists between the evolution of the brain and the intellectual evolution of how we think about the brain. Both the evolution of the brain itself and the evolution of our theories about the brain have been characterized by a paradigmatic shift, from modular to interactive.”

Goldberg wonders whether this shift may find parallels in political organization, with the breakup of large “macronational” states to smaller “microregional” states, a change which threatens anarchy unless a new supranational executive—the political equivalent of the frontal lobes—can arise and coordinate the new order of the world. He wonders too whether the replacement of the enormous but relatively few and isolated supercomputers of the 1970s by the hundreds of millions of personal computers which we have now, all potentially interacting, parallels the shift from modular to interactive, with search engines as the digital equivalent of frontal lobes.

The Executive Brain ends as it begins, on a personal and introspective note, with Goldberg’s memory of how as a boy he read Spinoza in his father’s library and loved his calm equation of body and mind; and how this played a crucial part in directing him toward neuropsychology, and avoiding the fatal splitting of body and mind, the dualism which Antonio Damasio calls “Descartes’ error.” Spinoza had no sense that the human mind, with its noble powers and aspirations, was in any sense devalued or reduced by being dependent on the operations of a physical agency, the brain. One should rather, he said, admire the living body for its wonderful and almost incomprehensible subtlety and complexity. It is only now, at the dawn of the twenty-first century, that we are beginning to get the full measure of this complexity, to see how nature and culture interact, and how brain and mind produce each other. Only a small handful of remarkable books address these central problems with great force—those of Edelman and Damasio at once come to mind. To this select number, Elkhonon Goldberg’s book The Executive Brain should surely be added.

  1. 1

    Published this March by Oxford University Press. This essay appears in different form as the foreword.

  2. 2

    The case of Gage is discussed in Antonio Damasio’s book Descartes’ Error: Emotion, Reason, and the Human Brain (Putnam, 1994).

  3. 3

    Scotoma: Forgetting and Neglect in Science,” in Hidden Histories of Science, edited by Robert Silvers (New York Review Books, 1995).

  4. 4

    See, for example, among Edelman’s books, Bright Air, Brilliant Fire (Basic Books, 1992).

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