Book Review |
The philosopher of emerging clinical neurology
In the 1860s and 1870s, almost simultaneously in Paris and London, clinical neurology began to emerge as a special area of medical practice. The Parisian development occurred mainly at the Salpêtrière, ancient repository of a sizeable population of the hitherto often uncategorized chronically ill. There the dominant neurological interest was in clinical phenomenology and nosology. From the outset the predominant figure was Jean-Martin Charcot, subsequently occupant of the world's first chair of neurology. He became a popular and highly successful consultant and the influential founder of a school of talented neurologists. By virtue of his famous clinical demonstrations that were open to the public, and his flirtation with hysteria and hypnosis, he became known to a Parisian circle outside medicine. Throughout the first half of the 20th century his name was introduced to an even wider circle by his figuring in parts of Axel Munthe's extraordinary and widely read autobiography, The Story of San Michele (Munthe, 1929
).
The pattern of events in Britain was somewhat different. As in France, there had been occasional earlier figures who had made significant contributions to neurological knowledge, e.g. Thomas Willis, Marshall Hall, Robert Bentley Todd, but the beginnings of the progressive development of British clinical neurology were centred on a relatively small, newly opened, specialized institution, the Hospital for the Paralysed and Epileptic at Queen Square in London. There the emphasis came to be rather more experimental and interpretive than phenomenological. No immediately obvious early leading figure emerged, though Brown-Séquard might have been seen to fulfil that role had he remained longer on the institution's staff. More gradually, John Hughlings Jackson began to stand out from other notables such as Ramskill, Russell Reynolds, Sieveking, Radcliffe, Ferrier, Gowers, Bastian and Horsley as the predominant Queen Square figure. Jackson seems to have been a rather reclusive man whose very considerable achievements never received formal State acknowledgement. Apart from most medical students having heard of ‘Jacksonian epilepsy’, his achievements never became widely known outside his own special area of medicine. Jackson was not an experimenter in the usual sense of the word, but rather an extremely careful observer of disease phenomena. He then applied his formidable intellectual powers to interpret these ‘experiments on the brain made by disease’ to arrive at a reasonably comprehensive original interpretation of human nervous system function in health, and when diseased. In so doing, he provided emerging clinical neurology with much of its philosophical underpinning.
|
It is possible to see in Jackson's neurological thought the interplay of two chief concepts. The first was that the human nervous system had evolved as a sensori-motor reflex apparatus organized in a hierarchy of functional levels; higher levels modulated the function of lower levels, and disease in any one level diminished the function of that level and also released from its restraint the function of lower levels, thus producing negative or positive symptoms, respectively. The second concept was that localized representation of various aspects of brain function existed in certain parts of the nervous system, including the cerebral cortex.
Neither concept was entirely original. The idea that the brain functioned as a reflex mechanism went back to Descartes and Willis in the 17th century, and was developed further by Jackson's former teacher at York, Thomas Laycock, after Robert Whytt and then Marshall Hall had elucidated the mechanism of the reflex arc. Jackson's use of the concept of evolution seems to have come from the psychologist Herbert Spencer, with Jackson also employing the idea that disease undid the process of nervous system evolution (thus producing ‘dissolution’). Russell Reynolds (1861) had introduced the idea of positive and negative symptoms in neurological disease shortly before Jackson's day, without adequately explaining their mechanisms of production. As to localization of function, when Jackson began his work it was generally believed that the cerebral convolutions functioned in an overall fashion as the seat of the mind and will. However, there had been speculation, not only from the by then discredited phrenologists, that some localized representation of function must exist in the cerebrum. Then Paul Broca (1861) correlated loss of speech with demonstrated tissue destruction in a restricted part of the surface of the left cerebral hemisphere, thus providing the initial pathological evidence for localized representation of function in the cortex. Soon after, in 1870, Jackson published an analysis of ‘convulsions beginning unilaterally’ in which he recognized that not only speech but also movements were represented in the cortical territory of supply of the contralateral middle cerebral artery and in the underlying striatum. He also deduced that such convulsions originated in the cortex, and not in the medulla oblongata which at that time was generally considered the seat of epileptogenesis. Possibly such heretical ideas would have been ignored at the time, if not ridiculed, had not in that same year Fritsch and Hitzig published experimental animal stimulation data supporting Jackson's cortical localization of motor representation. Despite Jackson's priority in this matter, many subsequent writers have tended to give the chief credit for recognition of localization of function in the cortex to the experimental physiologists. Yet it seems to have been Jackson's human localization data, rather than the animal work, which guided intrepid surgeons such as Macewen, Godlee and Horsley when they began to carry out intracranial surgery before any ancillary investigations that could demonstrate the site of cerebral pathology were available to them.
|
Jackson did not attempt to locate the mind, or the will, in any particular part of the brain. Nor was his localization of individual aspects of brain function the point by point one that contemporary experimental physiologists were finding. Instead, he thought that each aspect of brain function was widely represented in the cerebral grey matter, though the representation of a particular aspect tended to be concentrated in a more restricted region which broadly corresponded to the physiologists’ experimentally determined location. In 1881 Jackson summed up his attitude to localization of function in stating ‘I am not what has been called a universaliser’ and, a paragraph later, ‘Nor am I a localizer’. Yet, by combining the idea of disease-produced dissolution of higher level brain function and its consequences with his concept of localization of function in the cerebrum, and particularly in the cortex, Jackson provided medicine with a tool for interpreting the functional consequences of brain disease, whatever its pathological basis.
Jackson envisaged a two and, later, a three level hierarchy of sensori-motor brain function. The lower of his original two levels was the motor region of the cortex, and the higher level was the pre-frontal region of the cerebral hemispheres. The third level he later added was the spinal cord and brainstem, with the motor cortex then becoming the intermediate level. Until after 1877, when Flechsig showed that the pyramidal tracts originated in the cortex and not in the striatum, Jackson seems to have also included the striatum in his intermediate level (Flechsig, 1877). He used his three hierarchal level concept to interpret convulsive epileptic seizures and chorea as positive phenomena due to removal of restraint from previously modulated intermediate level function, and hemiplegia as due to loss of function at the intermediate level.
Jackson reasoned that speech, as distinct from articulation, was represented in the cortex in the form of propositions rather than as individual words. Hence disease which damaged his highest functional nervous system level impaired propositional more than emotional speech. This interpretation proved uncongenial to the subsequent generation of aphasiologists who attempted to locate various aspects of speech in different but interconnected portions of the cerebral cortex. Later, Henry Head (1920), dissatisfied with the speech diagram-makers’ approach, resurrected Jackson's ideas.
Over the two decades following 1870, Jackson expanded his concept of the local cortical origin of focal motor epileptic seizures into a wide-ranging hypothesis that accounted for nearly all the then known types of epileptic event in terms of the effects of ‘discharging lesions’ in the cerebral cortex (the existence of the primary generalized epilepsies could not be known until electroencephalography came into use half a century later). Jackson was not the first to postulate that epilepsy arose in the cortex. Richard Bright had done that in 1831 (Bright, 1831), and by 1866 Jackson's friend Samuel Wilks had come to the same realization independently (Wilks, 1866). Between 1869 and 1874 Wilks’ junior colleague at Guy's Hospital, the short-lived John Thompson Dickson, developed the idea of cortical epileptogenesis, and a belief in the principle of localization of function in the cortex, into a comprehensive explanation of epileptogenesis reasonably similar to that which Jackson achieved some two decades later (Eadie, 2007). However, Jackson in 1870 was in advance of his contemporaries in that he specified the actual site in the cortex where he believed one variety of seizure activity originated. Over the years, he wrote again and again on the topic whilst the medical profession increasingly became convinced of the validity of his interpretation.
Those probably were Jackson's main original insights, though he also published other novel observations including an interpretation of the contribution of the cerebellum to motor control, and pioneered the use of the ophthalmoscope as a neurological diagnostic aid.
Most of Jackson's numerous papers were written in prose that is not particularly easy to follow. To some extent the difficulty lies in his extreme carefulness with language and in the unfamiliarity of the ideas he attempted to formulate. For instance, in 1888 in one of his many footnotes he found it desirable to explain that:
‘The expression "discharging lesion" is objected to by some of my medical friends. I have been told that we can understand an ulcer discharging, but not nerve cells.’Jackson tended to repeat the same idea at more than one place in the same paper, or in different papers, and each time clothed the concept in different words, presumably to make his meaning clearer. Unfortunately, this policy also sometimes leaves the reader uncertain whether there had been a subtle change in his thought. As well, some of Jackson's interpretations changed as time passed and new data became available, but he tended to let superseded concepts fade from view rather than openly abandon them. Unfortunately for posterity, he never drew all of his ideas together into a definitive statement of his final intellectual position.
It may seem curious that the first book devoted to so important a thinker as Jackson did not appear until 1998, more than 80 years after his death. Substantial biographies of other major, but on the whole ultimately less influential, neurological figures of Jackson's generation had appeared earlier, e.g. Broca in 1992, Brown-Séquard in 1945 and 1993, Charcot in 1959 and 1995, Gowers in 1949 and Horsley in 1918 and 1966. Several factors may account for this apparent biographical neglect of Jackson. His achievements had been acknowledged during the latter years of his life by events such as the founding of the triennial Hughlings Jackson lecture, and the earlier lecturers had dealt with the major individual aspects of his thought. Several of his obituaries had been reprinted in 1925 in the volume of his Neurological Fragments edited by James Taylor; his two volume Selected Writings, again edited by Taylor, had appeared in 1931 (Taylor, 1931), and in 1935 the international neurological community had celebrated the centenary of his birth. In accordance with his directions, Jackson's executors had burned all of his papers; he had been a childless widower for the latter half of his life and by the time of his death none of his near relatives lived in Britain. Jackson seems to have been basically a good, kindly and well-intentioned man with some mild and relatively harmless eccentricities who led a quiet, lonely existence mainly devoted to intellectual interests. His thought would have been difficult for a writer to translate into simple language that the majority of general readers could follow easily. All in all, he would not have been a particularly attractive subject for a biographer who aimed to reach more than a quite specialized readership.
By virtue of long personal contact and professional insight, Edward Farquhar Buzzard would probably have been the man best placed to be Jackson's biographer. Jackson had known him since he was a newborn baby, the oldest son of Jackson's neighbour, close friend and Queen Square colleague, Thomas Buzzard. Later Farquhar Buzzard became Jackson's house physician at Queen Square and subsequently his junior consultant colleague there, before Buzzard moved from neurology to the Regius Chair of Medicine at Oxford. In 1934 Buzzard wrote an intimate and moving account describing Jackson's social ineptitude and bumbling kindness, and his restlessness when his interest was not engaged, but unfortunately never went on to a full biography (Buzzard, 1934). It remained for the nonagenarian Macdonald Critchley, in collaboration with his wife Eileen, to produce a full biography of Jackson (reviewed in Brain 1999; 122: 1199–1200). Critchley was still a schoolboy when Jackson died in 1911, and his knowledge of Jackson was second-hand, obtained either from earlier written accounts or by word of mouth from Critchley's more senior colleagues at Queen Square and those at King's College Hospital (Aldren Turner and Kinnier Wilson). The Critchleys’ biography contains a considerable amount of genealogical detail that was not previously available, but much of its text comprises accounts of knowledge of the areas in which Jackson made his main contributions rather than critical assessments of Jackson's contributions themselves. The book provides relatively little information about Jackson's life and personality that is not available elsewhere. It seems unlikely that further significant unpublished material concerning Jackson will be discovered, unless it is buried in the papers of his contemporaries that may have been stored in various archives and not examined with an interest in Jackson as such. Hence the Critchleys’ book may well remain the definitive biography of John Hughlings Jackson.
However, more recently, just over a century after the November issue of this journal [Brain 1906; 29 (Part 3)] was dedicated to John Hughlings Jackson on the occasion of the 50th anniversary of his commencing medical practice, another book dealing with the man has appeared. This book, by two west coast American neurologists, George York and David Steinberg, both long interested in Jackson, provides an introduction to his life and thought, but mainly comprises a catalogue raisonné of his published work. The account of his life is a competent one which inevitably contains little new material. Some might quarrel with certain statements in the authors’ interpretation of Jackson's thinking, though when one is trying to interpret what were at their time of writing novel ideas expressed in cautious and sometimes convoluted language it is difficult to avoid personal attitudes and viewpoints influencing the interpretation. The authors tend to give Jackson credit for certain ideas which he had probably appropriated from others, either consciously or subconsciously, e.g. positive and negative symptoms in brain disease, the release of lower level function when a higher level was diseased (anticipated by Francis Anstie in relation to the effects of alcohol and other sedatives and by Thomson Dickson in relation to epileptogenesis). The main importance of the York–Steinberg book lies in its careful cataloguing of Jackson's publications, correcting errors in the list which appeared in the Neurological Fragments and in the second volume of the Selected Writings. As well, it added a further 84 publications by Jackson or written about him during his lifetime which had escaped previous notice. The catalogue constitutes a resource of great value for those interested in Jackson's ideas, and these ideas are likely to remain highly relevant to neurology for generations to come. Relatively easy access to Jackson's Selected Writings over a period of some 70 years has led to a degree of neglect of Jackson's papers that were not included in the two volumes. Now that the Writings are out of print and a more extensive and corrected list of Jackson's publications is available, and all the publications themselves are known to be accessible in various places, it would be of considerable service to those interested in the history and philosophy of neurology, and a further acknowledgement of the genius of John Hughlings Jackson, if the text of all of these publications, the complete writings of John Hughlings Jackson, could be made generally available, perhaps in electronic format.
Central Clinical School
University of Queensland, Royal Brisbane and Women's Hospital
Herston
Brisbane
Australia 4027
References
Bright R. Reports of medical cases selected with a view of illustrating the symptoms and cure of disease by a reference to morbid anatomy. (1831) v. II. London: Longman, Rees, Orme, Brown, Green and Highley.
Broca P. Nouvelle observation d’aphémie produite par une lésion de la moitié postérieure des deuxième et troisième circomvolutions frontales. (1861) s.2(6). Anatomique de Paris: Bulletin et Mémoires de la Societé. 398–407.
Buzzard EF. Hughlings Jackson and his influence on neurology. Lancet (1934) 224:909–13.[CrossRef]
Eadie MJ. The epileptology of John Thompson Dickson (1841-1874). Epilepsia (2007) 48:23–30.[Web of Science][Medline]
Flechsig PE. Uber ‘Systemkrankungen’ im Ruckenmark. Archiv Heilkungen (1877) 18:289–343.
Head H. Aphasia: an historical review. Brain (1920) 43:390–411.[CrossRef][Web of Science]
Jackson JH. A study of convulsions. Transactions of the St Andrews Medical Graduates Association. (1870) 3:162–204. Reprinted in Taylor J (1931) Selected writings of John Hughlings Jackson. Vol 1. London: Hodder and Stoughton. pp. 8–36.
Jackson JH. On some implications of dissolution of the nervous system. (1882) 2. Medical Press and Circular. 411–414. Reprinted in Taylor J (1931) Selected writings of John Hughlings Jackson. Vol. 2. London: Hodder and Stoughton; 1882. pp. 29–44.
Munthe A. The story of San Michele (1929) London: Murray.
Reynolds JR. Epilepsy: its symptoms, treatment, and relation to other chronic convulsive diseases (1861) London: Churchill.
Taylor J, ed. Selected writings of John Hughlings Jackson. (1931) Vols 1 and 2. London: Hodder and Stoughton.
Taylor J, ed. Neurological fragments by J Hughlings Jackson. (1925) London: Oxford University Press.
Wilks S. Observations on the pathology of some of the diseases of the nervous system. Guy's Hospital Reports (1866) 12:157–244.
CiteULike 
Connotea 
Del.icio.us What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||