PENFIELD, WILDER GRAVES

(b. Spokane, Washington, 26 January 1891; d. Montreal, Canada, 5 April 1976),

neurosurgery, neurology, epilepsy.

Penfield helped develop an important surgical treatment for epilepsy and used the results to investigate the functional organization of the brain. He was instrumental in founding, funding, and staffing the Montreal Neurological Institute (MNI) at McGill University, which he directed from 1934 to 1960. Penfield, according to his autobiography No Man Alone (1977), valued his fund-raising and administrative work at MNI, perhaps as much as his research and clinical practice. Penfield devotes more than a chapter of No Man Alone to an unprecedented and dangerous operation to relieve a patient’s debilitating epileptic seizures. Penfield says its success was important to him not only because he hoped it would open the way to new surgical treatments of epilepsies caused by circulatory defects, but also because the patient’s parents decided to make a generous financial contribution to MNI.

Wilder Graves Penfield was born in Spokane, Washington, in 1891, while Hughlings Jackson was treating and observing epileptics in London. Crucial components of Penfield’s research program were later to develop from Jackson’s clinical studies. At the time of Penfield’s death in 1976, technicians and statisticians were developing brain imaging techniques that would help neuroscientists pursue Penfield’s goal of mapping the functional geography of the brain.

Becoming a Surgeon Penfield’s father, Charles Samuel Penfield, was an unsuccessful, financially distressed physician. He abandoned the family when Penfield was eight. His mother, Jean (Jefferson) Penfield, moved him with his brother and sister to Hudson, Wisconsin, where they lived for some time with her father. She founded the Galahad School for Boys, where Penfield received his high school education. When he was thirteen a friend told his mother about the Rhodes Scholarship. “This …. is just the thing for you, Wide,” she said. He went to Princeton University because that seemed a good place to apply for a Rhodes. There he became interested in human physiology and chose medicine for a profession. He played football (Rhodes applicants were judged partly on athletic prowess). After graduation he coached to earn money while he waited for his Rhodes. He married Helen Kermott, and as World War I began, they left for Oxford University, where he studied clinical medicine with William Osler and neurology with Charles Sherrington. During a spring vacation the Germans torpedoed the ferry on which he was trying to cross the English Channel to volunteer at a Red Cross hospital. Osler invited Penfield to stay in his home while he recuperated from the injuries he sustained.

After Oxford, Penfield completed his MD at Johns Hopkins University. He interned under Harvey Cushing in Boston at Peter Brent Brigham Hospital. After his internship he practiced surgery for seven years at New York Presbyterian Hospital. During a leave he traveled to Spain to learn nerve cell staining techniques from Santiago Ramón y Cajal and Pio del Rio-Hortega. Penfield also went to Germany, where he watched Ottfrid Foerster employ surgical techniques he would use later to treat his own patients. He also investigated microscopic details of brain healing and scarring in tissue samples that Foerster provided.

Clinical Research and the MNI Penfield became convinced that the best way to investigate the brain would be for clinicians, neurologists, anatomists, pathologists, and psychologists to collaborate. He left New York for Montreal in 1928, hoping to practice surgery in an environment that fostered interdisciplinary brain research. His

efforts made it possible for MNI to open six years later; it continues to be a leading center for neurological research and the treatment of brain diseases. In 1954 Penfield and Herbert Jasper published Epilepsy and the Functional Anatomy of the Human Brain, an exemplary product of the interdisciplinary research that MNI was designed to facilitate. It contains Penfield’s most influential contributions to the surgical treatment of epilepsy, along with discussions of what he and his multidisciplinary collaborators learned about the brain from 750 patients Penfield treated between 1928 and 1953.

In 1874 the servant of a surgeon named Barthalow had an accident that left a hole in her skull. Although she was conscious, Barthalow found he could manipulate the top of her brain without causing her additional pain. (The brain contains no pain sensors.) Mechanical irritation had no effect, but weak electrical stimulation caused muscle contractions. Strong shocks caused convulsions, followed by coma. Some years before Penfield’s internship, Harvey Cushing had elicited sensations in a patient by introducing a weak electric current behind the Rolandic fissure. In the operations Penfield observed in Germany, Foerster stimulated different points on the surface of a conscious patient’s brain and used the resulting motor and verbal responses as clues to the location of tissues he could ablate to prevent or relieve their seizures. Like Cushing, he applied local anesthetics to the scalp and the inner lining of the skull to keep the patient relatively comfortable without general anesthetic. Penfield realized that, besides helping patients, this technique could provide valuable data for neurologists, physiologists, and anatomists. He left for Montreal looking forward to “operating, under local anesthesia, on a long series of patients.” During his career he performed 1,132 such operations and used the results to investigate the following four issues. The first two are clinical. The third has to do with functional anatomy. The last is philosophical.

1. Locating Seizure Sources Many epileptic seizures begin with abnormal activity in a relatively small brain region. Motor and cognitive functions are disrupted as this activity spreads to other parts of the brain. Before it does so, it may produce distinctive motor symptoms (e.g., weakness or twitching) or experiential states called auras. If the fits are severe enough to warrant the risk, and if they cannot be controlled with drugs, the surgeon may treat the patient by destroying the brain region where the seizures begin. To this end, Penfield and his colleagues adapted Foerster’s techniques to develop what came to be called the Montreal procedure. The surgeon peels back flaps of skull and brain covering, passes an electrical current into one cortical bulge and crevasse after another, placing small numbered squares of paper on locations whose stimulation produces interesting results. The clinically significant tissue is in and near places where stimulation causes responses that mimic the aura or the motor activities that signal the start of a fit. Recording electrodes can also be inserted to detect abnormal electrical effects. The surgeon then destroys brain tissue judged to be responsible for seizures on the basis of the electrical recordings, responses to stimulation, and other evidence, including preoperative electroencephalograms (EEGs).

Although this technique benefited many patients, Penfield once said that brain surgery was such a terrible profession that he would hate it if he did not think it would change during his lifetime. A case in point was his removal of a great deal of frontal lobe tissue in a futile attempt to cure his older sister. She had been epileptic for so long that Penfield could remember being frightened by her seizures as a child. The surgery revealed an untreatable tumor that eventually killed her.

2. Locating Tissue the Surgeon Must Spare To avoid doing more harm than good, surgeons must spare brain regions whose destruction would cause unacceptably severe deficits. Some psychological functions required for acceptably decent quality of life depend upon structures whose location varies from brain to brain. For example, right hemisphere lesions impair speech in some patients, but not in many others. Penfield and his colleagues exploited the fact that cortical regions do not function normally under weak electrical stimulation to locate brain regions they should spare. To find speech areas, they stimulated various cortical regions while the patient performed naming and other simple language tasks. For example, when he was shown a picture of a foot, one patiently easily produced the word foot until a current was passed into the left side of his brain. As long as the stimulation continued, his best effort on the naming task was to say “that is what you put in your shoes.” Such results, together with his successful performances during right brain stimulation, indicated that his speech areas were in the left rather than the right hemisphere. By contrast, left brain tissue could be ablated in patients whose linguistic performance was impaired by right hemisphere stimulation only.

3. Localizing Brain Functions Penfield studied the effects of stimulation and surgical ablation to learn about the functional anatomy of the brain. In doing so, he said he was applying to humans the techniques of stimulating and surgically destroying small brain regions that Sherrington had used to study the organization of the primate nervous system. When Sherrington was in his nineties, he remarked to

Penfield that it must be great fun to speak to an experimental preparation and have it answer you. The ability of a conscious patient to describe what he or she experienced during surgery enabled Penfield to study psychological responses that Sherrington’s simian subjects could not reveal.

First-year neural anatomy students are familiar with one of the fruits of this research—the homuncular diagrams drawn by a Mrs. Cantlie. Penfield published the original diagram in 1937 and a revised version in 1950. Mrs. Cantlie’s homunculi are grotesquely distorted outlines of a body superimposed on a sketch of the top of the brain. They depict regions on either side of the Rolandic fissure whose stimulation produces sensory or motor effects. The shapes’ relative sizes, and relative positions of the homunculus’s head, hand, foot, and so on, indicate the relative sizes of the brain regions whose stimulation influenced the corresponding parts of the body. Thus, the homuncular hands are much larger than the homuncular chest because the regions where stimulation produces responses in the former are much larger than those whose stimulation produces responses in the latter. Homuncular genitals are drawn next to homuncular feet to indicate the relative positions of their cortical regions.

The best-known result of Penfield’s stimulation studies was his discovery that temporal lobe stimulation could produce vivid experiential effects. Some patients reported experiencing things they had experienced in the past. One said he saw a 7-Up bottling company, and then a bakery he had seen years before. Another heard the theme song of a radio program he used to listen to. Another heard an orchestra playing “Marching along Together.” When Penfield ran a weak current into a boy’s frontal lobe he said he could hear his mother telling his brother he had his coat on wrong. Stimulation a short distance away elicited the experience of listening to his mother talking on the phone to an aunt. In some cases. Penfield obtained independent evidence that the electrically induced sights and sounds were very similar to experiences from the patient’s past. He concluded that in such cases the stimulation activated memory records through a process that differed from normal recollection.

In other cases, electrical stimulation evoked simple hallucinatory experiences of flashes of light, colored triangles, banging noises, noxious smells, the feeling of something stroking the back of the hand, and so forth. Some electrical stimulations altered the patient’s experience of what was actually happening, producing feelings of strangeness, loneliness, fear, déjà vu, and so on. Penfield argued that such results could bring sensation, perception, memory, emotion, one’s interpretation of one’s own ongoing experience, along with other “psychical phenomena …. into the field of physiology.” (An online video of Penfield at work stimulating patients’ brains and interviewing the woman who heard “Marching along Together” is available from http://www.virtualmuseum.ca/Exhibitions/Medicentre/en/penf_video.htm.)

Penfield originally thought memory records of past experiences were stored in the cortex. But the evidence he accumulated between 1950 and 1958 inclined him to a more complicated theory. He knew that during electrically induced auditory or visual experiences the patient cannot hear or see normally. During electrically induced motor activity, the patient cannot voluntarily control the affected body part. Penfield concluded that electrical stimulation disables the region into which the current passes at the same time that it produces an experiential or motor effect. If a bit of cortical tissue is disabled by electrical stimulation, it is plausible that it contributes to the production of a motor or sensory response by transmitting electrical impulses to brain regions that can still function normally enough to produce it.

Penfield decided that cortical stimulation produces its effects via impulses that travel from the cortex to sub-cortical ganglia too far from the stimulating current to be disabled. By analogy, if cortical stimulation activates memory records, those records must be stored below rather than in the cortex. The profusion of nerve fibers that connect the cortex to subcortical ganglia in and near the top of the brain stem suggests that nerve signals can easily pass back and forth between these regions. Furthermore, it was well-known that memory deficits result from hippocampal lesions. Penfield proposed (in his last scientific book, The Mystery of the Mind, 1975) that the hippocampi contain “keys-of-access” to records of past experiences. In an early work, he had characterized memory records as pathways “of synaptic and ganglionic facilitations which linger on after present experience is passed.” Accordingly, he concluded that cortical stimulation can make a patient relive an old experience by initiating a current that turns the key to the pathway which constitutes its memory record.

Penfield told roughly the same story about other responses to brain stimulation. The keys to pathways whose activation produces different sensory and motor effects occupy different positions in and around the top of the brain stem. When different cortical regions are stimulated, they transmit electrical impulses to different keys. Which effect is produced depends upon which ganglionic pathway is opened by the key that the current reaches. Furthermore, when a given cortical region is disabled temporarily by stimulation or permanently by ablation, the brain loses its normal access to one or more subcortical pathways. That would explain, for example, why patients cannot voluntarily lift an arm while it moves in response to brain stimulation, pronounce words correctly during stimulation that elicits vocal responses, and why stimulation effects involving memory do not mimic normal recollection.

Penfield and Jasper argued for the existence of what they called a “centrencephalic system” consisting of structures that receive and integrate inputs from opposite sides of the brain. Without such a system, the fact that visual stimuli for objects on opposite sides of the nose do not register on the same side of the brain would prevent us from experiencing the visual field as a single, well-unified whole. Without such a system, electrical activity in one hemisphere could not initiate motor activity in response to commands whose understanding depends on activity in the other hemisphere. In general, both reflex and purposeful responses to environmental stimuli would seem to depend upon the integration of inputs from anatomically discrete brain regions. Penfield tentatively proposed that centrencephalic integration is accomplished in the region in and around the top of the brain stem where he had located the keys to memory, motor, and sensory pathways. (For reasons he did not explain, Penfield ignored the corpus callosum—a massive bundle of nerve fibers that run between the hemispheres.)

Penfield made significant, if controversial, contributions to long-standing disputes over locationism. Location-ists follow Franz Gall in supposing that each basic sensory, motor, or other psychological function is uniquely supported by its own anatomically discrete brain structure. Antilocationists, such as Marie-Jean-Pierre Flourens and Karl Lashley, believe that some important functions can be supported equally well by different parcels of brain tissue. Penfield’s findings favored the locationists with regard to relatively simple motor and sensory functions. For example, motor regions whose stimulation elicits movements in the fingers of the left hand stand in the same positions relative to one another and to the Rolandic fissure on the right side of every normal brain, even though their sizes and the distances between them vary.

Things are not so clear with regard to more complicated functions. For example, the standard aphasia literature purports to identify a fairly large number of sharply distinguishable language deficits, each of which results from damage to a different anatomical structure. In right-handed subjects, damage to Broca’s area in the left hemisphere is said to cause a distinctive inability to produce words, while damage to Wernicke’s area is supposed to cause an independent and very different deficit involving an inability to understand words. Damage to counterpart regions in the right brain is said produce the same deficits in left-handers. Locationists think that Broca’s and Wernicke’s areas operate more or less independently to support different language functions.

In their 1959 Speech and Brain Mechanisms, Penfield and Roberts reviewed 569 of their case histories, together with some others reported in the standard literature. They concluded, contrary to received doctrine, that “the left hemisphere is usually dominant for speech, regardless of handedness” but that it is not dominant for speech in every right-handed subject. Only 46 of 52 right-handers exhibited symptoms of Broca’s aphasia during left hemisphere stimulation near Broca’s area. Five left-handed patients did not exhibit language difficulties during right hemisphere stimulation near Broca’s area. The literature included one (controversial) report of surgical destruction of Broca’s area that did not produce permanent symptoms of Broca’s aphasia.

Another remarkable finding was that although language task performances were impaired by stimulation within a relatively large parieto-temporal region and a smaller frontal region, no more than half of Penfield’s patients exhibited the same (or any) temporary deficits during the stimulation at exactly the same location in either region. Penfield and Roberts could say the posterior tempero-parietal region and Broca’s area were the first and second most important areas for speech. A locationist might find that congenial in spite of the anatomical variations among different brains. But Penfield and Roberts rejected the locationist idea that language and other basic functions are executed by relatively small, anatomically discrete brain structures functioning in relative independence from one another. Believing as they did that these functions involve activities on both sides of the brain, the locations they proposed were complex networks of cortical and subcortical structures with many anatomical and physiological interconnections.

In this way, Penfield could square his locationist sympathies with another finding. Contrary to the locationist picture of sharply distinguishable, mutually independent language functions, Penfield found that surgical interventions typically did not produce pure examples of the allegedly independent language deficits that the locationists described. Instead, simulating or ablating a single cortical region produced combinations of symptoms of varying severity associated with a number (in some cases, a large number) of different language deficits. This was in keeping with Jackson’s idea that motor and sensory functions are carried out by hierarchically arranged networks of interconnected structures in various places between the top of the spinal cord and the outer surface of the brain. But Penfield allows for more extensive and different kinds of anatomical variation over different brains than Jackson recognized.

4. Mind and Brain What do brain and mental functions have to do with one another? Although he considered this a philosophical question, Penfield thought putative answers should be tested against anatomical, physiological, and clinical evidence. Following Sherrington, he assumed that unless our mental lives can be satisfactorily explained just by appeal to brain functions, we must think that mind and brain are different entities that interact somehow.

Penfield characterized consciousness as the mental state that distinguishes wakefulness from dreamless sleep, and normal self-aware purposeful activity from the aimless, stereotypical, perseverative behavior of epileptics who have lost both awareness of and control over what they are doing, and who cannot adjust their behavior to what goes on around them. Consciousness and the ability to plan and direct behavior and to adjust it to changing circumstances vanish when a seizure spreads to the top of the brain stem and neighboring structures. It returns when this mechanism resumes its normal functions. It follows that consciousness depends upon the centrencephalic system.

But are the functions of this or any other part of the brain sufficient for conscious mental activity? Penfield says he cannot prove they are not sufficient, but that the available evidence provides no good reason to think they are. He was struck by his inability to stimulate the cortex to make patients think that they were responsible for the movements his manipulations evoked. Nor could he make patients think the things they experienced during brain stimulations were actually happening. Accordingly, he thought, if the centrencephalic system is fully active during cortical stimulation, it is plausible that it cannot account for consciousness. That is why Penfield thought his research had produced “no good evidence that the brain alone can carry out the work the mind does.” But he warns us not to “pretend to draw a final scientific conclusion” about whether mind and brain are separate entities until the energy that the mind uses to act on the brain is discovered (as he expected would happen eventually).

Later Life Penfield retired from the McGill medical faculty in 1954, and gave up his directorship of MNI six years later. During his retirement he continued his application of clinical findings to questions about mind and brain, delivering the lectures incorporated into Speech and Brain Mechanisms in 1956, and completing the final draft of Mystery of the Mind two years before he died. And there were other interests. Before his mother died, Penfield promised to complete a novel she had been writing based on the biblical story of Sarah. He rewrote the book and published it under the title No Other Gods. In addition to traveling and lecturing in Russia, China, and India, he also found time to publish The Torch, a novel about Hippocrates; The Difficult Art of Giving, a tribute to the Rockefeller Foundation administrator who helped fund the MNI; and The Second Career, a collection of essays on education and other topics. He completed his autobiography the year he died of stomach cancer in Montreal, survived by two daughters—Priscilla and Ruth Mary—two sons, Wilder Jr. and Amos Jefferson, and many grandchildren.

BIBLIOGRAPHY

WORKS BY PENFIELD

Editor. Cytology and Cellular Pathology of the Nervous System.New York: Paul B. Hoeber, 1932.

With J. Evans. “The Frontal Lobe in Man: A Clinical Study of Maximum Removals.” Brain 58 (1935): 115–138.

With E. Boldery. “Somatic, Motor, and Sensory Representation in the Cerebral Cortex of Man as Studied by Electrical Stimulation.” Brain 60 (1937): 389–443.

“Epileptic Automatism and the Centrencephalic Integrating System.” Association for Research in Nervous and Mental Disorders 30 (1950): 513–538.

With Theodore B. Rasmussen. The Cerebral Cortex of Man. New York: Macmillan, 1950.

With Kristian Kristiansen. Epileptic Seizure Patterns. Springfield, IL: Charles Thomas, 1951.

No Other Gods. Boston: Little Brown, 1954.

With Herbert Jasper. Epilepsy and the Functional Anatomy of the Human Brain. Boston: Little Brown, 1954

“The Permanent Record of the Stream of Consciousness.” Proceedings XIV International Congress on Psychology: Acta Psychologica 11 (1955): 47–69.

The Excitable Cortex in Conscious Man. Fifth Sherrington Lecture. Liverpool, U.K.: University of Liverpool Press, 1958.

With Lamar Roberts. Speech and Brain Mechanisms. Princeton, NJ: Princeton University Press, 1959.

The Torch. Boston: Little Brown, 1960.

The Mystery of the Mind: A Critical Study of Consciousness and the Human Brain. Princeton, NJ: Princeton University Press, 1975.

No Man Alone: A Neurosurgeon’s Life. Boston: Little Brown, 1977. Penfield’s autobiography.

With Phanor Perot. “The Brain’s Record of Auditory and Visual Experiences: A Final Summary and Discussion.” Brain 86 (1963): 595–696.

The Second Career with Other Essays and Addresses. Boston: Little Brown, 1963.

The Difficult Art of Giving: The Epic of Alan Gregg. Boston: Little Brown, 1967.

OTHER SOURCES

Feindel, William, and Richard Leblanc. “History of the Surgical Treatment of Epilepsy.” In A History of Neurosurgery, in Its Scientific and Professional Contexts, edited by Samuel H. Greenblatt, T. Forcht Dagi, and Mel Epstein, 465–488. Park Ridge, IL: American Association of Neurological Surgeons, 1997.

Rasmussen, Theodore. “Wilder Penfield, 1891–1976.” Journal of Neurosurgery 45, no. 3 (1976): 248–250.

Ruelland, J. G. “Wilder G. Penfield (1891–1976), Neurosurgeon and Scientist.” Versalius: Acta Internationales Historiae Medicinae 11, no. 2 (December 2005): 64–69.

Jim Bogen

Wilder Graves Penfield

1891-1976
American-born Canadian neurosurgeon who diagnosed the cause of epilepsy and perfected a surgical cure.

Wilder Graves Penfield was born in Spokane, Washington, on January 26, 1891. He was one of three children born to Charles Samuel and Jean (Jefferson) Penfield. His father was a physician and died when Penfield was very young. To support herself and her family , Penfield's mother became a writer and Bible teacher. Penfield spent his early years at the Galahad School in Hudson, Wisconsin, where his mother worked as a housekeeper.

Upon graduation in 1909, Penfield was accepted at Princeton University. He was active in extra-curricular activities and became president of his class. He was so good at football, that upon graduation in 1913, he was hired as a coach. After graduation from Princeton with a degree in literature, Penfield held a Rhodes scholarship and a Beit Memorial Research fellowship at Oxford University, where he studied with Sir William Osler and Sir Charles Scott Sherrington. He married Helen Katherine Kermott in 1917 and eventually raised four children. Penfield received his medical degree from Johns Hopkins University in Baltimore in 1918. He worked in Sherrington's research laboratory at Oxford from 1919 to 1921.

Penfield returned to the United States in 1918 to receive training in general surgery and neurosurgery in New York City. In 1924 he founded the Laboratory of Neurocytology at Presbyterian Hospital, Columbia University, and worked there as associate attending surgeon from 1921 to 1928. In 1928 he was appointed neurosurgeon to the Royal Victoria Hospital and the Montreal General Hospital. It was here that he perfected his surgical operation for severe epilepsy . He had learned, perfected, and adapted the many techniques used in this operation from visits to Europe he had made while at Montreal.

The results of one of these operations in 1931 gave Penfield the idea to write a general textbook regarding neurosurgery. Instead of writing it all himself, he decided to ask other specialists in this field to contribute to the book. The resulting book, Cytology and Cellular Pathology of the Nervous System (1932), turned into a three volume discussion of neurology. The collaboration that had produced the book gave Penfield the idea to create an institute furthered by the same cooperative techniques. He established the Montreal Neurological Institute on this idea and became its first director in 1934, holding this post until 1960. He was a professor of neurology and neurosurgery at McGill University from 1933 to 1954.

Penfield became a naturalized Canadian citizen in 1934 and served as a colonel in the Royal Canadian Army Medical Corps from 1945 to 1946. He headed many wartime projects including investigating motion sickness, decompression sickness, and air transportation of persons with head injuries. Penfield's wartime experiences supplied two books; Manual of Military Neurosurgery (1941) and Epilepsy and Cerebral Localization (1941).

After the war he continued his studies on epilepsy by undertaking a study of the removal of brain scars resulting from birth injuries. He was a fellow of the Royal Society of London and of the Royal Society of Canada and received the Order of Merit from Queen Elizabeth (1953). He also received numerous scientific awards and lectureships. He helped found the Vanier Institute of the Family and served as its first president (1965-1968).

After his retirement from the Montreal Neurological Institute in 1960, Penfield set out on what he called his "second career" of writing and lecturing around the world. Not one to take to retirement easily, Penfield said "…rest is not what the brain needs. Rest destroys the brain." He traveled abroad many times during this period and even lectured in China and Russia.

Penfield published The Difficult Art of Giving, The Epic of Alan Gregg (1967), a biography of the Rockefeller Foundation and the director who had approved the $1.2 million grant for the founding of the Montreal Neurological Institute, during this period. Second Thoughts; Science, the Arts and the Spirit (1970) and The Mystery of the Mind: A Critical Study of Conscience and the Human Brain (1975) were also published as he lectured around the world. Penfield finished his final work, the autobiographical No Man Alone: A Surgeons Story, just three weeks before his death from abdominal cancer in Montreal's Royal Victoria Hospital on April 5, 1976. This work was published posthumously in 1977 and was a fitting tribute to a man who was remembered by his friends and colleagues as one who always thought of his discoveries as just "exciting beginnings."

Medical research

Penfield chose epilepsy as his special interest and approached the study of brain function through an intensive study of people suffering from this condition. In choosing this approach, he was influenced by Sherrington and by John Hughlings Jackson, a British neurologist who viewed epilepsy as "an experiment of nature," which may reveal the functional organization of the human brain. To this study Penfield brought the modern techniques of neurosurgery—which allow the surgeon to study the exposed brain of the conscious patient under local anesthesia—while using electrical methods for stimulating and recording from the cortex and from deeper structures. The patient is able to cooperate fully in describing the results of cortical stimulation. By this surgical method it is possible in some patients to localize and remove a brain lesion responsible for epileptic attacks. Penfield used this approach primarily for the treatment of focal epilepsy. His pioneer work yielded impressive results, and his techniques for the surgical treatment of epilepsy became standard procedure in neurosurgery.

Writings and theories

Penfield's The Cerebral Cortex of Man (1950) summarizes the results of mapping the principal motor and sensory areas of the cortex, including the delineation of a new "supplementary motor area" and a "second sensory area." The results of temporal lobe stimulation are described in Epilepsy and the Functional Anatomy of the Human Brain (1954), and his remarkable observations on temporal lobe epilepsy are also recorded there. Penfield also defined four areas of the cortex concerned with human speech function and described them in Speech and Brain-Mechanisms.

Penfield was convinced that the brain of man—including all cortical areas—is controlled and "organized" through a group of subcortical centers. These centers lie within the upper brainstem and include the thalamus . For this functionally important area he coined the term "centrencephalon," and his view may be described as a "centrencephalic" theory of cerebral organization. In his view consciousness , self-awareness, depends upon the integrating action of this subcortical system, which in some way, as yet unknown, unites the brain into a single functioning organ. There is much evidence for such a theory, and Penfield developed it in his Sherrington Lectures, The Excitable Cortex in Conscious Man (1958).

Further Reading

Current Biography Yearbook. New York: H.W. Wilson Co., 1968. Current Biography Yearbook. New York: H.W. Wilson Co., 1976.

Fulton, John F. and Leonard G. Wilson, eds. Selected readings in the history of physiology. 1930. 2nd ed. 1966.

Granit, Ragnar. Charles Scott Sherrington: an appraisal. 1967.

Obituary. New York Times. April 6, 1976.

Penfield, Wilder Graves. No man alone: a surgeon's story. 1977.

Penfield, Wilder Graves. McGraw-Hill modern men of science. 1966.

Wilder Graves Penfield

The American-born Canadian neurosurgeon, Wilder Graves Penfield (1891-1976), founded and was the first director of the Montreal Neurological Institute. He diagnosed the cause of epilepsy and perfected a surgical cure.

Wilder Graves Penfield was born in Spokane, Washington, on January 26, 1891. He was one of three children born to Charles Samuel and Jean (Jefferson) Penfield. His father was a physician and died when Penfield was very young. To support herself and her family, Penfield's mother became a writer and Bible teacher. Penfield spent his early years at the Galahad School in Hudson, Wisconsin, where his mother worked as a housekeeper.

Upon graduation in 1909, Penfield was accepted at Princeton University. He was active in extra-curricular activities and became president of his class. He was so good at football, that upon graduation in 1913, he was hired as a coach. After graduation from Princeton with a degree in literature, Penfield held a Rhodes scholarship and a Beit Memorial Research fellowship at Oxford University, where he studied with Sir William Osler and Sir Charles Scott Sherrington. He married Helen Katherine Kermott in 1917 and eventually raised four children. Penfield received his medical degree from Johns Hopkins University in Baltimore in 1918. He worked in Sherrington's research laboratory at Oxford from 1919 to 1921.

Penfield returned to the US in 1918 to receive training in general surgery and neurosurgery in New York City. In 1924 he founded the Laboratory of Neurocytology at Presbyterian Hospital, Columbia University, and worked there as associate attending surgeon from 1921 to 1928. In 1928 he was appointed neurosurgeon to the Royal Victoria Hospital and the Montreal General Hospital. It was here that he perfected his surgical operation for severe epilepsy. He had learned, perfected, and adapted the many techniques used in this operation from visits to Europe he had made while at Montreal.

The results of one of these operations in 1931 gave Penfield the idea to write a general textbook regarding neurosurgery. Instead of writing it all himself, he decided to ask other specialists in this field to contribute to the book. The resulting book, Cytology and Cellular Pathology of the Nervous System (1932), turned into a three volume discussion of neurology. The collaboration that had produced the book gave Penfield the idea to create an institute furthered by the same cooperative techniques. He established the Montreal Neurological Institute on this idea and became its first director in 1934, holding this post until 1960. He was a professor of neurology and neurosurgery at McGill University from 1933 to 1954.

Penfield became a naturalized Canadian citizen in 1934 and served as a colonel in the Royal Canadian Army Medical Corps from 1945 to 1946. He headed many wartime projects including investigating motion sickness, decompression sickness, and air transportation of persons with head injuries. Penfield's wartime experiences supplied two books; Manual of Military Neurosurgery (1941) and Epilepsy and Cerebral Localization (1941).

After the war he continued his studies on epilepsy by undertaking a study of the removal of brain scars resulting from birth injuries. He was a fellow of the Royal Society of London and of the Royal Society of Canada and received the Order of Merit from Queen Elizabeth (1953). He also received numerous scientific awards and lectureships. He helped found the Vanier Institute of the Family and served as its first president (1965-1968).

After his retirement from the Montreal Neurological Institute in 1960, Penfield set out on what he called his "second career" of writing and lecturing around the world. Not one to take to retirement easily, Penfield said " … rest is not what the brain needs. Rest destroys the brain." He traveled abroad many times during this period and even lectured in China and Russia.

Penfield published The Difficult Art of Giving, The Epic of Alan Gregg (1967), a biography of the Rockefeller Foundation and the director who had approved the $1.2 million grant for the founding of the Montreal Neurological Institute, during this period. Second Thoughts; Science, the Arts and the Spirit (1970) and The Mystery of the Mind: A Critical Study of Conscience and the Human Brain (1975) were also published as he lectured around the world. Penfield finished his final work, the autobiographical No Man Alone: A Surgeons Story, just three weeks before his death from abdominal cancer in Montreal's Royal Victoria Hospital on April 5, 1976. This work was published posthumously in 1977 and was a fitting tribute to a man who was remembered by his friends and colleagues as one who always thought of his discoveries as just "exciting beginnings."

Medical Research

Penfield chose epilepsy as his special interest and approached the study of brain function through an intensive study of people suffering from this condition. In choosing this approach, he was influenced by Sherrington and by John Hughlings Jackson, a British neurologist who viewed epilepsy as "an experiment of nature, " which may reveal the functional organization of the human brain. To this study Penfield brought the modern techniques of neurosurgery—which allow the surgeon to study the exposed brain of the conscious patient under local anesthesia—while using electrical methods for stimulating and recording from the cortex and from deeper structures. The patient is able to cooperate fully in describing the results of cortical stimulation. By this surgical method it is possible in some patients to localize and remove a brain lesion responsible for epileptic attacks. Penfield used this approach primarily for the treatment of focal epilepsy. His pioneer work yielded impressive results, and his techniques for the surgical treatment of epilepsy became standard procedure in neurosurgery.

Writings and Theories

Penfield's The Cerebral Cortex of Man (1950) summarizes the results of mapping the principal motor and sensory areas of the cortex, including the delineation of a new "supplementary motor area" and a "second sensory area." The results of temporal lobe stimulation are described in Epilepsy and the Functional Anatomy of the Human Brain (1954), and his remarkable observations on temporal lobe epilepsy are also recorded there. Penfield also defined four areas of the cortex concerned with human speech function and described them in Speech and Brain-Mechanisms.

Penfield was convinced that the brain of man—including all cortical areas—is controlled and "organized" through a group of subcortical centers. These centers lie within the upper brainstem and include the thalamus. For this functionally important area he coined the term "centrencephalon, " and his view may be described as a "centrencephalic" theory of cerebral organization. In his view consciousness, self-awareness, depends upon the integrating action of this subcortical system, which in some way, as yet unknown, unites the brain into a single functioning organ. There is much evidence for such a theory, and Penfield developed it in his Sherrington Lectures, The Excitable Cortex in Conscious Man (1958).

Further Reading

The best biographical information on Penfield is his own No Man Alone: A Surgeon's Story (1977). There is an autobiographical sketch by Penfield in McGraw-Hill Modern Men of Science (1966). Also helpful are John F. Fulton and Leonard G. Wilson, eds., Selected Readings in the History of Physiology (1930; 2d ed. 1966), Ragnar Granit, Charles Scott Sherrington: An Appraisal (1967) and Current Biography (1968). A short obituary of Penfield appears in Current Biography (1976). A much longer obituary appears in the New York Times (April 6, 1976). □

Wilder Graves Penfield

1891-1976

American-born Canadian neurosurgeon who is best known for his contributions to the area of neurology. He founded the world-renowned Montreal Neurological Institute to research and further the knowledge of the human brain. Penfield was the first researcher to systematically map the brain by observing conscious patients' responses to electrical stimulation in specific areas of the brain. Through his research, he developed surgical procedures for treating debilitating neurological diseases such as epilepsy.