Flechsig, Paul Emil

(b. Zwickau, Germany, 29 June 1847; d. Leipzig, Germany, 22 July 1929)

neuroanatomy, psychiatry, neurology.

His father, Emil Flechsig, a cultured man and a good friend of Robert Schumann, was a deacon of the Protestant church of St. Mary in Zwickau and much concerned with local social welfare. His monther, Ferdinande Richter, came from a wealthy family. Flechsig was educated in Zwickau, mainly at the Gymnasium, and at the medical school of the University of Leipzig from the spring of 1865 until June 1870, where he was taught in anatomy by E. H. Weber and E. F. W. Weber and in physiology by Karl Ludwig. Ludwig was especially impressed by Flechsig’s histological work, and he encouraged and advised him in it.

Flechsig spent two years (1870–1871) in the army during the Franco-Prussian War and on 1 January 1872 became assistant to Ernst Wagner of the Institute of Pathology in the University of Leipzig. He also worked in the medical polyclinic. He was further able to develop his skills in histology and on 1 October 1873 was appointed head of the department of histology in the Institute of Physiology. Here he devoted all his time to research and benefited greatly from the facilities available and the contact with many outstanding German and foreign physiologists. By 1875 he was university lecturer and in 1877 became professor extraordinarius in the new chair of psychiatry; he soon was made ordinarius. After studying psychiatry at various European centers, on 2 May 1882 he returned to open the clinic of which he was director. Here he spent the rest of his working life and attracted many pupils and visitors, including Beevor, Bekhterev, Blumenau, Darkshevich, Donaldson, Held, Klimor, Martinotti, R. A. Pfeifer, Popov, Schütz, Tschirch, Oskar Vogt, and Yakovenko.

From 1894 to 1895 Flechsig was rector of the University of Leipzig and in 1901, along with the elder Wilhelm His, he helped to found the International Brain Commission, which planned to unify nomenclature, standardize methods, collect material, and encourage research in neuroanatomy. He was made an honorary member of the University of Dorpat in 1903, received the honorary D.Sc. of Oxford in 1904, and became honorary doctor of his alma mater in 1909. At the age of seventy-four he retired but continued working.

Flechsig was a true Vogtländer, with a thick neck, a large barrel-shaped trunk, and short legs. He wore a broad-brimmed hat and a velvet cloak with large glass buttons, resembling therefore, it was said by some, his psychiatric patients.

Flechsig had a cyclothymic personality, almost bordering on a true manic-depressive state. Years of intense activity—when he worked ceaselessly and poured out ideas, encouragement, and inspiration—alternated with years when he was irritable, arrogant, intolerant, tyrannical, and suffered from severe depression. Nevertheless his students and followers venerated him, and Pfeifer records that “his guidance was full of spirit and during discussions of various problems his whole youth was awakened.” He was devoted to his work and had little time for anything else until late in life. He liked to mix with aristocrats, monarchs, and politicians, in part because of their interest in his work and in part because of his need for extramural research funds.

Flechsig married Auguste Hauff in 1870. After her death, in 1922 he married Irene Colditz, who was thirty years younger than he; she was able to interest him in social events during the closing years of his life.

Although Flechsig contributed to the clinical and pathological study of hysteria, epilepsy, neurosyphilis, and chorea, his fame is due mainly to his technique of myelogenesis for the examination of the brain and spinal cord. As Wagner’s assistant, he was impressed by the work of Meynert on the brain and in 1872 began to investigate the myelination in the spinal cord and brain of premature, full-term, and early postnatal infants. He discovered that axones in different parts receive their myelin sheath at different stages of growth, and he could observe the chronological sequence of this process. He was therefore able to differentiate some of the innumerable pathways and concluded correctly that a tract functions adequately only when its axones become fully myelinated. His technique was thus the reverse of Ludwig Türk’s and of those of other workers who used the process of secondary or Wallerian degeneration to trace tracts.

Flechsig first examined the spinal cord and, like Türck and others, identified several pathways. He reported this work in 1876 (Leitungsbahnen im Gehirn and Rückenmark . . .) and related it to that of Türck; a description of what is now called Flechsig’s tract, the dorsal spinocerebellar, is included.

His monumental work on the pyramidal tract—in which for the first time he traced its origin to the cerebral cortex—appeared in parts in 1877 and 1878. It is the first clear account of the upper motor neurone, and the now familiar division of the internal capsule into knee and limbs is his.

In 1893 Flechsig began more intensive study of the cerebral hemispheres and supplemented his myelogenetic findings with clinical observations and data from degeneration experiments. He outlined the auditory radiation and could list twelve cortical areas that are myelinated (and therefore functional) before birth, as well as twenty-four in which myelinization occurs after birth; these he arranged chronologically according to the time of myelinization. He thus isolated primarily projection, or motor and sensory, areas, the fiber connections of which, both corticopetal and corticofugal, mostly mature prenatally; and association areas responsible, he claimed, for higher intellectual functions that develop after birth. From this he evolved a map of cortical function that appeared in a report of 1904 to the Central Committee for Brain Research. Flechsig’s conclusions evoked considerable argument, especially from Leonardo Bianchi concerning frontal lobe function and Oskar Vogt on the techniques of myelogenesis. It is now clear that although Flechsig made many errors and ignored the work of others with which his results did not agree, he nevertheless stimulated much beneficial discussion and research.

Flechsig considered the parieto-temporo-occipital association zone to be essential for mental activity (which is at least partially correct), and this is discussed in his rector’s oration of 1896, Gehirn und Seele. The book he published in 1920, Anatomie des menschlichen Gehirn und Rückenmarks . . ., contains most of his data on cortical localization.

BIBLIOGRAPHY

I. Original Works. There is no bibliography or opera omnia of Flechsig, but Pfeifer (1930) has published a list of forty-nine of his most important writings from 1872 to 1920, all but one being on brain anatomy. Among these are Die Leitungsbahnen im Gehirn und Rückenmark des Menschen auf Grund entwicklungsgeschichtlicher Untersuchungen (Leipzig, 1876); “Über ‘Systemerkrankungen’ im Rückenmark,” in Archiv für der Heilkunde, 18 (1877), 101–141, 289–343, 461–483, and ibid, 19 (1878), 52–90, 441–447; “Zur anatomie und Entwicklungsgeschichte der Leitungsbahnen im Grosshirn des Menschen,” in Archiv fur Anatomie und physiologie (Anatomische Abteilung) (1881), pp. 12–75; plan des menschlichen Gehirns auf Grund einziger Untersuchungen (Lipzig, 1883); Gehirn und Seele (Leipzig, 1896), his rectorial oration, with extensive notes; “Einige Bemerkungen über die Untersuchungs-methoden der Grosshirnrinde,’ insbesondere des Menschen. Dem Zentralkomitee fur Hirnforschung vorgelegt von . . .,” in Berichie über die Verhandlungen der Sächsischen Akademie der Wissenschaften zu Leipzig, Math-Phys. Klasse, 56 (1904), 50–104 (with 4 plates), 177–248; and Anatomic des menschlichen Gehirns und Rückenmarks auf myelogenetischer Grundlage, vol. I (Leipzig, 1920).

Useful English and French accounts of Flechsig’s technique as applied to the cerebral cortex are “Developmental (Myelogenetic) Localisation of the Cerebral Cortex in the Human Subject,” in Lancet (1901), 2 , 1027–1029; and “Les centres de projection et d’association du cerveau humain,” in Proceedings. XIII^e Congrès International de Médecine (Section de Neurologie) (Paris, 1900), pp. 115–121. E. Clarke and C.D.O’Malley, The Human Brain and Spinal Cord (Berkeley-Los Angeles, 1968), contains English translations of some of Flechsig’s writings: on spinal cord tracts, pp. 277–280, 287–290; on cerebral cortical localization, pp. 548–554; on cerebral white matter, pp. 611–619; and on the technique of myelogenesis, pp. 857–858; each contribution is discussed in relation to other work on the same subject.

II. Secondary Literature. There is no biography of Flechsig, and the various brief accounts of his life are based on his autobiography, Meine myelogenetische Hirnlehre mit biographischer Einleitung (Berlin, 1927): some of these are W. Haymaker, “Paul Emil Flechsig (1847–1929).” in his ed. of The Founders of Neurology (Springfield, Ill., 1953), pp. 31–35 (with a portrait); Henneberg, “Paul Flechsig †,” in Medizinische Klinik, 25 (1929), 1490–1492; R. A. Pfeifer, “Paul Flechsig †. Sein Leben und sein Wirken,” in Shweizer Archio für Neurologic und Psychiairie,26 (1930), 258–264; F. Quensel, “Paul Flechsig zum 70. Geburtstag,” in Deutsche medizinische Wochenscrift, 43 (1917), 818–819; and P, Schroder,”Paul Flechsig,” in Archiv für Psychiatrie and Nervenkrankheiten, 91 (1930).1–8.

Concerning Flechsig’s work, see L. F. Barker, “The Phrenology of Gall and Flechsig’s Doctrine of Association Centers in the Cerebrum,” in Bulletin of the Johns Hopkins Hospital, 8 (1897), 7–14; and “The Sense-areas and Association-centers in the Brain as Described by Flechsig,” in Journal of Nervuos and Mental Diseases, 24 (1897), 325–356, 363–368 (discussion); W. W. Ireland, “Flechsig on the Localization of Mental Processes in the Brain,” in Journal of Mental Science, 44 (1898), 1–17; M. P. Jacobi, “Considerations on Flechsig’s ‘Gehirn und Seele,’” in Journal of Nervous and Mental Diseases, 24 (1897), 747–768;J.M. Nielsen, “The Myelogenetic Studies of Paul Flechsig,” in Bulletin of the Los Angeles Neurological Society, 28 (1963), 127–134; and F. R. Sabin, “On Flechsig’s Investigations on the Brain,” in Bulletin of the Johns Hopkins Hospital,16 (1905), 45–49.

Flechsig’s Festschrift, in Monatsschrift fur Psychiatric und Neurologie,26 (1909), 1–416, with 19 plates, has an excellent photograph of him in his laboratory, but no biography or bibliography.

Edwin Clarke