What causes a woman’s own hand to try to strangle her? How can a grown man recognize a carrot but not be able to name it? Such mysteries of the brain and mind are being probed by Martha Farah and Todd Feinberg, pioneers in the brave new world of neuropsychology.
By John Shea | Illustration by Laurent Cilluffo
IF DR. MARTHA FARAH’S grandfather hadn’t taken a serious blow to the head many years ago, she might not have found herself studying how the mind works and how damage to the brain affects perception and behavior.
As Farah tells it, her immigrant grandfather had a keen business acumen, which he used to make millions. During that heady time, the family had moved from Canada to a mansion in New York City — only to return, penniless, when he lost it all. Until recently, she assumed that he had lost his fortune in the stock-market crash of 1929. But then she learned that his financial world had collapsed before Wall Street did.
“My aunt told me that he’d been in a car accident, was knocked unconscious, and afterwards made a string of losing deals,” recalls the 42-year-old Farah, now professor of psychology at Penn. “She said his accountant begged him to stop trying to make money: ‘Mr. Farah, just put it in the bank and live on it!’” Unfortunately for his family, he did not take the advice.
Farah also learned that her grandfather had developed a bad temper. Once at dinner, she says, “someone said something to annoy him, and he stood up, went to the china cabinet — full of Limoges! — picked it up, and hurled it across the dinner table.”
Farah, described by a colleague in the Medical Center as “one of the most outstanding cognitive neuroscientists in the world,” immediately recognized the symptoms described by her aunt. “Neuropsychologically, this all hangs together,” she says. “The poor judgment and the lack of impulse-control are familiar signs of prefrontal damage.” People who have suffered frontal-lobe damage can seem quite unaffected on the surface — normal speech, memory, and so forth. “Yet despite so many intact abilities, prefrontal damage often robs people of what you’d call ‘judgment’: the ability to weigh multiple factors in complex, real-life situations and act accordingly.” Even “business sense” can vanish. The prefontal damage, she adds, “can also wreak havoc with their emotional life and their self-control” — as everyone at the dinner table that night must have noted.
“So you see,” Farah concludes, “if the brain were organized differently, and prefrontal function were not so crucial to judgment and decision-making, I’d be a rich woman today!” And without that wolf at the door, she might never have found herself working in the psychology department, exploring the brain and the mind and the relationship between the two.
Farah’s own career is a case study in crossing disciplines — even now, she has secondary appointments in the School of Medicine’s departments of neurology and psychiatry — and she feels very strongly that the interdisciplinary approaches are essential for the field to advance. Asked how she came to do what she’s doing, she begins by saying she took “a pretty circuitous route.” At the Massachusetts Institute of Technology, she majored both in metallurgy and philosophy. While enrolled in a course on the history of physics, she was especially taken by the major figures of the 17th century: “What I envied was that they were both doing the science and thinking hard about the whole process of doing science” — and they were grappling with the basic elements of their field.
So she decided to find “a nice, immature science” that offered her similar opportunities. “Psychology seemed to be it,” she says, adding that she continues to see the field that way. “We’ve got pretty good beginnings, but there are still vast stretches of terrain we don’t know.”
Part of what attracted Farah to cognitive psychology, which focuses on the study of the mind and information-processing, is that one is constantly being forced to go back to “the first principles.” Researchers must continually confront the relation of data to theory — both of which, she asserts, have changed radically in recent years. Much of traditional cognitive psychology involved studying “normal” subjects performing simplified tasks. While it is “quite amazing how much you can figure out with that very impoverished data,” she says, a wider subject-group offers even more. Among neuropsychologists, she says, “probably the oldest, most time-honored” approach is to study the effects of brain lesions on cognition and behavior. While pinpointing those lesions once depended largely on autopsies, in the last 15 years, new noninvasive brain-imaging techniques like positron emis- sion tomography (PET) and functional magnetic resonance imaging (fMRI) have allowed scientists to observe the human brain in action and with more precision.
BACK AROUND 1979, when Farah was a graduate student in experimental psychology at Harvard University, she asked permission to cross-register for a course in neurology. Her adviser responded by telling her that she obviously hadn’t understood the basic principle of cognitive psychology — that the mind is “software,” and that she wasn’t going to learn anything about it by looking at the brain, which is the “hardware.” That was the received knowledge at the time — and yet by then, according to Farah, psychologists had already reached an impasse, unable to answer some of the field’s fundamental questions while needing more real-life checks on their theories. Neuroscientists, on the other hand, knew all about the brain’s neurons and synapses, but lacked the theories to assemble the masses of complex knowledge.
Since then, there has been what Farah calls a “scientific revolution,” and the two groups of scientists who once had “nothing to say to each other” are now “falling all over each other” to collaborate. At Penn, she notes, the Biological Basis of Behavior has become one of the most popular majors for undergraduates, while both the David Mahoney Institute of Neurological Sciences and the Institute for Research in Cognitive Science have been trying to create bridges among psychologists, information scientists, and neurologists.
Some 12 years ago, when Farah was a postdoctoral student at MIT, she got a call from a behavioral neurology fellow at the University of Florida named Todd E. Feinberg, C’74. Feinberg, now chief of the Yarmon Division of Neurobehavior and Alzheimer’s Disease at Manhattan’s Beth Israel Medical Center, had heard from his adviser that Farah was studying mental imagery, a subject he wanted to know more about. So he “just kind of called me out of the blue,” in Farah’s words. The two have stayed in close touch over the years, and when McGraw-Hill asked Feinberg to edit a new textbook on neuropsychology a few years ago, he asked Farah to be his co-editor.
Her first response was to say no. But when she thought about it some more, it occurred to her that many neurologists “still get 19th-century education in medical school when it comes to how the mind works.” Working on the textbook, she felt, would be a great opportunity to bring some of the newer, evidence-based cognitive theories to neurologists and clinicians. So she signed on with Feinberg, and last year McGraw-Hill published their 873-page Behavioral Neurology and Neuropsychology, which received a four-star (“excellent”) rating from the Mayo Clinic Proceedings and kudos for its interdisciplinary approach and fusion of theory and clinical practice. (A reviewer in The New England Journal of Medicine, for example, praised the pair’s efforts to integrate traditional behavioral neurology and modern cognitive neuropsychology, and said that the result was a “comprehensive and comprehensible textbook.”)
Consider the following passage from the chapter by Dr. Marcus E. Raichle, professor of neurobiology at Washington University School of Medicine, who pointed out that current brain-mapping studies are not merely a modern version of phrenology, in which single areas of the brain were thought to represent specific thought-processes and emotions. Instead, writes Raichle, “just as diverse instruments of a large orchestra are played in a coordinated fashion to produce a symphony, a group of diverse brain areas, each performing quite elementary and unique mental operations, work together in a coordinated fashion to produce human behavior.”
But when one of those instruments gets damaged, the symphony can turn strangely discordant.
IT IS THE STUFF of nightmares … and horror movies. A woman awakens from a troubled sleep; it is dark; a hand tightens around her neck, vicious and implacable; with her right hand, she tries desperately to pull it off. And then, as she struggles, she realizes who her assailant is: her own left hand. Even after she pulls it away, she is too frightened to fall back asleep.
This scenario describes some of the more extreme behavior associated with an unusual condition known as Alien Hand Syndrome (AHS). When The Learning Channel presented a show on AHS about a year and a half ago, the first expert featured was Feinberg.
“I thought by studying this disorder, we could really learn something about how the mind on the one hand and the brain on the other hand interact and work together,” said Feinberg, who, besides his appointment at Beth Israel Hospital, is also associate professor of neurology and psychiatry at Albert Einstein College of Medicine. “Alien Hand Syndrome is a disorder where one hand, the left or the right, acts in a fashion which the patient feels is out of their control. For instance, the left hand would do things that the patients themselves feel they’re not performing, actions which are against the patients’ conscious intentions.”
While many people with AHS have had radical brain surgery to treat severe epilepsy, Feinberg says it can happen to anyone who has had brain damage. The case of the woman whose hand attempted to strangle her goes back to the earliest study of the disorder, written in Germany in 1908; but in matter-of-fact fashion, Larry, one of the patients on the show, also reported waking up one night to find his left hand around his neck. Sometimes when he is trying to eat, recalled Larry, his left hand will grab his right hand “and just won’t let me get a fork- or spoonful of food.”
Feinberg and the other experts trace AHS to the corpus callosum, the large bundle of nerve fibers that links the left and right cerebral hemisphere. During the radical surgery that Larry underwent, the corpus callosum was split. “The key to the alien hand is the notion that you can have two consciousnesses in a single individual,” says Feinberg. And by cutting the corpus callosum, “you potentially have divided the mind.”
While Farah has pushed to bring more clinical evidence to bear on theories about the mind, Feinberg has moved from clinical work to more theoretical investigations.
“As a behavioral neurologist,” he explains, “my basic data-base is patients with brain lesions” from head injuries, tumors, or anything else that disrupts the brain’s processing. He is interested in how brain damage affects their personality and how they view the world. But lately he has been taking a larger view, the study of consciousness itself, and last year he was guest editor of an issue of a professional journal, Seminars in Neurology, which focused on consciousness.
Yet that, as he tells it, has been his abiding interest all along. Both of his parents were psychologists, and he has always been fascinated by “the idea that I had a mind” — such a seemingly immaterial thing that plays such a huge part in making us who we are. As an undergraduate at Penn, he was caught up in entertainment, performing with several students who went on to careers in music, comedy, and other creative fields. While he knew that his father would have had a “total M.I.” (heart attack) if he had gone into show business, he does still find occasional ways to combine his interests. For a chapter heading in his book in preparation, “Altered Egos,” Feinberg quotes from the Talking Heads song “Once in a Lifetime”:
And you may find yourself behind the wheel of a large automobile
And you may find yourself in a beautiful house, with a beautiful wife
And you may ask yourself — Well … how did I get here?
To Feinberg, these lines suggest a psychological experience called the Capgras syndrome, a feeling of dislocation and disconnection. This syndrome and several others are common subjects of Feinberg’s research into consciousness. And he has been struck by the way literature over the centuries reflects, in his words, these “perturbations of the self” — often long before any psychologists were there to coin their names.
ONE OF FEINBERG’S Capgras-syndrome cases, for example, is eerily reminiscent of Poe’s “William Wilson,” in which the protagonist is tormented by his double. Feinberg’s case involves S. M., a 77-year-old woman who had been deaf since the age of five. She was found signing in front of the mirrors in her home and explained that she was communicating via sign language with “the other S. M.” This double, she explained, was identical to her, also deaf — but not as “bright.” As Feinberg writes in Seminars in Neurology, S. M. was “presented with a stimulus that should be quite familiar and that indeed can be verified as being familiar” — her own image. Yet she “still claims an estrangement, alienation, or disavowal from the object.”
The most common perturbation encountered by the neurologist in clinical practice, says Feinberg, is asomatognosia, which literally means “lack of recognition of the body.” Asomatognosic patients do not recognize a portion of their bodies — even more, they often actually disavow those parts and sometimes develop stories to explain their dissociation from their own bodies. Feinberg calls this phenomenon “personal confabulation”: a falsification that the falsifier believes to be true.
Since the right side of the brain controls the left side of the body, Feinberg points out, the left arm is by far the most commonly rejected or misidentified part of the body among patients who have suffered damage to the right hemisphere. And some of the brain-damaged patients he videotaped had a condition known as hemispatial neglect, in which they ignore stimuli in the area of space on the side opposite to a brain lesion.
One patient, a 64-year-old construction worker with a right-hemisphere stroke and paralysis of his left arm, even denied he was ill (a condition known as anosognosia). Although Feinberg informed him that he was in Beth Israel Medical Center, the patient insisted he was at his job site. Then he volunteered information that he apparently believed but was subsequently found to be false: “My mother’s in the hospital right now … She had a stroke while she was in the hospital.” And when Feinberg lifted the patient’s paralyzed left arm and asked what it was, the patient replied: “My mother-in-law’s hand. Someone’s hand.”
To Feinberg, the appearance of the mother and mother-in-law in the patient’s account suggests that there are other issues involved besides paralysis from stroke. In similar cases, he says, some health professionals might attribute all the patient’s behavior to brain damage; but in Feinberg’s view, “the pre-morbid personality is very important.” Physicians and family members, he cautions, must try to learn “what the patient brings to the table” before the brain damage.
In a way, Feinberg’s willingness to draw upon different disciplines could be seen as a response to the dominant theory when he was an undergraduate. “The big thing in 1973 and ’74 was behaviorism,” he says. “I couldn’t stand it.” For all its attempts to be scientific, he found behaviorism terribly reductive. Now, he feels, with the coming together of cognitive psychology and neuroscience, the urge to be scientific in explaining psychological disorders has a stronger foundation.
A particularly haunting case that Feinberg videotaped features a woman in her seventies who was admitted to Mount Sinai Hospital. After an acute stroke involving her right hemisphere, her left arm was paralyzed. She persistently identified her left arm as Feinberg’s or as a “breast” or a “deodorant.” She also spoke frequently of her fears of being ill and dying, and Feinberg notes that she developed an elaborate personal confabulation regarding her dead husband and his hands. In fact, the patient insisted that her husband had left her his hands in his will: “He just left them like he left his clothes.” As a result, she said, she recently put them in the garbage.
Why, she was asked, had she got rid of them after all those years? “Because I got the stroke — and I thought maybe I’d die here like he did!”
As Feinberg sees it, the patient finds it difficult to talk about her own illness directly; thus, she denies that the paralyzed arm is hers while she confabulates a story about her dead husband’s inanimate hands. Her case, says Feinberg, also illustrates the Fregoli syndrome, in which the patient insists that someone who is actually unfamiliar to her is someone whom the patient really knows — a little like The Wizard of Oz, in which Dorothy receives a blow to the head during the tornado and is “transported” to another world. The unfamiliar — the Tin Man, the Cowardly Lion, and so on — seem uncannily familiar, and when Dorothy “returns” to Kansas, she recognizes them among her everyday acquaintances: “You were there, and you were there!” Where the Capgras syndrome suggests a feeling of jamais vu, a sense of never having seen something before, the Fregoli syndrome suggests deja vu.
IF SOME OF Feinberg’s cases have an inherent spookiness, some of Farah’s almost have a comical aspect — and not just because the patients she sees are usually in less dire circumstances. She gets her cases in two basic ways, she explains. Usually she tells her colleagues at the Medical Center that she’s looking for patients who cannot recognize faces or printed words. (One patient Farah has seen can write — but then is unable to read what he’s just written!) But occasionally she hears of cases by chance — and with those, she says, “you stand to learn a lot” and stretch a little bit as a scientist. She proceeds to offer “a pretty wild example” of just such a serendipitous case, referred by a speech therapist who was helping a patient with his reading problems.
When Farah and one of her graduate students, Marcie Wallace, began showing the new patient a series of cards with pictures of everyday objects, he seemed to recognize the pictures, occasionally fretting for the right word. But then they noticed something odd: the man had a particularly difficult time naming the picture of a carrot. His pause, says Farah, was agonizing; he waved his hands, listing several properties of a carrot while at a loss to name it. Since Farah’s main interest has been in vision and the interface between vision and thought — her previous book was Visual Agnosia: Disorders of Object Recognition and What They Tell Us about Normal Vision (1990) — she had approached the new patient with an eye toward the visual-processing aspects, those involved in reading. But this patient could visually process — it was coming up with the name that was the problem.
While that kind of block is not unusual in patients with brain damage, Farah and Wallace discovered a pattern: either he could not name any of the fruits and vegetables in the deck of cards, or it would take him more than 10 seconds of evident struggle. By coincidence, the researchers had just read about a similar problem in a scientific journal — which they had both initially dismissed as impossible! As Farah puts it, how could the brain be so organized that a lesion affected only a person’s ability to name fruits and vegetables? Given their own skepticism about the earlier study, Farah and Wallace were cautious.
First they ruled out “potential confounds that had been in the original report” — factors that might have provided other possible explanations for the man’s condition. Then, to determine whether it was the pictures and not the fruits and vegetables themselves that the patient could not name, Farah and Wallace bought a couple of bags of groceries and had him try to identify the real things. “It didn’t matter what the input modality was,” says Farah. The patient’s brain continued to stumble in this highly restricted area.
The condition, which came after the patient suffered a stroke, baffled him as much as it did the researchers. Their studies convinced Farah that the brain’s naming system is semantically organized — by categories of meaning — and implemented in the brain “in such a way that different little localized bits of tissue evidently represent names from different categories.” And all it takes, she says, is “just the right kind of lesion coming along in just the right place [to] knock out your ability to retrieve names from that category.” It could almost be an absurdist skit by Steve Martin, Farah’s “idol”: the brain’s fruits-and-vegetables naming-site located right next door to the site for naming farm animals.
Another unusual disorder that Farah studies is prosopagnosia, the inability to recognize faces. It is caused by damage to two very specific areas located symmetrically on either side of the brain, on its inferior surface. “The most astonishing thing about these people is that they can recognize most everything else,” says Farah. A patient she studied for years, L. H., had been in an accident. Despite brain damage, he got on with his life so successfully that he finished college and earned two master’s degrees. With one significant change: he can walk right past family members and not recognize them. Often, he must identify them by characteristic clothing. But that’s not always possible. Farah reports that L. H. coached soccer after his accident — and when his own children were in uniform, he could not tell them from others on the team. And at a party once, he offended a woman by walking up to her and saying, “Come on, honey, let’s go home.” She was not his wife. While that may not seem quite as dramatic a misidentification as that made by the title character in Oliver Sacks’s The Man Who Mistook His Wife for a Hat, Farah expresses great sympathy and admiration for this person who looks in the mirror “and sees an unfamiliar-looking face there.” Despite his brain damage, she reports, the man retains a high IQ and a good memory and has a career in the mental-health field. He’s also highly adept at “visual-spatial processing,” such as reading maps and solving mental “rotation” tests.
Another memorable patient, C.T., had suffered a head injury in a motorcycle accident and appeared not to recognize faces. Eventually, however, Farah’s team discovered that he could recognize some famous faces from before his injury. In fact, he could identify photos of the young Michael Jackson taken before the time of C.T.’s brain injury — which showed the singer with a broad nose and an Afro hairstyle — but he could not identify photos of Jackson taken after his cosmetic makeover!
According to Farah, the parts of the brain that originally do the work of perceiving faces are certain areas of the inferior temporal cortex. That perceptual information is then projected to the hippocampus and surrounding structures, where it is processed in a way that remains, in Farah’s word, “mysterious.” That processing enables the information to take a permanent form back in the area where the original analyzing took place, the inferior temporal cortex. Given that division of labor, if there were an anatomical disconnection as the result of trauma, the brain would be able to perceive new faces, but not remember them; yet it would be able to perceive and remember everything that is not a face. In tests, C.T. fared very well on recognizing objects and “old” faces, but with faces from after his accident, he was “just terrible.” Farah dubbed it a case of prosopamnesia — amnesia of faces — the first one ever recorded.
WHAT THE RESEARCH on prosopagnosia implies, says Farah, is that “the systems that you need to do face recognition are separate from what you need to do object recognition.” That “flies in the face of the last 20 years of vision research,” she notes; partly because all scientists are “lovers of parsimony,” cognitive psychologists have been searching for a single processing mechanism for visual recognition. As she puts it, “It doesn’t feel like you’re doing anything differently when you look at a face or at a chair … We feel like we’re one whole seamless self; and yet, when you study the effects of brain damage, you realize that that feeling has got to be in some sense illusory. What we really are is a collection of various specialized processors.” When all of them are working together smoothly, one doesn’t notice the diversity of agents. Usually, our minds are integrated — but we are also, in Farah’s words, “distinct and separable.”
Todd Feinberg makes a similar point when he speaks about the structure of the self. Normally, he says, we believe our selves are secure: “We maintain our ego boundaries.” But in some ways, he adds, “It’s an illusion — we’re much more fragile than we could care to believe.”
Dr. John R. Shea, Gr’84, is the editor of Penn Health, a magazine for the employees of the Penn Health System.