Paul Flechsig

Paul Emil Flechsig (June 29, 1847 - July 22, 1929) was a German neuroanatomist, psychiatrist and neuropathologist. Born in Zwickau, he spent over fifty years of his medical career at the University of Leipzig. Although Flechsig contributed much in regards to his study of neurological disorders, he is mainly remembered today concerning his research regarding myelinogenesis. Among his students were Emil Kraepelin and Oskar Vogt (mentor to Korbinian Brodmann). Flechsig was the treating psychiatrist for Daniel Paul Schreber, whose memoir inspired Sigmund Freud to publish a detailed analysis of the case in 1911. Flechsig's work has still not been rediscovered widely but his map was reprinted and discussed in Fuster's "Cortex and Mind".

Myelinogenesis is a technique he pioneered in which he studied brains of the late term fetus and newborn by staining for myelin. Between about two months before and after birth, most of the cerebral cortex becomes myelinated. The order in which this happens appears to reflect the evolutionary order of mammals from less to more complex. He derived a map of the cerebral cortex divided not by histology (as Korbinian Brodmann did) but by order of myelination.

Flechsig divided the cortical regions into:
# an early myelinating primitive zone, which includes the motor cortex and the visual, auditory, and somatosensory cortex;
# a field bordering the primitive zone that myelinates next;
# a late-myelinating zone, which he called “association”. [Kolb & Whishaw: "Fundamentals of Human Neuropsychology," 2003] The last area of the human cerebral cortex to myelinate is the Dorsolateral Prefrontal cortex. (Flechsig #45, Brodmann areas 9 & 46). This region continues to develop in adolescence and adulthood it is related to executive function and working memory.

The "Paul-Flechsig-Institute of Brain Research" at the University of Leipzig is an institution established in 1974 in tribute to Flechsig. The institute's scientific emphases is on cellular and molecular aspects of neurodegenerative diseases and glial reactions in the brain and the retina.

Flechsig's fasciculus or Flechsig's tract is a neurological structure which conveys proprioceptive information from the body to the cerebellum.

Bibliography

* Die Leitungsbahnen im Gehirn und Rückenmark des Menschen auf Grund entwicklungsgeschichtlicher Untersuchungen (1876)
* [http://vlp.mpiwg-berlin.mpg.de/references?id=lit16508 Ueber Darstellung und chemische Natur des Cellulosezuckers] . Zeitschrift für Physiologische Chemie 7: 523-540 (1882-83)
* Ueber eine neue Färbungsmethode des centralen Nervensystems und deren Ergebnisse bezüglich des Zusammenhanges von Ganglienzellen und Nervenfasern. Archiv für Physiologie: 537-538 (1889)
* Gehirn und Seele (1896)
* Die Localisation der geistigen Vorgänge insbesondere der Sinnesempfindungen des Menschen: Vortrag gehalten auf der 68. (1896)
* Anatomie des menschlichen Gehirns und Rückenmarks auf myelogenetischer Grundlage (1920)
* Die myelogenetische Gliederung der Leitungsbahnen des Linsenkerns beim Menschen. Berichte über die Verhandlungen der Königlich Sächsischen Gesellschaft der Wissenschaften zu Leipzig: Mathematisch-Physische Klasse 73: 295-302 (1921)

References

*J.M. Fuster - Cortex and Mind: Unifying Cognition, Oxford University Press, 2003.

External links

* [http://vlp.mpiwg-berlin.mpg.de/people/data?id=per336 Picture, biography and bibliography] in the Virtual Laboratory of the Max Planck Institute for the History of Science
* [http://www.uni-leipzig.de/~pfi/ Official site of the Paul-Flechsig-Institute of Brain Research] in Leipzig (mainly German, some English)