John Hughlings Jackson

Summary

John Hughlings Jackson (1835-1911) was an English neurologist who transformed the scientific understanding of epilepsy and laid the foundations of modern cortical localization. Working at the London Hospital and the National Hospital for the Paralysed and Epileptic, he proposed that seizures were the product of sudden excessive discharge from unstable grey matter in the brain, a formulation that replaced centuries of humoral and reflex-based theories. He organized the nervous system into three hierarchical levels borrowed from Herbert Spencer’s evolutionary philosophy, and described “dissolution” as the reversal of neurological development during disease. His clinical observation of the spreading march of localized convulsions gave his name to a distinct seizure type and helped secure the case for cortical motor localization a full decade before it was experimentally confirmed.

Background and Formation

Jackson entered neurology at a moment when the field lacked agreed-upon foundations. As Temkin’s survey of the period makes clear, the neurological situation around 1860 was defined more by negatives than positives: Franz Joseph Gall’s faculty localization was widely discredited, Flourens had established that the cerebral hemispheres were not electrically irritable, the course of the pyramidal motor tract had not yet been described, and the neuron theory lay still in the future.(Temkin, Owsei, 1971) The dominant explanation for epilepsy was Marshall Hall’s reflex theory, which attributed seizures to excitation of the medulla oblongata by peripheral nervous irritation, usually from the gastrointestinal tract.(Temkin, Owsei, 1971) Schroeder van der Kolk had gone further in 1859, locating the seat of epilepsy in the ganglionic cells of the medulla and comparing their discharge to an electric battery that fires and then requires time to recharge, an analogy that explicitly anticipated the vocabulary Jackson would later make canonical.(Temkin, Owsei, 1971)

The nosological debate defined the conceptual space that Jackson’s work would transform.(Temkin, Owsei, 1971) Both Sieveking and Reynolds converged on excluding localized convulsions with preserved consciousness from the category of epilepsy.(Temkin, Owsei, 1971) That exclusion was why Jackson called such attacks “epileptiform” rather than epileptic.(Temkin, Owsei, 1971)

Jackson trained in York and then at the London Hospital, where close clinical observation of hemiplegic and aphasic patients gave him the material his theories required. He worked within the tradition of careful post-mortem correlation that Richard Bright had practiced at Guy’s Hospital in the 1830s; Bright had already observed preserved consciousness during unilateral seizures and connected those seizures with lesions on the contralateral hemisphere.(Temkin, Owsei, 1971) What Jackson brought was not new clinical phenomena but, as Temkin emphasizes, a new mode of investigation: a method of correlating bedside observation with anatomical and physiological principles that proved more enduring than that of any contemporary.(Temkin, Owsei, 1971)

Epilepsy and the Concept of Discharge

Jackson’s first paper on epilepsy appeared in 1861 and concerned cases of epilepsy associated with syphilis, focusing on unilateral convulsions.(Temkin, Owsei, 1971) By 1863, he had confirmed by autopsy that unilateral epilepsy was caused by “obvious organic disease on the side of the brain, opposite to the side of the body convulsed, frequently on the surface of the hemisphere,” establishing the cortical localization basis.(Temkin, Owsei, 1971)

From this clinical foundation he developed the concept that became his most durable contribution: the distinction between “discharging lesions” and “destroying lesions.”(Temkin, Owsei, 1971) Where a cortical area was destroyed, the muscles it supplied were paralyzed; where it was damaged so as to become pathologically unstable, it would fire in disordered and excessive ways, producing convulsive movement. The grey matter was not absent or dead but hyperexcitable. After the discharge it would be exhausted, explaining the temporary paralysis (now called Todd’s paralysis) that followed some focal seizures.

This conceptual framework culminated in the formal definition published in the 1870 Study on Convulsions and elaborated in the 1873 paper on epilepsy: “Epilepsy is the name for occasional, sudden, excessive, rapid and local discharges of grey matter.”(Temkin, Owsei, 1971) The definition was deliberately broad. By reducing epilepsy to a physiological process rather than a disease entity, it implied, as Jackson frequently stated, that “there are only epilepsies.” Sneezing was, in Jackson’s phrase, “a sort of healthy epilepsy.” He even proposed that the word “epilepsy” should be extended to cover violent rages, somnambulism, and acts of automatic behavior (such as a man undressing himself in the street), construed as episodes of temporary dysfunction in cerebral cortical regions.(Temkin, Owsei, 1971)

Berrios, writing in the Berrios-Porter history of clinical psychiatry, describes this redefinition as embedding epilepsy within an evolutionary and hierarchical model of the nervous system in which seizures were the expression of excessive, abrupt neuronal discharge propagating through hierarchical levels of the brain, a formulation with profound consequences for how the evolution of any individual seizure could be interpreted and its origin localized.(German E. Berrios & Roy Porter (eds.), 1995)

Jackson also challenged the received view that idiopathic epilepsy was an inherited constitutional condition of the nervous system.(Temkin, Owsei, 1971) He proposed instead that the nerve cells suffered secondarily to arterial disease, and that “there is thrombosis or embolism of small arteries in most cases of epilepsy proper,” a vascular hypothesis that implicitly denied genuine epilepsy the status of a Galenic idiopathic disease.(Temkin, Owsei, 1971)

The Evolutionary-Hierarchical Model

Jackson’s account of nervous system organization drew directly on Herbert Spencer’s evolutionary philosophy. In Spencer’s framework, biological development moved from the homogeneous to the heterogeneous, from the simple to the complex, and from the automatic to the voluntary. Jackson transposed this scheme into neuroanatomy, describing three hierarchical levels of the central nervous system: the lowest, comprising the spinal cord, medulla oblongata, and pons, controlling simple movements; the middle, centered on the Rolandic motor cortex, representing movements of greater complexity; and the highest, located in the prefrontal regions, responsible for the most elaborately learned and voluntary acts.(Temkin, Owsei, 1971)

“Dissolution” was the term Jackson coined for the reverse process: what happened during disease. When the highest centers were disrupted by a discharging lesion, two things occurred simultaneously: the functions they normally exercised were lost, and the lower centers, previously held under inhibitory control, were released from that control and became active on their own account. This is the distinction between negative symptoms (loss of function) and positive symptoms (the released activity of subordinate centers). Canguilhem, in his discussion of Jackson’s contribution in The Normal and the Pathological, captures the principle precisely: “A lesion in the higher nervous system frees the lower regulatory and control centers. Lesions are responsible for the loss of certain functions, but the disturbances of existing functions must be attributed to the appropriate activity of henceforth insubordinate centers.”(Canguilhem, 1966)

Canguilhem read this as a general model for pathological thinking: no disease of the nervous system could have a purely negative cause. Every deficit was accompanied by a positive re-organization at a lower level. This principle proved generative well beyond epilepsy. Canguilhem also notes that Jackson’s dissolution model directly influenced Kurt Goldstein’s clinical work on neurological injury, which in turn shaped a broader phenomenological tradition in medicine.(Canguilhem, 1966)

Jackson was equally careful about the limits of what his physiological model could say. He maintained a strict psychophysical parallelism: mind and brain events were parallel processes that ran alongside each other without causal interaction. “There is no physiology of the mind any more than there is psychology of the nervous system,” he wrote, and a physician’s aim should be to deal with diseases of the mind “as materialistically as possible.” This position, as Temkin shows, made his approach fundamentally irreconcilable with the psychological reading of hysteria being developed by Charcot and, later, Freud.(Temkin, Owsei, 1971) Fear could cause an epileptic fit, but not through its psychological content; only through the general bodily change concomitant with strong emotion.

Makari describes how Freud, in his 1891 work on aphasia, cited Jackson’s psychophysical parallelism as a pragmatic research strategy: treating mind and brain as parallel systems that did not causally affect each other could simplify neurological investigation. But as Makari notes, this approach “proved useless to Freud” once he turned to the study of hysteria, where sealing off the mind from the body was precisely the wrong move.(Makari, George, 2008)

The Jacksonian March and Cortical Localization

Jackson’s analysis of unilateral convulsions established that the order in which body parts were drawn into a seizure was not random.(Temkin, Owsei, 1971) Most frequently convulsions began in the hand, and within the hand they started in the thumb and forefinger.(Temkin, Owsei, 1971) Jackson argued that this sequence reflected “the order of intelligence” of the muscles involved: those employed in the most elaborate and learned movements were most largely represented in the corpus striatum and optic thalamus and were therefore first to discharge when those centers became pathologically unstable.(Temkin, Owsei, 1971)

Jackson’s clinical deduction that localized muscle groups could be irritated from small cortical regions was experimentally proven by Fritsch and Hitzig in 1870.(Temkin, Owsei, 1971) Their experiments demonstrated that weak currents applied to small cortical regions could excite localized groups of muscles, and that prolonged stimulation produced convulsions that developed into well characterized epileptic attacks.(Temkin, Owsei, 1971) This experimental validation arrived simultaneously with Jackson’s Study on Convulsions.(Temkin, Owsei, 1971)

The forerunners of this clinical observation stretch back to Bravais in 1827, who described five varieties of hemiplegic epilepsy and documented the march of convulsions from arm to face to trunk, and to Bright at Guy’s Hospital, who observed preserved consciousness during localized seizures and inferred that “epilepsy generally depends upon irritation on the surface of the brain.”(Temkin, Owsei, 1971)(Temkin, Owsei, 1971)

After the surgical demonstrations of the 1880s, Jackson’s principles received their most public vindication. On 13 August 1886, Victor Horsley addressed the British Medical Association on advances in central nervous system surgery and demonstrated three patients on whom successful operations for focal epilepsy had been performed. Both Charcot and Jackson were present, and each congratulated Horsley on his results.(Temkin, Owsei, 1971) The bedside framework built on clinical observation and anatomical inference had generated a surgical discipline.

The recognition of Jacksonian epilepsy as a distinct type associated with gross organic cortical disease was, however, a double-edged outcome.(Temkin, Owsei, 1971) It separated these focal seizures conceptually from idiopathic epilepsy proper, which continued to lack a demonstrable anatomical basis.(Temkin, Owsei, 1971) Hippocampal sclerosis had been reported by Bouchet and Cazauvieilh in 1825, by Meynert in 1867, and by Sommer in 1880, but the leading authorities of the early 1880s remained unwilling to accept these findings.(Temkin, Owsei, 1971) The anatomical basis of what Gowers in 1881 called “a disease of tissue, not of structure” remained unresolved.(Temkin, Owsei, 1971)(Temkin, Owsei, 1971)

Jackson and Migraine

Oliver Sacks, writing in Migraine, reads Jackson’s work as one of the organizing frameworks for understanding the migraine spectrum. The most direct application concerns the distinction between migraine paraesthesiae and the Jacksonian march. Sacks notes that migraine paraesthesiae differ from epileptic ones in two key respects: their centripetal spread takes twenty to thirty minutes rather than seconds, making them roughly a hundred times slower than the corresponding epileptic phenomenon; and they are bilateral in more than half of all cases, whereas epileptic auras start unilaterally in the vast majority.(Sacks, Oliver, 1970/1992) The comparison is made possible only by Jackson’s prior delineation of the epileptic march as a systematic clinical category.

Jackson himself addressed the relationship between migraine and epilepsy in terms that Sacks repeatedly cites. The resolution of the nosological question, Jackson argued, depended on maintaining the distinction between scientific and practical classification: “While scientifically migraine is, I think, to be classified with epilepsies … it would be as absurd to classify it along with ordinary cases of epilepsy as to class whales with other mammals for purposes of practical life. A whale is in law a fish; in zoology it is a mammal.”(Sacks, Oliver, 1970/1992) This position was consistent with the dual classification system Jackson had developed for epilepsy itself: a scientific frame (all epilepsies as grey matter discharges) and an empirical clinical frame (grand mal, petit mal, epileptic vertigo as practical categories).(Temkin, Owsei, 1971)

Jackson’s phrase “mental diplopia” appears in Sacks’s account of dreamy states and disturbances of consciousness. In the dreamy state that could accompany epileptic or migrainous aura, Jackson described a doubling of consciousness: “(1) the quasi-parasitical state of consciousness (dreamy state), and (2) there are remains of normal consciousness and thus, there is double consciousness … a mental diplopia.”(Sacks, Oliver, 1970/1992) Sacks extends this to argue that understanding migraine as a psychophysiological event requires maintaining just such a double language, one for the physical and one for the emotional, simultaneously.(Sacks, Oliver, 1970/1992)

In Chapter 11 of Migraine, Sacks adopts Jackson’s hierarchical model to explain the variability of the migraine syndrome.(Sacks, Oliver, 1970/1992) The same physiological sequence, Sacks proposes, can be expressed at the highest Jacksonian level (complex aura), the middle (elementary aura), or the lowest level (common migraine or equivalent), with collateral spread allowing wide format variation.(Sacks, Oliver, 1970/1992)

Reception and Influence

Temkin’s assessment is measured and historical. Jackson’s significance, he argues, lay not in priority of discovery (the clinical phenomena he described had forerunners in Bravais, Bright, Todd, and Wilks) but in the mode of investigation: an analytical method that correlated clinical observation with anatomical and physiological principles and produced results more enduring than those of contemporaries who dominated the field in their own time.(Temkin, Owsei, 1971) Gowers, writing in 1881, attributed to Jackson the inauguration of “a new era in the study of epilepsy,” but Temkin suggests the phrase understates the matter by locating Jackson’s contribution in the observation of seizure onset and aura. The contribution was the entire mode of reasoning.

In The Normal and the Pathological, Jackson represents nervous system disease as dissolutions of hierarchical functions, where every disease corresponds to a level in the hierarchy and the negative as well as the positive aspect must be considered.(Canguilhem, 1966) In A Vital Rationalist, Sherrington’s concept of neural integration synthesized reflex action with the organism’s holistic behavior, resolving the historical tension between mechanical, vitalist, and teleological explanations of involuntary movement.(Canguilhem, 1994)

Sacks’s reception was more personal and more expansive. He adopted Jackson’s hierarchical model, his dual-frame method, his phrase “mental diplopia,” and his way of treating the paroxysmal nervous system as a family of related conditions graded across a continuum. In his historical introduction to Migraine, Sacks describes Jackson as part of the tradition that included Liveing’s theory of “nerve storms,” the lineage of Victorian neurologists who understood migraine and epilepsy as belonging together in a broader category of paroxysmal reactions.(Sacks, Oliver, 1970/1992) For Sacks, every patient with classical migraine “opened out … into an entire encyclopaedia of neurology,“(Sacks, Oliver, 1970/1992) and it was Jackson’s system of levels that made the encyclopaedia intelligible rather than simply overwhelming.

In British psychiatry, Daniel Hack Tuke introduced the term “imperative ideas” for obsessional phenomena, while he and Hughlings Jackson exchanged views on their neurological basis.(German E. Berrios & Roy Porter (eds.), 1995)

The surgical lineage runs from Jackson’s principles to Horsley in 1886, and from Horsley to modern epilepsy surgery. Temkin frames this vindication concisely: the principles of cortical localization and the discharging lesion, derived from clinical observation and post-mortem inference over two decades, generated within a generation a new surgical discipline.(Temkin, Owsei, 1971)

Wider Significance

Temkin identifies a structural parallel between seventeenth-century iatrochemists and late nineteenth-century neurologists: both assumed the epileptic attack was a necessary consequence of pathological changes in the central nervous system, bare of biological purpose or psychological meaning.(Temkin, Owsei, 1971) Jackson’s doctrine thus repeated the mechanist tradition at a higher level of biological sophistication.(Temkin, Owsei, 1971)

The strict psychophysical parallelism that followed from this mechanist commitment had both productive and limiting consequences. It was productive because it focused attention on the physiology of the nervous system and ruled out premature appeals to the psychological content of symptoms. It was limiting because it made Jackson’s system unable to address the psychological dimensions of neurological phenomena that Charcot, and then Freud, were beginning to investigate. The separation of neurological and psychiatric traditions in the late nineteenth century, the rigid partition of “nervous disorders” into organic and functional that Sacks describes as a fracture occurring at the start of the nineteenth century,(Sacks, Oliver, 1970/1992) was both reflected in and reinforced by Jackson’s insistence that the physician should treat diseases of the mind “as materialistically as possible.”(Temkin, Owsei, 1971)

Scholarly Assessment

Temkin’s The Falling Sickness provides the most detailed account of Jackson’s place in the history of epilepsy. Its key claims are: that Jackson’s forerunners had described the essential clinical phenomena; that what Jackson provided was an analytical method, not a new set of discoveries; that this method proved more enduring than that of contemporaries (including Charcot) who dominated their fields in the short term; and that the subsequent surgical vindication confirmed the clinical deductions in a manner that Jackson did not live to organize into a systematic response.(Temkin, Owsei, 1971)(Temkin, Owsei, 1971)

Berrios and Porter situate Jackson within the history of clinical psychiatry as the figure who restructured epilepsy’s conceptual framework from the inside, embedding it in a general theory of the nervous system that had implications for every paroxysmal condition.(German E. Berrios & Roy Porter (eds.), 1995) This general frame is what distinguished Jackson from predecessors like Wilks, who had proposed cortical primacy without the evolutionary hierarchy, and from contemporaries like Gowers, who accepted the discharge definition while retaining practical categories that Jackson regarded as scientifically arbitrary.

Canguilhem reads Jackson as a philosophical ally in the critique of purely quantitative theories of pathology. The dissolution model shows that disease of the nervous system produces genuinely positive (if lower-level) reorganizations, not merely deficits. This point is used by Canguilhem to argue against the view that pathology differs from physiology only in degree, never in kind.(Canguilhem, 1966)

Porter’s The Greatest Benefit to Mankind places Jackson in the wider history of neurology alongside Ramon y Cajal, Sherrington, and Ferrier, as one of the figures who between roughly 1860 and 1910 established the scientific basis for understanding the brain as a functionally organized system.(Temkin, Owsei, 1971) Porter does not analyze Jackson’s ideas in depth; his significance is acknowledged at the level of persons mentioned rather than arguments developed.

Sacks adopts Hughlings Jackson’s hierarchical model of nervous organization to explain migraine variability, noting that the same migraine sequence may be expressed at the highest Jacksonian level (complex aura), middle (elementary aura), or lowest level (common migraine or equivalent), with collateral spread allowing wide format variation.(Sacks, Oliver, 1970/1992)

Human Notes

Nothing recorded yet.