Arnold, Friedrich

ARNOLD, Friedrich (1803–1890), studied anatomy at the University of Heidelberg under the guidance of Tiedemann and Fohmann. In 1825, he defended his dissertation 'Dissertatio inauguralis sistens observationes nonnullas neurologicas de parte cephalica nervi sympathici in homine' (A dissertation containing some neurological observations on the cephalic part of the sympathetic nerve in man). A year later, after a trip to Paris, Arnold received a prosectorship in anatomy in Heidelberg and published a number of outstanding works on the anatomy of the sympathetic nerve, the otic ganglion, and the organ of vision. In 1834, already an extraordinary professor, he published the famous 'Icones nervorum capitis'. A year later, Arnold became an ordinary professor and director of the Anatomical Institute in Zurich. The most significant works of this period are: 'Annotationes anatomicae de velamentis cerebri et medullae spinalis', 'Bemerkungen über den Bau des Hirns und Rückenmarks', 'Tabulae anatomicae ad naturam accuratae descriptae'. All of them are provided with artistically executed drawings from his own preparations. In 1840, Arnold moved to Freiburg and published 'Handbuch der Anatomie des Menschen', then moved to Tübingen, and finally, in 1852, returned to Heidelberg, where, as a distinguished professor of anatomy and physiology, he ended his many years of brilliant research, teaching, and literary activity, working by then mainly in the field of physiology.

ARNOLD FIBERS, BUNDLE, GANGLIA (Arnold). Arnold fibers belong to the shortest association fibers and connect two adjacent gyri, occupying a superficial position in their white

matter. Arnold bundle (fasciculus temporo-thalamicus) connects the pulvinar and the corpus geniculatum laterale with the cortex of the occipital and temporal lobes; it has a very tortuous path under the bundle of Türk. Arnold ganglia, nerve ganglia described by Arnold, relating to the autonomic nervous system (see): 1) gangl. oticum, in which fibers from the nucl. salivatorius inferior terminate and from which fibers emerge for the innervation of the parotid gland; 2) gangl. cardiacum medium, related to the n. cardiacus medius; and 3) gangl. splanchnicum, adjacent to the n. splanchnicus major.